zint/docs/manual.txt

*******************************************************************************
* For reference the following is a text-only version of the Zint manual.      *
* The full version can be accessed at http://zint.org.uk/Manual.aspx          *
*******************************************************************************

Zint Barcode Generator and Zint Barcode Studio User Manual
==========================================================

1. Introduction
===============
The Zint project aims to provide a complete cross-platform open source barcode
generating solution. The package currently consists of a Qt based GUI, a 
command line executable and a library with an API to allow developers access to 
the capabilities of Zint. It is hoped that Zint provides a solution which is 
flexible enough for professional users while at the same time takes care of as 
much of the processing as possible to allow easy translation from input data to 
barcode image. 

The library which forms the main component of the Zint project is currently 
able to encode data in over 50 barcode symbologies (types of barcode), for each 
of which it is possible to translate that data from either Unicode (UTF-8) or a 
raw 8-bit data stream. The image can be rendered as either a Portable Network 
Graphic (PNG) image, Windows Bitmap (BMP), Graphics Interchange Format (GIF), 
ZSoft Paintbrush image (PCX), as Encapsulated Post Script (EPS) or as a 
Scalable Vector Graphic (SVG). Many options are available for setting the 
characteristics of the output image including the size and colour of the image, 
the amount of error correction used in the symbol and, in the case of raster 
images, the orientation of the image. 

1.1 Terms of Reference
----------------------
Some of the words and phrases used in this document are specific to barcoding,
and so a brief explanation is given to help understanding:

symbol: A symbol is an image which encodes data according to one of the
        standards. This encompases barcodes (linear symbols) as well as any of
        the other methods of representing data used in this program.
        
symbology: A method of encoding data to create a certain type of symbol.

linear: A linear symbol is one which consists of bars and spaces, and is what
        most people associate with the term "barcode". Examples include EAN.
        
stacked: A stacked symbol consists of multiple linear symbols placed one above
        another and which together hold the message, usually allong side some
        error correction data. Examples include PDF417.
        
matrix: A matrix symbol is one based on a (usually square) grid of elements.
        Examples include Data Matrix, but Maxicode and DotCode are also
        considered matrix symbologies.
        
x-dimension: The x-dimension of a symbol is size (usually the width) of the
        smallest element. For a linear symbology this is the width of the
        smallest bar. The default size of the x-dimension in a raster image
        is 2 pixels. Many symbologies have a fixed width-to-height ratio where
        the height is expressed as a multiple of the x-dimension.
        
composite: A composite symbology is one which is made up of elements which are
        both linear and stacked. Those currently supported are made up of a
        linear "primary" message above which is printed a stacked component
        based on the PDF417 symbology. These symbols also have a separator
        which seperates the linear and the stacked components.
        
GS-1 data: This is a structured way of representing information which consists
        of "chunks" of data, each of which starts with an Application
        Identifier. The AI identifies what type of information is being
        encoded. See Appendix C.
        
Reader Initialisation: Some symbologies allow a special character to be included
        which can be detected by the scanning equipment as signifying that the
        data is used to program or change settings in that equipment. This data
        is usually not passed on to the software which handles normal input
        data. This feature should only be used if you are familiar with the
        programming codes relevant to your scanner.
        
ECI:    The ECI mechanism allows for multi-language data to be encoded in
        symbols which would usually support only Latin-1 characters. This can
        be useful, for example, if you need to encode cyrillic characters, but
        should be used with caution as not all scanners support this method.

2. Installing Zint
==================

2.1 Linux
---------
The easiest way to configure compilation is to take advantage of the CMake 
utilities. You will need to install CMake and libpng first. Note that you will 
need both libpng and libpng-devel packages. If you want to take advantage of 
Zint Barcode Studio you will also need the Qt libraries pre-installed.

Once you have fulfilled these requirements unzip the source code tarball and 
follow these steps in the top directory:

mkdir build
cd build
cmake ..
make
make install

The command line program can be accessed by typing

zint {options} -d {data}

Notice that the data needs to be entered after all other options. Any options 
given after the data will be ignored. The GUI can be accessed by typing

zint-qt

To test that the installation has been successful a shell script is included in 
the /frontend folder. To run the test type

./test.sh

This should create numerous files showing the many modes of operation which are 
available from Zint.

2.2 Microsoft Windows
---------------------
To run Zint Barcode Studio on Windows simply download and run the installation 
executable and follow the instructions on-screen.

2.3 Apple macOS
---------------
Zint can be compiled on macOS from the command line using the same steps as shown 
for Linux above. Currently the Zint Barcode Studio GUI is not known to work on 
macOS. The Zint developers do not currently have access to Apple hardware and
so are not able to provide support or binaries for macOS. If you are a macOS
developer, however, or if you have any success in building Zint on macOS, we
would love to hear from you.


3. Using Zint Barcode Studio
============================
Zint Barcode Studio is the graphical user interface for Zint. If you are
starting from a command line interface you can start the GUI by typing

zint-qt

or in Windows

zint-qt.exe


(The rest of this section of the manual involves use of the GUI, so has been
removed from this text-only version)


4. Using the Command Line
=========================
This section describes how to encode data using the command line front end 
program. The examples given are for the Linux platform, but the same options
are available for Windows - just rememer to include the executable file
extension. i.e.:

zint.exe -d "This Text"


4.1 Inputting data
------------------
The data to encode can be entered at the command line using the -d option, for 
example 

zint -d "This Text"

This will encode the text "This Text". Zint will use the default symbology, 
Code 128, and output to the default file out.png in the current directory. 
Alternatively, if libpng was not present when Zint was built, the default
output file will be out.gif. The -d switch and the input data should always
be the last entry on the command line input. Any options given after this
will be ignored. 

The data input to Zint is assumed to be encoded in Unicode (UTF-8) format. If 
you are encoding characters beyond the 7-bit ASCII set using a scheme other than 
Unicode then you will need to set the appropriate input options as shown in 
section 4.11 below. 

Non-printing characters can be entered on the command line using the backslash 
(\) as an escape character. Permissible characters are shown in the table 
below. Note that this only applies on the command line. 

-------------------------------------------------------------
Escape Character  |  ASCII Equivalent  |  Interpretation
-------------------------------------------------------------
\0                |  0x00              |  Null
\E                |  0x04              |  End of Transmission
\a                |  0x07              |  Bell
\b                |  0x08              |  Backspace
\t                |  0x09              |  Horizontal Tab
\n                |  0x0A              |  Line Feed
\v                |  0x0B              |  Vertical Tab
\f                |  0x0C              |  Form Feed
\r                |  0x0D              |  Carriage Return
\e                |  0x1B              |  Escape
\G                |  0x1D              |  Group Selector
\R                |  0x1E              |  Record Selector
-------------------------------------------------------------

Input data can be read directly from file using the -i switch as shown below. 
The input file is assumed to be Unicode (UTF-8) formatted unless an alternative 
mode is selected. This command replaces the use of the -d switch and should
similarly be the last option given.

zint -i ./somefile.txt

4.2 Directing Output
--------------------
Output can be directed to a file other than the default using the -o switch. 
For example:

zint -o here.png -d "This Text"

This draws a Code 128 barcode in the file here.png. If an encapsulated Post Script 
file is needed simply append the file name with .eps, and so on for the other
supported file types:

zint -o there.eps -d "This Text"

4.3 Selecting barcode type
--------------------------
Selecting which type of barcode you wish to produce (i.e. which symbology to 
use) can be done at the command line using the -b or --barcode= switch followed 
by the appropriate integer value in the following table. For example to create
a Data Matrix symbol you could use:

zint -o datamatrix.png -b 71 -d "Data to encode"

--------------------------------------------------------------------------------
Numeric Value  |  Barcode Name
--------------------------------------------------------------------------------
1              |  Code 11
2              |  Standard Code 2 of 5
3              |  Interleaved 2 of 5
4              |  Code 2 of 5 IATA
6              |  Code 2 of 5 Data Logic
7              |  Code 2 of 5 Industrial
8              |  Code 3 of 9 (Code 39)
9              |  Extended Code 3 of 9 (Code 39+)
13             |  EAN (Including EAN-8 and EAN-13)
14             |  EAN + Check Digit
16             |  GS1-128 (UCC.EAN-128)
18             |  Codabar
20             |  Code 128 (automatic subset switching)
21             |  Deutshe Post Leitcode
22             |  Deutshe Post Identcode
23             |  Code 16K
24             |  Code 49
25             |  Code 93
28             |  Flattermarken
29             |  GS1 DataBar-14
30             |  GS1 DataBar Limited
31             |  GS1 DataBar Extended
32             |  Telepen Alpha
34             |  UPC A
35             |  UPC A + Check Digit
37             |  UPC E
38             |  UPC E + Check Digit
40             |  PostNet
47             |  MSI Plessey
49             |  FIM
50             |  LOGMARS
51             |  Pharmacode One-Track
52             |  PZN
53             |  Pharmacode Two-Track
55             |  PDF417
56             |  PDF417 Truncated
57             |  Maxicode
58             |  QR Code
60             |  Code 128 (Subset B)
63             |  Australia Post Standard Customer
66             |  Australia Post Reply Paid
67             |  Australia Post Routing
68             |  Australia Post Redirection
69             |  ISBN (EAN-13 with verification stage)
70             |  Royal Mail 4 State (RM4SCC)
71             |  Data Matrix (ECC200)
72             |  EAN-14
74             |  Codablock-F
75             |  NVE-18
76             |  Japanese Postal Code
77             |  Korea Post
79             |  GS1 DataBar-14 Stacked
80             |  GS1 DataBar-14 Stacked Omnidirectional
81             |  GS1 DataBar Expanded Stacked
82             |  PLANET
84             |  MicroPDF417
85             |  USPS OneCode
86             |  Plessey Code
87             |  Telepen Numeric
89             |  ITF-14
90             |  Dutch Post KIX Code
92             |  Aztec Code
93             |  DAFT Code
97             |  Micro QR Code
98             |  HIBC Code 128
99             |  HIBC Code 39
102            |  HIBC Data Matrix ECC200
104            |  HIBC QR Code
106            |  HIBC PDF417
108            |  HIBC MicroPDF417
112            |  HIBC Aztec Code
115            |  DotCode
116            |  Han Xin (Chinese Sensible) Code
128            |  Aztec Runes
129            |  Code 32
130            |  Composite Symbol with EAN linear component
131            |  Composite Symbol with GS1-128 linear component
132            |  Composite Symbol with GS1 DataBar-14 linear component
133            |  Composite Symbol with GS1 DataBar Limited component
134            |  Composite Symbol with GS1 DataBar Extended component
135            |  Composite Symbol with UPC A linear component
136            |  Composite Symbol with UPC E linear component
137            |  Composite Symbol with GS1 DataBar-14 Stacked component
138            |  Composite Symbol with GS1 DataBar-14 Stacked Omnidirectional 
               |     component
139            |  Composite Symbol with GS1 DataBar Expanded Stacked component
140            |  Channel Code
141            |  Code One
142            |  Grid Matrix
--------------------------------------------------------------------------------

4.4 Adjusting height
--------------------
The height of a linear symbol can be adjusted using the --height switch. For 
example:

zint --height=100 -d "This Text"

This specifies a symbol height of 100 times the x-resolution of the symbol.

4.5 Adjusting whitespace
------------------------
The amount of whitespace to the left and right of the generated barcode can be 
altered using the –w switch. For example:

zint -w 10 -d "This Text"

This specifies a whitespace width of 10 times the x-resolution of the symbol.

4.6 Adding boundary bars and boxes
----------------------------------
Zint allows the symbol to be bound with 'boundary bars' using the option 
--bind. These bars help to prevent misreading of the symbol by corrupting a 
scan if the scanning beam strays off the top or bottom of the symbol. Zint can 
also put a border right around the symbol and its whitespace with the --box 
option. This option is automatically selected for ITF-14 symbols.

The width of the boundary or box can be specified using the --border switch. 
For example:

zint --box --border=10 -d "This"

gives a box with a width 10 times the x-resolution of the symbol.

4.7 Using colour
----------------
The default colours of a symbol are a black symbol on a white background. Zint 
allows you to change this. The -r switch allows the default colours to be 
inverted so that a white symbol is shown on a black background. For example the 
command

zint -r -d "This"

gives an inverted Code 128 symbol. This is not practical for most symbologies 
but white-on-black is allowed by the Data Matrix ECC200 and Aztec Code 
symbology specifications.

For more specific needs the foreground (ink) and background (paper) colours
can be specified using the --fg= and --bg= options followed by a number in RRGGBB
hexadecimal notation (the same system used in HTML). For example the command

zint --fg=004700 -d "This"

alters the symbol to a dark green.

4.8 Rotating the Symbol
-----------------------
The symbol can be rotated through four orientations using the --rotate= option 
followed by the angle of rotation as shown below. This option is only available 
with raster image (PNG, BMP, GIF and PCX) output. 

--rotate=0 (default)
--rotate=90
--rotate=180
--rotate=270

4.9 Adjusting image size
------------------------
The scale of the image can be altered using the --scale= option followed by a 
multiple of the default x-dimension. The default x-dimension is 2 pixels. For
example for PNG images a scale of 5 will increase the x-dimension to 10 pixels. 

4.10 Input modes
----------------
By default all input data is assumed to be encoded in Unicode (UTF-8) format. 
Many barcode symbologies encode data using Latin-1 (ISO-8851-1) character 
encoding, so input is converted from Unicode to Latin-1 before being put in the 
symbol. In addition QR Code, Micro QR Code, Han Xin Code and Grid Matrix 
standards can encode Chinese or Japanese characters which are also converted 
from Unicode. If Zint encounters characters which can not be encoded using the 
default character encoding then it will take advantage of the ECI (Extended 
Channel Interpretations) mechanism to encode the data. Be aware that not all 
barcode readers support ECI mode, so this can sometimes lead to unreadable 
barcodes. If you are using characters beyond those supported by Latin-1 then 
you should check that the resulting barcode can be understood by your target 
barcode reader. Zint will generate a warning message when ECI codes have been
inserted into a symbol.

GS1 data can be encoded in a number of symbologies. Application identifiers
should be enclosed in [square brackets] followed by the data to be encoded (see 
5.1.12.3). To encode GS1 data use the --gs1 option. GS1 mode is assumed (and 
doesn't need to be set) for EAN-128, DataBar and Composite symbologies but is 
also available for Code 16k, Data Matrix, Aztec Code, DotCode and QR Code. 

The --binary option prevents Zint from performing any convertion of the data 
before placing in the barcode symbol and should be used if you are encoding raw 
binary or encrypted data.

If your platform does not use Unicode or if you are using data from file which 
is not stored in UTF-8 then you can specify the encoding by using the --binary 
switch in combination with the --eci= switch followed by the appropriate number 
from the table below. This procedure adds an ECI flag in the barcode data which 
tells the barcode reader to change character encoding.

--------------------------------------------------------
ECI Code  |  Character Encoding Scheme
--------------------------------------------------------
3         |  ISO-8859-1 - Latin alphabet No. 1 (default)
4         |  ISO-8859-2 - Latin alphabet No. 2
5         |  ISO-8859-3 - Latin alphabet No. 3
6         |  ISO-8859-4 - Latin alphabet No. 4
7         |  ISO-8859-5 - Latin/Cyrillic alphabet
8         |  ISO-8859-6 - Latin/Arabic alphabet
9         |  ISO-8859-7 - Latin/Greek alphabet
10        |  ISO-8859-8 - Latin/Hebrew alphabet
11        |  ISO-8859-9 - Latin alphabet No. 5
12        |  ISO-8859-10 - Latin alphabet No. 6
13        |  ISO-8859-11 - Latin/Thai alphabet
15        |  ISO-8859-13 - Latin alphabet No. 7
16        |  ISO-8859-14 - Latin alphabet No. 8 (Celtic)
17        |  ISO-8859-15 - Latin alphabet No. 9
18        |  ISO-8859-16 - Latin alphabet No. 10
21        |  Windows-1250 - Latin 2 (Central Europe)
22        |  Windows-1251 - Cyrillic
23        |  Windows-1252 - Latin 1
24        |  Windows-1256 - Arabic
26        |  Unicode (UTF-8)
--------------------------------------------------------

4.11 Batch processing
---------------------
Data can be batch processed by reading from a text file and producing a 
separate barcode image for each line of text in that file. To do this use the 
--batch switch. To select the input file from which to read data use the –i 
option. Zint will automatically detect the end of a line of text (in either 
Unix or Windows formatted text files) and produce a symbol each time it finds 
this. Input files should end with a return character – if this is not present 
then Zint will not encode the last line of text, and will warn you that there 
is a problem.

By default Zint will output numbered filenames starting with 00001.png, 
00002.png etc. To change this behaviour use the –o option in combination with 
--batch using special characters in the output file name as shown in the table 
below: 

---------------------------------------------
Input Character   |  Interpretation
---------------------------------------------
~                 |  Insert a number or '0'
#                 |  Insert a number or space
@                 |  Insert a number or "*"
Any other         |  Insert literally
---------------------------------------------

The following table shows some examples to clarify this method:

--------------------------------------------------------------
Input            |  Filenames Generated
--------------------------------------------------------------
-o file~~~.svg   |  file001.svg, file002.svg, file003.svg
-o @@@@bar.png   |  ***1.png, ***2.png, ***3.png
-o my~~~bar.eps  |  my001.bar.eps, my002.bar.eps, my003bar.eps
-o t@es~t~.png   |  t*es0t1.png, t*es0t2.png, t*es0t3.png
--------------------------------------------------------------

4.12 Direct output
------------------
The finished image files can be output directly to stdout for use as part of
a pipe by using the --direct option. By default --direct will output data
as a PNG image, but this can be altered by supplimenting the --direct option
with a --filetype= option followed by the suffix of the file type required.
For example:

zint -b 84 --direct --filetype=pcx -d "Data to encode"

This command will output the symbol as a PCX file to stdout. The currently
supported output file formats are shown in the following table:

--------------------------------------------------------------
Abbreviation |  File format
--------------------------------------------------------------
BMP          |  Windows Bitmap
EPS          |  Encapsulated PostScript
GIF          |  Graphics Interchange Format
PCX          |  ZSoft Paintbrush image
PNG          |  Portable Network Graphic
SVG          |  Scalable Vector Graphic
TXT          |  Text file (see 4.16)
--------------------------------------------------------------

=============================================================================
CAUTION: Outputting binary files to the command shell without catching that
data in a pipe can have unpredictable results. Use with care!
=============================================================================

4.13 Automatic filenames
------------------------
The --mirror option instructs Zint to use the data to be encoded as an
indicator of the filename to be used. This is particularly useful if you are
processing batch data. For example the input data "1234567" will result in
a file named 1234567.png.

There are restrictions, however, on what characters can be stored in a file
name, so the file name may vary from the data if the data includes non-
printable characters, for example, and may be shortened if the data input is
long.

To set the output file format use the --filetype= option as detailed in
section 4.12.

4.14 Working with dots
----------------------
Matrix codes can be rendered as a series of dots or circles rather than the
normal squares by using the --dotty option. This option is only available for
matrix symbologies, and is automatically selected for DotCode. The size of
the dots can be adjusted using the --dotsize= option followed by the radius
of the dot, where that radius is given as a multiple of the x-dimension.

4.15 Help options
-----------------
There are three help options which give information about how to use the
command line. The -h or --help option will display a list of all of the valid
options available, and also gives the exact version of the software.

The -t or --types option gives the table of symbologies along with the symbol
ID numbers.

The -e or --ecinos option gives a list of the ECI codes supported by Zint.

4.16 Other output options
-------------------------
For linear barcodes the text present in the output image can be removed by 
using the --notext option.

The text can be set to bold using the --bold option, or a smaller font
can be substituted using the --small option. The --bold and --small options
can be used together if required.

Zint can output a representation of the symbol data as a set of hexadecimal
values if asked to output to a text file (*.txt) or if given the option
--filetype=txt. This can be used for test and diagnostic purposes.

The --cmyk option is specific to output in encapsulated PostScript, and
converts the RGB colours used to the CMYK colour space. Setting custom
colours at the command line will still need to be done in RRGGBB format.

Additional options are available which are specific to certain symbologies. 
These may, for example, control the amount of error correction data or the 
size of the symbol. These options are discussed in section 6 of this guide. 

5. Using the API
================
Zint has been written using the C language and currently only has an API for 
use with C language programs. A wrapper is available for Pascal/Delphi 
developers thanks to theunknownones from 
http://theunknownones.googlecode.com/svn/trunk/Components/ZintBarcode/.
This wrapper, however, is likely to be out of date and may not function as
expected.

The libzint API has been designed to be very similar to that used by the GNU 
Barcode package. This allows easy migration from GNU Barcode to Zint. Zint, 
however, uses none of the same function names or option names as GNU Barcode. 
This allows you to use both packages in your application without conflict if 
you wish. 

5.1 Creating and Deleting Symbols
---------------------------------
The symbols manipulated by Zint are held in a zint_symbol structure defined in 
zint.h. These symbols are created with the ZBarcode_Create() function and 
deleted using the ZBarcode_Delete() function. For example the following code 
creates and then deletes a symbol:

#include <stdio.h>
#include <zint.h>
int main()
{
    struct zint_symbol *my_symbol;my_symbol = ZBarcode_Create();
    if(my_symbol != NULL)
    {
        printf("Symbol successfully created!\n");
    }
    ZBarcode_Delete(my_symbol);
    return 0;
}

When compiling this code it will need to be linked with the libzint library 
using the -lzint option:

gcc -o simple simple.c –lzint

5.2 Encoding and Saving to File
-------------------------------
To encode data in a barcode use the ZBarcode_Encode() function. To write the 
symbol to a file use the ZBarcode_Print() function. For example the following 
code takes a string from the command line and outputs a Code 128 symbol in a 
PNG file named out.png (or a GIF file called out.gif if libpng is not present)
in the current working directory:

#include <stdio.h>
#include <zint.h>
int main(int argc, char **argv)
{
    struct zint_symbol *my_symbol;
    my_symbol = ZBarcode_Create();
    ZBarcode_Encode(my_symbol, argv[1], 0);
    ZBarcode_Print(my_symbol, 0);
    ZBarcode_Delete(my_symbol);
    return 0;
}

This can also be done in one stage using the ZBarcode_Encode_and_Print() 
function as shown in the next example:

#include <stdio.h>
#include <zint.h>
int main(int argc, char **argv)
{
    struct zint_symbol *my_symbol;
    my_symbol = ZBarcode_Create();
    ZBarcode_Encode_and_Print(my_symbol, argv[1], 0, 0);
    ZBarcode_Delete(my_symbol);
    return 0;
}

Input data should be Unicode (UTF-8) formatted.

5.3 Encoding and Printing Functions in Depth
--------------------------------------------
The functions for encoding and printing barcodes are defined as:

int ZBarcode_Encode(struct zint_symbol *symbol, unsigned char *input, int 
length);

int ZBarcode_Encode_File(struct zint_symbol *symbol, char *filename);

int ZBarcode_Print(struct zint_symbol *symbol, int rotate_angle);

int ZBarcode_Encode_and_Print(struct zint_symbol *symbol, unsigned char *input, 
      int length, int rotate_angle);

int ZBarcode_Encode_File_and_Print(struct zint_symbol *symbol, char *filename, 
      int rotate_angle);

In these definitions "length" can be used to set the length of the input 
string. This allows the encoding of NULL (ASCII 0) characters in those 
symbologies which allow this. A value of 0 will disable this function and Zint 
will encode data up to the first NULL character in the input string.

The "rotate_angle" value can be used to rotate the image when outputting as a 
raster image. Valid values are 0, 90, 180 and 270.

The ZBarcode_Encode_File() and ZBarcode_Encode_File_and_Print() functions can 
be used to encode data read directly from a text file where the filename is given
in the "filename" string. 

5.4 Buffering Symbols in Memory
-------------------------------
In addition to saving barcode images to file Zint allows you to access a 
representation of the resulting bitmap image in memory. The following functions 
allow you to do this: 

int ZBarcode_Buffer(struct zint_symbol *symbol, int rotate_angle); 

int ZBarcide_Encode_and_Buffer(struct zint_symbol *symbol, unsigned char 
      *input, int length, int rotate_angle); 

int ZBarcode_Encode_File_and_Buffer(struct zint_symbol *symbol, char *filename, 
      int rotate_angle); 

The arguments here are the same as above. The difference is that instead of 
saving the image to file it is placed in a character array. The "bitmap" 
pointer is set to the first memory location in the array and the values 
"barcode_width" and "barcode_height" indicate the size of the resulting image 
in pixels. Rotation and colour options can be used at the same time as using 
the buffer functions in the same way as when saving to a raster image. The
pixel data can be extracted from the character array by the methd shown in
the example below where render_pixel() is assumed to be a function for drawing
a pixel on the screen implemented by the external application:

int row, col, i = 0;
int red, blue, green;

for (row = 0; row < my_symbol->bitmap_height; row++) {
     for (column = 0; column < my_symbol->bitmap_width; column++) {
          red = my_symbol->bitmap[i];
          green = my_symbol->bitmap[i + 1];
          blue = my_symbol->bitmap[i + 2];
          render_pixel(row, column, red, green, blue);
          i += 3;
     }
}

5.5 Setting Options
-------------------
So far our application is not very useful unless we plan to only make Code 128 
symbols and we don't mind that they only save to out.png. As with the CLI 
program, of course, these options can be altered. The way this is done is 
by altering the contents of the zint_symbol structure between the creation and 
encoding stages. The zint_symbol structure consists of the following variables: 

-------------------------------------------------------------------------------
Variable Name    | Type         | Meaning                     | Default Value
-------------------------------------------------------------------------------
symbology        | integer      | Symbol to use (see section  | BARCODE_CODE128
                 |              |    5.7).                    | 
height           | integer      | Symbol height. [1]          | 50
whitespace_width | integer      | Whtespace width.            | 0
border_width     | integer      | Border width.               | 0
output_options   | integer      | Set various output file     | (none)
                 |              |    parameters (see section  |
                 |              |    5.8). [2]                |
fgcolour         | character    | Foreground (ink) colour as  | "000000"
                 |    string    |    RGB hexadecimal string.  |
                 |              |    Must be 6 characters     |
                 |              |    followed by terminating  |
                 |              |    \0 character.            |
bgcolour         | character    | Background (paper) colour   | "ffffff"
                 |    string    |    as RGB hexadecimal       |
                 |              |    string. Must be 6 chara- |
                 |              |    ters followed by termin- |
                 |              |    ating \0 character.      |
outfile          | character    | Contains the name of the    | "out.png"
                 |    string    |    file to output a result- |
                 |              |    ing barcode symbol to.   |
                 |              |    Must end in .png, .gif,  |
                 |              |    .eps, .pcx, .svg or .txt |
option_1         | integer      | Symbol specific options.    | (automatic)
option_2         | integer      | Symbol specific options.    | (automatic)
option_3         | integer      | Symbol specific options.    | (automatic)
scale            | float        | Scale factor for adjusting  | 1.0
                 |              |    size of image.           |
input_mode       | integer      | Set encoding of input data  | UNICODE_MODE
                 |              |    (see section 5.9)        |
eci              | integer      | Extended Channel Interpre-  | 3
                 |              |    tation mode.             |
primary          | character    | Primary message data for    | NULL
                 |    string    |    more complex symbols.    |
text             | unsigned     | Human readable text, which  | NULL
                 |    character |    usually consists of in-  |
                 |    string    |    put data plus one more   |
                 |              |    check digit. Uses UTF-8  |
                 |              |    formatting.              |
show_hrt         | integer      | Set to 0 to hide text.      | 1
dot_size         | float        | Size of dots used in dotty  | 4.0 / 5.0
                 |              |    mode.                    |
rows             | integer      | Number of rows used by the  | (output only)
                 |              |    the symbol.              |
width            | integer      | Width of the generated sym- | (output only)
                 |              |    bol.                     |
encoding_data    | array of     | Representation of the       | (output only)
                 |    character |    encoded data.            |
                 |    strings   |                             |
row_height       | array of     | Representation of the       | (output only)
                 |    integers  |    height of a row.         |
errtxt           | character    | Error message in the event  | (output only)
                 |    string    |    that an error ocurred.   |
bitmap           | pointer to   | Pointer to stored bitmap    | (output only)
                 |    character |    image.                   |
                 |    array     |                             |
bitmap_width     | integer      | Width of stored bitmap      | (output only)
                 |              |    image (in pixels).       |
bitmap_height    | integer      | Height of stored bitmap     | (output only)
                 |              |    image (in pixels).       |
-------------------------------------------------------------------------------

To alter these values use the syntax shown in the example below. This code has 
the same result as the previous example except the output is now taller and 
plotted in green.

#include <stdio.h>
#include <zint.h>
#include <string.h>
int main(int argc, char **argv)
{
    struct zint_symbol *my_symbol;my_symbol = ZBarcode_Create();
    strcpy(my_symbol->fgcolour, "00ff00");
    my_symbol->height = 400;
    ZBarcode_Encode_and_Print(my_symbol, argv[1], 0, 0);
    ZBarcode_Delete(my_symbol);
    return 0;
}

5.6 Handling Errors
-------------------
If errors occur during encoding an integer value is passed back to the calling 
application. In addition the errtxt value is used to give a message detailing 
the nature of the error. The errors generated by Zint are given in the table 
below: 

-------------------------------------------------------------------------------
Return Value                 |  Meaning
-------------------------------------------------------------------------------
ZINT_WARN_INVALID_OPTION     |  One of the values in zint_struct was set
                             |     incorrectly but Zint has made a guess at
                             |     what it should have been and generated a
                             |     barcode accordingly.
ZINT_WARN_USES_ECI           |  Zint has automatically inserted an ECI 
                             |     character. The symbol may not be readable
                             |     with some readers.
ZINT_ERROR_TOO_LONG          |  The input data is too long or too short for the
                             |     selected symbology. No symbol has been
                             |     generated. 
ZINT_ERROR_INVALID_DATA      |  The data to be encoded includes characters which
                             |     are not permitted by the selected symbology
                             |     (e.g. alphabetic characters in an EAN
                             |     symbol). No symbol has been generated. 
ZINT_ERROR_INVALID_CHECK     |  An ISBN with an incorrect check digit has been 
                             |     entered. No symbol has been generated. 
ZINT_ERROR_INVALID_OPTION    |  One of the values in zint_struct was set
                             |     incorrectly and Zint was unable to guess what
                             |     it should have been. No symbol has been
                             |     generated. 
ZINT_ERROR_ENCODING_PROBLEM  |  A problem has occurred during encoding of the
                             |     data. This should never happen. Please
                             |     contact the developer if you encounter this
                             |     error. 
ZINT_ERROR_FILE_ACCESS       |  Zint was unable to open the requested output
                             |     file. This is usually a file permissions
                             |     problem.
ZINT_ERROR_MEMORY            |  Zint ran out of memory. This should only be a
                             |     problem with legacy systems.
-------------------------------------------------------------------------------

To catch errors use an integer variable as shown in the code below:

#include <stdio.h>
#include <zint.h>
#include <string.h>
int main(int argc, char **argv)
{
    struct zint_symbol *my_symbol;
    int error = 0;
    my_symbol = ZBarcode_Create();
    strcpy(my_symbol->fgcolour, "nonsense");
    error = ZBarcode_Encode_and_Print(my_symbol, argv[1], 0, 0);
    if(error != 0)
    {
    /* some error occurred */
        printf("%s\n", my_symbol->errtxt);
    }
    if(error > WARN_INVALID_OPTION)
    {
    /* stop now */
        ZBarcode_Delete(my_symbol);
    return 1;
    }
    /* otherwise carry on with the rest of the application */
    ZBarcode_Delete(my_symbol);
    return 0;
}

This code will exit with the appropriate message:

error: malformed foreground colour target

5.7 Specifying a Symbology
--------------------------
Symbologies can be specified by number or by name as shown in the following 
table. For example

symbol->symbology= BARCODE_LOGMARS;

means the same as

symbol->symbology = 50;

--------------------------------------------------------------------------------
Numeric | Name                    | Barcode Name
Value   | 
--------------------------------------------------------------------------------
1       | BARCODE_CODE11          | Code 11
2       | BARCODE_C25MATRIX       | Standard Code 2 of 5
3       | BARCODE_C25INTER        | Interleaved 2 of 5
4       | BARCODE_C25IATA         | Code 2 of 5 IATA
6       | BARCODE_C25LOGIC        | Code 2 of 5 Data Logic
7       | BARCODE_C25IND          | Code 2 of 5 Industrial
8       | BARCODE_CODE39          | Code 3 of 9 (Code 39)
9       | BARCODE_EXCODE39        | Extended Code 3 of 9 (Code 39+)
13      | BARCODE_EANX            | EAN
14      | BARCODE_EANX_CHK        | EAN + Check Digit
16      | BARCODE_EAN128          | GS1-128 (UCC.EAN-128)
18      | BARCODE_CODABAR         | Codabar
20      | BARCODE_CODE128         | Code 128 (automatic subset switching)
21      | BARCODE_DPLEIT          | Deutshe Post Leitcode
22      | BARCODE_DPIDENT         | Deutshe Post Identcode
23      | BARCODE_CODE16K         | Code 16K
24      | BARCODE_CODE49          | Code 49
25      | BARCODE_CODE93          | Code 93
28      | BARCODE_FLAT            | Flattermarken
29      | BARCODE_RSS14           | GS1 DataBar-14
30      | BARCODE_RSS_LTD         | GS1 DataBar Limited
31      | BARCODE_RSS_EXP         | GS1 DataBar Extended
32      | BARCODE_TELEPEN         | Telepen Alpha
34      | BARCODE_UPCA            | UPC A
35      | BARCODE_UPCA_CHK        | UPC A + Check Digit
37      | BARCODE_UPCE            | UPC E
38      | BARCODE_UPCE            | UPC E + Check Digit
40      | BARCODE_POSTNET         | PostNet
47      | BARCODE_MSI_PLESSEY     | MSI Plessey
49      | BARCODE_FIM             | FIM
50      | BARCODE_LOGMARS         | LOGMARS
51      | BARCODE_PHARMA          | Pharmacode One-Track
52      | BARCODE_PZN             | PZN
53      | BARCODE_PHARMA_TWO      | Pharmacode Two-Track
55      | BARCODE_PDF417          | PDF417
56      | BARCODE_PDF417TRUNC     | PDF417 Truncated
57      | BARCODE_MAXICODE        | Maxicode
58      | BARCODE_QRCODE          | QR Code
60      | BARCODE_CODE128B        | Code 128 (Subset B)
63      | BARCODE_AUSPOST         | Australia Post Standard Customer
66      | BARCODE_AUSREPLY        | Australia Post Reply Paid
67      | BARCODE_AUSROUTE        | Australia Post Routing
68      | BARCODE_AUSDIRECT       | Australia Post Redirection
69      | BARCODE_ISBNX           | ISBN (EAN-13 with verification stage)
70      | BARCODE_RM4SCC          | Royal Mail 4 State (RM4SCC)
71      | BARCODE_DATAMATRIX      | Data Matrix ECC200
72      | BARCODE_EAN14           | EAN-14
74      | BARCODE_CODABLOCKF      | Codablock-F
75      | BARCODE_NVE18           | NVE-18
76      | BARCODE_JAPANPOST       | Japanese Postal Code
77      | BARCODE_KOREAPOST       | Korea Post
79      | BARCODE_RSS14STACK      | GS1 DataBar-14 Stacked
80      | BARCODE_RSS14STACK_OMNI | GS1 DataBar-14 Stacked Omnidirectional
81      | BARCODE_RSS_EXPSTACK    | GS1 DataBar Expanded Stacked
82      | BARCODE_PLANET          | PLANET
84      | BARCODE_MICROPDF417     | MicroPDF417
85      | BARCODE_ONECODE         | USPS OneCode
86      | BARCODE_PLESSEY         | Plessey Code
87      | BARCODE_TELEPEN_NUM     | Telepen Numeric
89      | BARCODE_ITF14           | ITF-14
90      | BARCODE_KIX             | Dutch Post KIX Code
92      | BARCODE_AZTEC           | Aztec Code
93      | BARCODE_DAFT            | DAFT Code
97      | BARCODE_MICROQR         | Micro QR Code
98      | BARCODE_HIBC_128        | HIBC Code 128
99      | BARCODE_HIBC_39         | HIBC Code 39
102     | BARCODE_HIBC_39         | HIBC Data Matrix ECC200
104     | BARCODE_HIBC_DM         | HIBC QR Code
106     | BARCODE_HIBC_PDF        | HIBC PDF417
108     | BARCODE_HIBC_MICPDF     | HIBC MicroPDF417
112     | BARCODE_HIBC_AZTEC      | HIBC Aztec Code
115     | BARCODE_DOTCODE         | DotCode
116     | BARCODE_HANXIN          | Han Xin (Chinese Sensible) Code
128     | BARCODE_AZRUNE          | Aztec Runes
129     | BARCODE_CODE32          | Code 32
130     | BARCODE_EANX_CC         | Composite Symbol with EAN linear component
131     | BARCODE_EAN128_CC       | Composite Symbol with GS1-128 linear 
        |                         |    component
132     | BARCODE_RSS14_CC        | Composite Symbol with GS1 DataBar-14 linear 
        |                         |    component
133     | BARCODE_RSS_LTD_CC      | Composite Symbol with GS1 DataBar Limited 
        |                         |    component
134     | BARCODE_RSS_EXP_CC      | Composite Symbol with GS1 DataBar Extended 
        |                         |    component
135     | BARCODE_UPCA_CC         | Composite Symbol with UPC A linear component
136     | BARCODE_UPCE_CC         | Composite Symbol with UPC E linear component
137     | BARCODE_RSS14STACK_CC   | Composite Symbol with GS1 DataBar-14 
        |                         |    Stacked component
138     | BARCODE_RSS14_OMNI_CC   | Composite Symbol with GS1 DataBar-14 
        |                         |    Stacked Omnidirectional component
139     | BARCODE_RSS_EXPSTACK_CC | Composite Symbol with GS1 DataBar Expanded 
        |                         |    Stacked component
140     | BARCODE_CHANNEL         | Channel Code
141     | BARCODE_CODEONE         | Code One
142     | BARCODE_GRIDMATRIX      | Grid Matrix
--------------------------------------------------------------------------------

5.8 Adjusting other output options
----------------------------------
The output_options variable can be used to adjust various aspects of the output
file. To select more than one option from the table below simply add them together
when adjusting this value:

my_symbol->output_options += BARCODE_BIND + READER_INIT;

--------------------------------------------------------------------------------
Value               |  Effect
--------------------------------------------------------------------------------
0                   |  No options selected.
BARCODE_BIND        |  Boundary bars above and below the symbol and between
                    |     rows if stacking multiple symbols. [2]
BARCODE_BOX         |  Add a box surrounding the symbol and whitespace. [2]
BARCODE_STDOUT      |  Output the file to stdout.
READER_INIT         |  Add a reader initialisation symbol to the data before
                    |     encoding.
SMALL_TEXT          |  Use a smaller font for the human readable text.
BOLD_TEXT           |  Embolden the human readable text.
CMYK_COLOUR         |  Select the CMYK colour space option for encapsulated
                    |      PostScript files.
BARCODE_DOTTY_MODE  |  Plot a matrix symbol using dots rather than squares.
--------------------------------------------------------------------------------

5.9 Setting the Input Mode
--------------------------
The way in which the input data is encoded can be set using the input_mode 
property. Valid values are shown in the table below. 

-----------------------------------------------------------------------------
Value         |  Effect
-----------------------------------------------------------------------------
DATA_MODE     |  Uses full ASCII range interpreted as Latin-1 or binary data.
UNICODE_MODE  |  Uses pre-formatted UTF-8 input.
GS1_MODE      |  Encodes GS1 data using FNC1 characters.
-----------------------------------------------------------------------------

5.10 Verifying Symbology Availability
-------------------------------------
An additional function available in the API is defined as:

int ZBarcode_ValidID(int symbol_id);

This function allows you to check whether a given symbology is available. A 
non-zero return value indicates that the given symbology is available. For 
example:

if(ZBarcode_ValidID(BARCODE_PDF417) != 0) {
    printf("PDF417 available");
} else {
    printf("PDF417 not available");
}

[1] This value is ignored for Australia Post 4-State Barcodes, PostNet, PLANET, 
USPS OneCode, RM4SCC, PDF417, Data Matrix ECC200, Maxicode, QR Code, GS1 
DataBar-14 Stacked, PDF417 and MicroPDF417 - all of which have a fixed height.

[2] This value is ignored for Code 16k, Codablock-F and ITF-14 symbols.

6. Types of Symbology
=====================
6.1 One-Dimensional Symbols
---------------------------
One-Dimensional Symbols are what most people associate with the term barcode. 
They consist of a number of bars and a number of spaces of differing widths.

6.1.1 Code 11
-------------
Developed by Intermec in 1977, Code 11 is similar to Code 2 of 5 Matrix and is 
primarily used in telecommunications. The symbol can encode any length string 
consisting of the digits 0-9 and the dash character (-). One modulo-11 check 
digit is calculated.

6.1.2 Code 2 of 5
-----------------
Code 2 of 5 is a family of one-dimensional symbols, 8 of which are supported by 
Zint. Note that the names given to these standards alters from one source to 
another so you should take care to ensure that you have the right barcode type 
before using these standards.

6.1.2.1 Standard Code 2 of 5
----------------------------
Also known as Code 2 of 5 Matrix is a self-checking code used in industrial 
applications and photo development. Standard Code 2 of 5 will encode any length 
numeric input (digits 0-9).

6.1.2.2 IATA Code 2 of 5
------------------------
Used for baggage handling in the air-transport industry by the International 
Air Transport Agency, this self-checking code will encode any length numeric input 
(digits 0-9) and does not include a check digit.

6.1.2.3 Industrial Code 2 of 5
------------------------------
Industrial Code 2 of 5 can encode any length numeric input (digits 0-9) and 
does not include a check digit.

6.1.2.4 Interleaved Code 2 of 5
-------------------------------
This self-checking symbology encodes pairs of numbers, and so can only encode 
an even number of digits (0-9). If an odd number of digits is entered a leading 
zero is added by Zint. No check digit is added.

6.1.2.5 Code 2 of 5 Data Logic
------------------------------
Data Logic does not include a check digit and can encode any length numeric 
input (digits 0-9).

6.1.2.6 ITF-14
--------------
ITF-14, also known as UPC Shipping Container Symbol or Case Code is based on 
Interleaved Code 2 of 5 and requires a 13 digit numeric input (digits 0-9). One 
modulo-10 check digit is added by Zint.

6.1.2.7 Deutsche Post Leitcode
------------------------------
Leitcode is based on Interleaved Code 2 of 5 and is used by Deutsche Post for 
mailing purposes. Leitcode requires a 13-digit numerical input and includes a 
check digit.

6.1.2.8 Deutsche Post Identcode
-------------------------------
Identcode is based on Interleaved Code 2 of 5 and is used by Deutsche Post for 
mailing purposes. Identcode requires an 11-digit numerical input and includes a 
check digit.

6.1.3 Universal Product Code (EN 797)
-------------------------------------
6.1.3.1 UPC Version A
---------------------
UPC-A is used in the United States for retail applications. The symbol requires 
an 11 digit article number. The check digit is calculated by Zint. In addition 
EAN-2 and EAN-5 add-on symbols can be added using the + character. For example, 
to draw a UPC-A symbol with the data 72527270270 with an EAN-5 add-on showing 
the data 12345 use the command:

zint --barcode=34 -d 72527270270+12345

or encode a data string with the + character included:

my_symbol->symbology = BARCODE_UPCA;

error = ZBarcode_Encode_and_Print(my_symbol, "72527270270+12345");

If your input data already includes the check digit symbology 35 can be used
which takes a 12 digit input and validates the check digit before encoding.

6.1.3.2 UPC Version E
---------------------
UPC-E is a zero-compressed version of UPC-A developed for smaller packages. The 
code requires a 6 digit article number (digits 0-9). The check digit is 
calculated by Zint. EAN-2 and EAN-5 add-on symbols can be added using the + 
character as with UPC-A. In addition Zint also supports Number System 1 
encoding by entering a 7-digit article number stating with the digit 1. For
example:

zint --barcode=37 -d 1123456

or

my_symbol->symbology = BARCODE_UPCE;

error = ZBarcode_Encode_and_Print(my_symbol, "1123456");

If your input data already includes the check digit symbology 38 can be used
which takes a 7 or 8 digit input and validates the check digit before encoding.

6.1.4 European Article Number (EN 797)
--------------------------------------
6.1.4.1 EAN-2, EAN-5, EAN-8 and EAN-13
--------------------------------------
The EAN system is used in retail across Europe and includes standards for EAN-2 
and EAN-5 add-on codes, EAN-8 and EAN-13 which encode 2, 5, 7 or 12 digit 
numbers respectively. Zint will decide which symbology to use depending on the 
length of the input data. In addition EAN-2 and EAN-5 add-on symbols can be 
added using the + symbol as with UPC symbols. For example:

zint --barcode=13 -d 54321

will encode a stand-alone EAN-5, whereas

zint --barcode=13 -d 7432365+54321

will encode an EAN-8 symbol with an EAN-5 add-on. As before these results can 
be achieved using the API:

my_symbol->symbology = BARCODE_EANX;

error = ZBarcode_Encode_and_Print(my_symbol, "54321");

error = ZBarcode_Encode_and_Print(my_symbol, "7432365+54321");

All of the EAN symbols include check digits which are added by Zint.

If you are encoding an EAN-8 or EAN-13 symbol and your data already includes
the check digit then you can use symbology 14 which takes an 8 or 13 digit input
and validates the check digit before encoding.

6.1.4.2 SBN, ISBN and ISBN-13
-----------------------------
EAN-13 symbols (also known as Bookland EAN-13) can also be produced from 
9-digit SBN, 10-digit ISBN or 13-digit ISBN-13 data. The relevant check digit needs
to be present in the input data and will be verified before the symbol is 
generated. In addition EAN-2 and EAN-5 add-on symbols can be added using the + 
symbol as with UPC symbols.

6.1.5 Plessey
-------------
Also known as Plessey Code, this symbology was developed by the Plessey Company 
Ltd. in the UK. The symbol can encode any length data consisting of digits 
(0-9) or letters A-F and includes a CRC check digit. 

6.1.6 MSI Plessey
-----------------
Based on Plessey and developed by MSE Data Corporation, MSI Plessey is 
available with a range of check digit options available by setting option_2 or 
by using the --ver= switch. Any length numeric (digits 0-9) input can be 
encoded. The table below shows the options available: 

-------------------------------------------
Value of option_2  |  Check Digits
-------------------------------------------
0                  |  None
1                  |  Modulo-10
2                  |  Modulo-10 & Modulo-10
3                  |  Modulo-11
4                  |  Modulo-11 & Modulo-10
-------------------------------------------

6.1.7 Telepen
-------------
6.1.7.1 Telepen Alpha
---------------------
Telepen Alpha was developed by SB Electronic Systems Limited and can encode any 
length of ASCII text input. Telepen includes a modulo-127 check digit.

6.1.7.2 Telepen Numeric
-----------------------
Telepen Numeric allows compression of numeric data into a Telepen symbol. Data 
can consist of pairs of numbers or pairs consisting of a numerical digit 
followed an X character. For example: 466333 and 466X33 are valid codes whereas 
46X333 is not (the digit pair "X3" is not valid). Telepen Numeric includes a
modulo-127 check digit which is added by Zint. 

6.1.8 Code 39
-------------
6.1.8.1 Standard Code 39 (ISO 16388)
------------------------------------
Standard Code 39 was developed in 1974 by Intermec. Input data can be of any 
length and can include the characters 0-9, A-Z, dash (-), full stop (.), space, 
asterisk (*), dollar ($), slash (/), plus (+) and percent (%). The standard 
does not require a check digit but a modulo-43 check digit can be added if 
required by setting option_2 = 1 or using --ver=1.

6.1.8.2 Extended Code 39
------------------------
Also known as Code 39e and Code39+, this symbology expands on Standard Code 39 
to provide support to the full ASCII character set. The standard does not 
require a check digit but a modulo-43 check digit can be added if required by 
setting option_2 = 1 or using --ver=1.

6.1.8.3 Code 93
---------------
A variation of Extended Code 39, Code 93 also supports full ASCII text. Two 
check digits are added by Zint.

6.1.8.4 PZN
-----------
PZN is a Code 39 based symbology used by the pharmaceutical industry in 
Germany. PZN encodes a 6 digit number to which Zint will add a modulo-10
check digit.

6.1.8.5 LOGMARS
---------------
LOGMARS (Logistics Applications of Automated Marking and Reading Symbols) is a 
variation of the Code 39 symbology used by the US Department of Defence. 
LOGMARS encodes the same character set as Standard Code 39 and adds a modulo-43 
check digit.

6.1.8.6 Code 32
---------------
A variation of Code 39 used by the Italian Ministry of Health ("Ministero della 
Sanità") for encoding identifiers on pharmaceutical products. This symbology
requires a numeric input up to 8 digits in length. A check digit is added by Zint.

6.1.8.7 HIBC Code 39
--------------------
This option adds a leading '+' character and a trailing modulo-49 check digit 
to a standard Code 39 symbol as required by the Health Industry Barcode 
standards. 

6.1.9 Codabar (EN 798)
----------------------
Also known as NW-7, Monarch, ABC Codabar, USD-4, Ames Code and Code 27, this 
symbology was developed in 1972 by Monarch Marketing Systems for retail 
purposes. The American Blood Commission adopted Codabar in 1977 as the standard 
symbology for blood identification. Codabar can encode any length string 
starting and ending with the letters A-D and containing between these letters 
the numbers 0-9, dash (-), dollar ($), colon (:), slash (/), full stop (.) or 
plus (+). No check digit is generated.

6.1.10 Pharmacode
-----------------
Developed by Laetus, Pharmacode is used for the identification of 
pharmaceuticals. The symbology is able to encode whole numbers between 3 and 
131070. 

6.1.11 Code 128
---------------
6.1.11.1 Standard Code 128 (ISO 15417)
--------------------------------------
One of the most ubiquitous one-dimensional barcode symbologies, Code 128 was 
developed in 1981 by Computer Identics. This symbology supports full ASCII text 
and uses a three-mode system to compress the data into a smaller symbol. Zint 
automatically switches between modes and adds a modulo-103 check digit. Code 
128 is the default barcode symbology used by Zint. In addition Zint supports 
the encoding of Latin-1 (non-English) characters in Code 128 symbols [1]. The 
Latin-1 character set is shown in Appendix A.

6.1.11.2 Code 128 Subset B
--------------------------
It is sometimes advantageous to stop Code 128 from using subset mode C which 
compresses numerical data. The BARCODE_CODE128B option (symbology 60) 
suppresses mode C in favour of mode B.

6.1.11.3 GS1-128
----------------
A variation of Code 128 also known as UCC/EAN-128, this symbology is defined by 
the GS1 General Specification. Application Identifiers (AIs) should be entered 
using [square bracket] notation. These will be converted to (round brackets) 
for the human readable text. This will allow round brackets to be used in the 
data strings to be encoded. Fixed length data should be entered at the 
appropriate length for correct encoding (see Appendix C). GS1-128 does not 
support extended ASCII characters. Check digits for GTIN data (AI 01) are not 
generated and need to be included in the input data. The following is an example
of a valid GS1-128 input:

zint --barcode=16 -d "[01]98898765432106[3202]012345[15]991231"

6.1.11.4 EAN-14
---------------
A shorter version of GS1-128 which encodes GTIN data only. A 13 digit number is 
required. The GTIN check digit and AI (01) are added by Zint.

6.1.11.5 NVE-18
---------------
A variation of Code 128 the "Nummber der Versandeinheit" standard includes both 
modulo-10 and modulo-103 check digits. NVE-18 requires a 17 digit numerical 
input and check digits are added by Zint.

6.1.11.6 HIBC Code 128
----------------------
This option adds a leading '+' character and a trailing modulo-49 check digit 
to a standard Code 128 symbol as required by the Health Industry Barcode 
standards. 

6.1.12 GS1 DataBar (ISO 24724)
------------------------------
Also known as RSS (Reduced Spaced Symbology) these symbols are due to replace 
GS1-128 symbols in accordance with the GS1 General Specification. If a GS1
DataBar symbol is to be printed with a 2D component as specified in ISO 24723
set option_1 = 2 or use the option --mode=2 at the command prompt. See section
6.3 of this manual to find out how to generate DataBar symbols with 2D components.

6.1.12.1 DataBar-14 and DataBar-14 Truncated
--------------------------------------------
Also known as RSS-14 this standard encodes a 13 digit item code. A check digit 
and application identifier of (01) are added by Zint. To produce a truncated
symbol set the symbol height to a value between 32 and 13. Normal DataBar-14
symbols should have a height of 33 or greater.

6.1.12.2 DataBar Limited
------------------------
Also known as RSS Limited this standard encodes a 13 digit item code and can be 
used in the same way as DataBar-14 above. DataBar Limited, however, is limited 
to data starting with digits 0 and 1 (i.e. numbers in the range 0 to 
1999999999999). As with DataBar-14 a check digit and application identifier of 
(01) are added by Zint.

6.1.12.3 DataBar Expanded
-------------------------
Also known as RSS Expanded this is a variable length symbology capable of 
encoding data from a number of AIs in a single symbol. AIs should be encased in 
[square brackets] in the input data. This will be converted to (rounded 
brackets) before it is included in the human readable text attached to the 
symbol. This method allows the inclusion of rounded brackets in the data to be 
encoded. GTIN data (AI 01) should also include the check digit data as this is 
not calculated by Zint when this symbology is encoded. Fixed length data should
be entered at the appropriate length for correct encoding (see Appendix C). The
following is an example of a valid DataBar Expanded input:

zint --barcode=31 -d "[01]98898765432106[3202]012345[15]991231" 

6.1.13 Korea Post Barcode
-------------------------
The Korean Postal Barcode is used to encode a six-digit number and includes one 
check digit. 

6.1.14 Channel Code
-------------------
A highly compressed symbol for numeric data. The number of channels in the 
symbol can be between 3 and 8 and this can be specified by setting the value of 
option_2. It can also be determined by the length of the input data e.g. a 
three character input string generates a 4 channel code by default. The maximum 
values permitted depend on the number of channels used as shown in the table 
below: 

--------------------------------------------
Channels  |  Minimum Value  |  Maximum Value
--------------------------------------------
3         |  00             |  26
4         |  000            |  292
5         |  0000           |  3493
6         |  00000          |  44072
7         |  000000         |  576688
8         |  0000000        |  7742862
--------------------------------------------

6.2 Stacked Symbologies
-----------------------
6.2.1 Basic Symbol Stacking
---------------------------
An early innovation to get more information into a symbol, used primarily in 
the vehicle industry, is to simply stack one-dimensional codes on top of each 
other. This can be achieved at the command prompt by giving more than one set 
of input data. For example

zint -d 'This' -d 'That'

will draw two Code 128 symbols, one on top of the other. The same result can be 
achieved using the API by executing the ZBarcode_Encode() function more than 
once on a symbol. For example:

my_symbol->symbology = BARCODE_CODE128;

error = ZBarcode_Encode(my_symbol, "This");

error = ZBarcode_Encode(my_symbol, "That");

error = ZBarcode_Print(my_symbol);

A more sophisticated method is to use some type of line indexing which 
indicates to the barcode reader which order the symbols should be read. This is 
demonstrated by the symbologies below.

6.2.2 Codablock-F
-----------------
This is a stacked symbology based on Code 128 which can encode ASCII code set
data up to a maximum length of 2725 characters. The width of the Codablock-F
symbol can be set using the --cols= option at the command line or option_2.
Alternatively the height (number of rows) can be set using the --rows= option
at the command line or by setting option_1. Zint does not support encoding of
GS1 data in Codablock-F symbols.

6.2.3 Code 16k (EN 12323)
-------------------------
Code 16k uses a Code 128 based system which can stack up to 16 rows in a block.
This gives a maximum data capacity of 77 characters or 154 numerical digits and
includes two modulo-107 check digits. Code 16k also supports extended ASCII
character encoding in the same manner as Code 128. 

6.2.4 PDF417 (ISO 15438)
------------------------
Heavily used in the parcel industry, the PDF417 symbology can encode a vast 
amount of data into a small space. Zint supports encoding up to the ISO 
standard maximum symbol size of 925 codewords which (at error correction level 
0) allows a maximum data size of 1850 text characters, or 2710 digits. The 
width of the generated PDF417 symbol can be specified at the command line using 
the --cols switch followed by a number between 1 and 30, and the amount of 
check digit information can be specified by using the --security switch 
followed by a number between 0 and 8 where the number of codewords used for 
check information is determined by 2^(value + 1). If using the API these values 
are assigned to option_2 and option_1 respectively. The default level of check 
information is determined by the amount of data being encoded. This symbology 
uses Latin-1 character encoding by default but also supports the ECI encoding 
mechanism. A separate symbology ID can be used to encode Health Industry 
Barcode (HIBC) data which adds a leading '+' character and a modulo-49 check 
digit to the encoded data. 

6.2.5 Compact PDF417
--------------------
Also known as truncated PDF417. Options are the same as for PDF417 above.

6.2.6 MicroPDF417 (ISO 24728)
-----------------------------
A variation of the PDF417 standard, MicroPDF417 is intended for applications 
where symbol size needs to be kept to a minimum. 34 predefined symbol sizes are 
available with 1 - 4 columns and 4 - 44 rows. The maximum size MicroPDF417 
symbol can hold 250 alphanumeric characters or 366 digits. The amount of error 
correction used is dependent on symbol size. The number of columns used can be 
determined using the --cols switch or option_2 as with PDF417. This symbology 
uses Latin-1 character encoding by default but also supports the ECI encoding 
mechanism. A separate symbology ID can be used to encode Health Industry 
Barcode (HIBC) data which adds a leading '+' character and a modulo-49 check 
digit to the encoded data. 

6.2.7 GS1 DataBar-14 Stacked (ISO 24724)
----------------------------------------
A stacked variation of the GS1 DataBar-14 symbol requiring the same input (see 
section 6.1.12.1). The height of this symbol is fixed. The data is encoded in 
two rows of bars with a central finder pattern. This symbol can be generated 
with a two-dimensional component to make a composite symbol. 

6.2.8 GS1 DataBar-14 Stacked Omnidirectional (ISO 24724)
--------------------------------------------------------
Another variation of the GS1 DataBar-14 symbol requiring the same input (see 
section 6.1.12.1). The data is encoded in two rows of bars with a central 
finder pattern. This symbol can be generated with a two-dimensional component 
to make a composite symbol. 

6.2.9 GS1 DataBar Expanded Stacked (ISO 24724)
----------------------------------------------
A stacked variation of the GS1 DataBar Expanded symbol for smaller packages. 
Input is the same as for GS1 DataBar Expanded (see section 6.1.12.3). In 
addition the width of the symbol can be altered using the --cols switch or 
option_2. In this case the number of columns relates to the number of character 
pairs on each row of the symbol. This symbol can be generated with a two-
dimensional component to make a composite symbol. For symbols with a 2D component
the number of columns must be at least 2.

6.2.10 Code 49
-------------
Developed in 1987 at Intermec, Code 49 is a cross between UPC and Code 39. It 
it one of the earliest stacked symbologies and influenced the design of Code 
16K a few years later. It supports full 7-bit ASCII input up to a maximum of 49 
characters or 81 numeric digits. GS1 data encoding is also supported. 

6.3 Composite Symbols (ISO 24723)
---------------------------------
Composite symbols employ a mixture of components to give more comprehensive 
information about a product. The permissible contents of a composite symbol is 
determined by the terms of the GS1 General Specification. Composite symbols 
consist of a linear component which can be an EAN, UPC, GS1-128 or GS1 DataBar 
symbol, a 2D component which is based on PDF417 or MicroPDF417, and a separator 
pattern. The type of linear component to be used is determined using the -b or 
--barcode= switch or by adjusting symbol->symbology as with other encoding 
methods. Valid values are shown below. 

--------------------------------------------------------------------------------
Numeric | Name                    | Barcode Name
Value   | 
--------------------------------------------------------------------------------
130     | BARCODE_EANX_CC         | Composite Symbol with EAN linear component
131     | BARCODE_EAN128_CC       | Composite Symbol with GS1-128 linear 
        |                         |    component
132     | BARCODE_RSS14_CC        | Composite Symbol with GS1 DataBar-14 linear 
        |                         |    component
133     | BARCODE_RSS_LTD_CC      | Composite Symbol with GS1 DataBar Limited 
        |                         |    component
134     | BARCODE_RSS_EXP_CC      | Composite Symbol with GS1 DataBar Extended 
        |                         |    component
135     | BARCODE_UPCA_CC         | Composite Symbol with UPC A linear component
136     | BARCODE_UPCE_CC         | Composite Symbol with UPC E linear component
137     | BARCODE_RSS14STACK_CC   | Composite Symbol with GS1 DataBar-14 
        |                         |    Stacked component
138     | BARCODE_RSS14_OMNI_CC   | Composite Symbol with GS1 DataBar-14 
        |                         |    Stacked Omnidirectional component
139     | BARCODE_RSS_EXPSTACK_CC | Composite Symbol with GS1 DataBar Expanded 
        |                         |    Stacked component
--------------------------------------------------------------------------------

The data to be encoded in the linear component of a composite symbol should be 
entered into a primary string with the data for the 2D component being entered 
in the normal way. To do this at the command prompt use the --primary= command. 
For example:

zint -b 130 --mode=1 --primary=331234567890 -d "[99]1234-abcd"

This creates an EAN-13 linear component with the data "331234567890" and a 2D 
CC-A (see below) component with the data "(99)1234-abcd". The same results can 
be achieved using the API as shown below:

my_symbol->symbology = 130;

my_symbol->option_1 = 1;

strcpy(my_symbol->primary, "331234567890");

ZBarcode_Encode_and_Print(my_symbol, "[99]1234-abcd");

EAN-2 and EAN-5 add-on data can be used with EAN and UPC symbols using the + 
symbol as described in section 6.1.3 and 5.1.4.

The 2D component of a composite symbol can use one of three systems: CC-A, CC-B 
and CC-C as described below. The 2D component type can be selected 
automatically by Zint dependant on the length of the input string. 
Alternatively the three methods can be accessed using the --mode= prompt 
followed by 1, 2 or 3 for CC-A, CC-B or CC-C respectively, or by using the 
option_1 variable as shown above. 

6.3.1 CC-A
----------
This system uses a variation of MicroPDF417 which optimised to fit into a small 
space. The size of the 2D component and the amount of error correction is 
determined by the amount of data to be encoded and the type of linear component 
which is being used. CC-A can encode up to 56 numeric digits or an alphanumeric 
string of shorter length. To select CC-A use --mode=1.

6.3.2 CC-B
----------
This system uses MicroPDF417 to encode the 2D component. The size of the 2D 
component and the amount of error correction is determined by the amount of 
data to be encoded and the type of linear component which is being used. CC-B 
can encode up to 338 numeric digits or an alphanumeric string of shorter 
length. To select CC-B use --mode=2.

6.3.3 CC-C
----------
This system uses PDF417 and can only be used in conjunction with a GS1-128 
linear component. CC-C can encode up to 2361 numeric digits or an alphanumeric 
string of shorter length. To select CC-C use --mode=3. 

6.4 Two-Track Symbols
---------------------
6.4.1 Two-Track Pharmacode
--------------------------
Developed by Laetus, Pharmacode Two-Track is an alternative system to 
Pharmacode One-Track used for the identification of pharmaceuticals. The 
symbology is able to encode whole numbers between 4 and 64570080.

6.4.2 PostNet
-------------
Used by the United States Postal Service until 2009, the PostNet barcode was 
used for encoding zip-codes on mail items. PostNet uses numerical input data 
and includes a modulo-10 check digit. While Zint will encode PostNet symbols of 
any length, standard lengths as used by USPS were PostNet6 (5 digits ZIP 
input), PostNet10 (5 digit ZIP + 4 digit user data) and PostNet12 (5 digit ZIP 
+ 6 digit user data).

6.4.3 PLANET
------------
Used by the United States Postal Service until 2009, the PLANET (Postal Alpha 
Numeric Encoding Technique) barcode was used for encoding routing data on mail 
items. Planet uses numerical input data and includes a modulo-10 check digit. 
While Zint will encode PLANET symbols of any length, standard lengths used by 
USPS were Planet12 (11 digit input) and Planet14 (13 digit input). 

6.5 4-State Postal Codes
------------------------
6.5.1 Australia Post 4-State Symbols
------------------------------------
6.5.1.1 Customer Barcodes
-------------------------
Australia Post Standard Customer Barcode, Customer Barcode 2 and Customer 
Barcode 3 are 37-bar, 52-bar and 67-bar specifications respectively, developed 
by Australia Post for printing Delivery Point ID (DPID) and customer 
information on mail items. Valid data characters are 0-9, A-Z, a-z, space and 
hash (#). A Format Control Code (FCC) is added by Zint and should not be 
included in the input data. Reed-Solomon error correction data is generated by 
Zint. Encoding behaviour is determined by the length of the input data 
according to the formula shown in the following table: 

-----------------------------------------------------------------
Input  |  Required Input Format    |  Symbol  |  FCC  |  Encoding
Length |                           |  Length  |       |  Table
-----------------------------------------------------------------
8      |  99999999                 |  37-bar  |  11   |  None
13     |  99999999AAAAA            |  52-bar  |  59   |  C
16     |  9999999999999999         |  52-bar  |  59   |  N
18     |  99999999AAAAAAAAAA       |  67-bar  |  62   |  C
23     |  99999999999999999999999  |  67-bar  |  62   |  N
-----------------------------------------------------------------

6.5.1.2 Reply Paid Barcode
--------------------------
A Reply Paid version of the Australia Post 4-State Barcode (FCC 45) which 
requires an 8-digit DPID input.

6.5.1.3 Routing Barcode
-----------------------
A Routing version of the Australia Post 4-State Barcode (FCC 87) which requires 
an 8-digit DPID input.

6.5.1.4 Redirect Barcode
------------------------
A Redirection version of the Australia Post 4-State Barcode (FCC 92) which 
requires an 8-digit DPID input. 

6.5.2 Dutch Post KIX Code
-------------------------
This Symbology is used by Royal Dutch TPG Post (Netherlands) for Postal code 
and automatic mail sorting. Data input can consist of numbers 0-9 and letters 
A-Z and needs to be 11 characters in length. No check digit is included.

6.5.3 Royal Mail 4-State Country Code (RM4SCC)
----------------------------------------------
The RM4SCC standard is used by the Royal Mail in the UK to encode postcode and 
customer data on mail items. Data input can consist of numbers 0-9 and letters 
A-Z and usually includes delivery postcode followed by house number. For 
example "W1J0TR01" for 1 Picadilly Circus in London. Check digit data is 
generated by Zint.

6.5.4 USPS OneCode
------------------
Also known as the Intelligent Mail Barcode and used in the US by the United 
States Postal Service (USPS), the OneCode system replaced the PostNet and 
PLANET symbologies in 2009. OneCode is a fixed length (65-bar) symbol which 
combines routing and customer information in a single symbol. Input data 
consists of a 20 digit tracking code, followed by a dash (-), followed by a 
delivery point zip-code which can be 0, 5, 9 or 11 digits in length. For 
example all of the following inputs are valid data entries:

"01234567094987654321"

"01234567094987654321-01234"

"01234567094987654321-012345678"

"01234567094987654321-01234567891"

6.5.5 Japanese Postal Code
--------------------------
Used for address data on mail items for Japan Post. Accepted values are 0-9, 
A-Z and Dash (-). A modulo 19 check digit is added by Zint.

6.6 Two-Dimensional Matrix Symbols
----------------------------------
6.6.1 Data Matrix ECC200 (ISO 16022)
------------------------------------
Also known as Semacode this symbology was developed in 1989 by Acuity CiMatrix 
in partnership with the US DoD and NASA. The symbol can encode a large amount 
of data in a small area. Data Matrix ECC200 can encode characters in the 
Latin-1 set by default but also supports encoding using other character sets 
using the ECI mechanism. It can also encode GS1 data. The size of the 
generated symbol can also be adjusted using the --vers= option or by setting 
option_2 as shown in the table below. A separate symbology ID can be used to 
encode Health Industry Barcode (HIBC) data which adds a leading '+' character 
and a modulo-49 check digit to the encoded data. Note that only ECC200 encoding 
is supported, the older standards have now been removed from Zint. 

---------------------
Input  |  Symbol Size
---------------------
1      |  10 x 10
2      |  12 x 12
3      |  14 x 14
4      |  16 x 16
5      |  18 x 18
6      |  20 x 20
7      |  22 x 22
8      |  24 x 24
9      |  26 x 26
10     |  32 x 32
11     |  36 x 36
12     |  40 x 40
13     |  44 x 44
14     |  48 x 48
15     |  52 x 52
16     |  64 x 64
17     |  72 x 72
18     |  80 x 80
19     |  88 x 88
20     |  96 x 96
21     |  104 x 104
22     |  120 x 120
23     |  132 x 132
24     |  144 x 144
25     |  8 x 18
26     |  8 x 32
28     |  12 x 26
28     |  12 x 36
29     |  16 x 36
30     |  16 x 48
---------------------

To force Zint only to use square symbols (versions 1-24) at the command line 
use the option --square and when using the API set the value option_3 = 
DM_SQUARE.

Data Matrix Rectangular Extension (DMRE) codes may be generated with the 
following values as before:

---------------------
Input  |  Symbol Size
---------------------
31     |  8 x 48
32     |  8 x 64
33     |  12 x 64
34     |  16 x 64
35     |  24 x 32
36     |  24 x 36
37     |  24 x 48
38     |  24 x 64
39     |  26 x 32
40     |  26 x 40
41     |  26 x 48
42     |  26 x 64
---------------------

DMRE symbol sizes may be activated in automatic size mode using the option 
--dmre or by the API option_3 = DM_DMRE

6.6.2 QR Code (ISO 18004)
-------------------------
Also known as Quick Response Code this symbology was developed by Denso. Four 
levels of error correction are available using the --security= option or by
setting option_1 as shown in the following table. 

-------------------------------------------------------------------------
Input  |  ECC Level    |  Error Correction Capacity  |  Recovery Capacity
-------------------------------------------------------------------------
1      |  L (default)  |  Approx 20% of symbol       |  Approx 7%
2      |  M            |  Approx 37% of symbol       |  Approx 15%
3      |  Q            |  Approx 55% of symbol       |  Approx 25%
4      |  H            |  Approx 65% of symbol       |  Approx 30%
-------------------------------------------------------------------------

The size of the symbol can be set by using the --vers= option or setting 
option_2 to the QR Code version required (1-40). The size of symbol generated 
is shown in the table below. 

---------------------
Input  |  Symbol Size
---------------------
1      |  21 x 21
2      |  25 x 25
3      |  29 x 29
4      |  33 x 33
5      |  37 x 37
6      |  41 x 41
7      |  45 x 45
8      |  49 x 49
9      |  53 x 53
10     |  57 x 57
11     |  61 x 61
12     |  65 x 65
13     |  69 x 69
14     |  73 x 73
15     |  77 x 77
16     |  81 x 81
17     |  85 x 85
18     |  89 x 89
19     |  93 x 93
20     |  97 x 97
21     |  101 x 101
22     |  105 x 105
23     |  109 x 109
24     |  113 x 113
25     |  117 x 117
26     |  121 x 121
28     |  125 x 125
28     |  129 x 129
29     |  133 x 133
30     |  137 x 137
31     |  141 x 141
32     |  145 x 145
33     |  149 x 149
34     |  153 x 153
35     |  157 x 157
36     |  161 x 161
38     |  165 x 165
38     |  169 x 169
39     |  173 x 173
40     |  177 x 177
---------------------

The maximum capacity of a (version 40) QR Code symbol is 7089 numeric digits, 
4296 alphanumeric characters or 2953 bytes of data. QR Code symbols can also be 
used to encode GS1 data. QR Code symbols can by default encode characters in 
the Latin-1 set and Kanji characters which are members of the Shift-JIS 
encoding scheme. In addition QR Code supports using other character sets using 
the ECI mechanism. Input should usually be entered as Unicode (UTF-8) with 
conversion to Shift-JIS being carried out by Zint. A separate symbology ID can
be used to encode Health Industry Barcode (HIBC) data which adds a leading '+'
character and a modulo-49 check digit to the encoded data. 

6.6.3 Micro QR Code (ISO 18004)
-------------------------------
A miniature version of the QR Code symbol for short messages. ECC levels can be 
selected as for QR Code (above). QR Code symbols can encode characters in the 
Latin-1 set and Kanji characters which are members of the Shift-JIS encoding 
scheme. Input should be entered as a UTF-8 stream with conversion to Shift-JIS 
being carried out automatically by Zint. A preferred symbol size can be 
selected by using the --vers= option or by setting option_2 although the actual 
version used by Zint may be different if required by the input data. The table 
below shows the possible sizes: 

---------------------------------
Input  |  Version  |  Symbol Size
---------------------------------
1      |  M1       |  11 x 11
2      |  M2       |  13 x 13
3      |  M3       |  15 x 15
4      |  M4       |  17 x 17
---------------------------------

6.6.4 Maxicode (ISO 16023)
--------------------------
Developed by UPS the Maxicode symbology employs a grid of hexagons surrounding 
a 'bulls-eye' finder pattern. This symbology is designed for the identification 
of parcels. Maxicode symbols can be encoded in one of five modes. In modes 2 
and 3 Maxicode symbols are composed of two parts named the primary and 
secondary messages. The primary message consists of a structured data field 
which includes various data about the package being sent and the secondary 
message usually consists of address data in a data structure. The format of the 
primary message required by Zint is given in the following table: 

----------------------------------------------------------------------------
Characters | Meaning
----------------------------------------------------------------------------
1 - 9      | Postcode data which can consist of up to 9 digits (for mode 2) 
           |    or up to 6 alphanumeric characters (for mode 3). Remaining 
           |    unused characters should be filled with the SPACE character
           |    (ASCII 32). 
10 - 12    | Three digit country code according to ISO 3166 (see Appendix B)
13 - 15    | Three digit service code. This depends on your parcel courier. 
----------------------------------------------------------------------------

The primary message can be set at the command prompt using the --primary= switch.
The secondary message uses the normal data entry method. For example:

zint -o test.eps -b 57 --primary='999999999840012' -d 'Secondary Message Here'

When using the API the primary message must be placed in the symbol->primary 
string. The secondary is entered in the same way as described in section 5.2. 
When either of these modes is selected Zint will analyse the primary message 
and select either mode 2 or mode 3 as appropriate.

Modes 4 to 6 can be accessed using the --mode= switch or by setting option_1. 
Modes 4 to 6 do not require a primary message. For example:

zint -o test.eps -b 57 --mode=4 -d 'A MaxiCode Message in Mode 4'

Mode 6 is reserved for the maintenance of scanner hardware and should not be 
used to encode user data.

This symbology uses Latin-1 character encoding by default but also supports the 
ECI encoding mechanism. The maximum length of text which can be placed in a 
Maxicode symbol depends on the type of characters used in the text.

Example maximum data lengths are given in the table below:

-----------------------------------------------------------------------------
Mode  |  Maximum Data Lenth   |  Maximum Data Length  |  Number of Error
      |  for Capital Letters  |  for Numeric Digits   |  Correction Codewords
-----------------------------------------------------------------------------
2*    |  84                   |  126                  |  50
3*    |  84                   |  126                  |  50
4     |  93                   |  135                  |  50
5     |  77                   |  110                  |  66
6     |  93                   |  135                  |  50
-----------------------------------------------------------------------------
* - secondary only

6.6.5 Aztec Code (ISO 24778)
----------------------------
Invented by Andrew Longacre at Welch Allyn Inc in 1995 the Aztec Code symbol is 
a matrix symbol with a distinctive bulls-eye finder pattern. Zint can generate 
Compact Aztec Code (sometimes called Small Aztec Code) as well as "full-range" 
Aztec Code symbols and by default will automatically select symbol type and 
size dependent on the length of the data to be encoded. Error correction 
codewords will normally be generated to fill at least 23% of the symbol. Two 
options are available to change this behaviour:

The size of the symbol can be specified using the --ver= option or setting 
option_2 to a value between 1 and 36 according to the following table. The 
symbols marked with an asterisk (*) in the table below are "compact" symbols, 
meaning they have a smaller bulls-eye pattern at the centre of the symbol. 

---------------------
Input  |  Symbol Size
---------------------
1      |  15 x 15*
2      |  19 x 19*
3      |  23 x 23*
4      |  27 x 27*
5      |  19 x 19
6      |  23 x 23
7      |  27 x 27
8      |  31 x 31
9      |  37 x 37
10     |  41 x 41
11     |  45 x 45
12     |  49 x 49
13     |  53 x 53
14     |  57 x 57
15     |  61 x 61
16     |  67 x 67
17     |  71 x 71
18     |  75 x 75
19     |  79 x 79
20     |  83 x 83
21     |  87 x 87
22     |  91 x 91
23     |  95 x 95
24     |  101 x 101
25     |  105 x 105
26     |  109 x 109
28     |  113 x 113
28     |  117 x 117
29     |  121 x 121
30     |  125 x 125
31     |  131 x 131
32     |  135 x 135
33     |  139 x 139
34     |  143 x 143
35     |  147 x 147
36     |  151 x 151
---------------------

Note that in symbols which have a specified size the amount of error correction 
is dependent on the length of the data input and Zint will allow error 
correction capacities as low as 3 codewords.

Alternatively the amount of error correction data can be specified by use of 
the --mode= option or by setting option_1 to a value from the following table: 

----------------------------------
Mode  |  Error Correction Capacity
----------------------------------
1     |  >10% + 3 codewords
2     |  >23% + 3 codewords
3     |  >36% + 3 codewords
4     |  >50% + 3 codewords
----------------------------------

It is not possible to select both symbol size and error correction capacity for 
the same symbol. If both options are selected then the error correction 
capacity selection will be ignored. 

Aztec Code supports ECI encoding and can encode up to a maximum length of 
approximately 3823 numeric or 3067 alphabetic characters or 1914 bytes of data. 
A separate symbology ID can be used to encode Health Industry Barcode (HIBC) 
data which adds a leading '+' character and a modulo-49 check digit to the 
encoded data.

6.6.6 Aztec Runes
-----------------
A truncated version of compact Aztec Code for encoding whole integers between 0 
and 255. Includes Reed-Solomon error correction. As defined in ISO/IEC 24778 
Annex A. 

6.6.7 Code One
--------------
A matrix symbology developed by Ted Williams in 1992 which encodes data in a 
way similar to Data Matrix ECC200. Code One is able to encode the Latin-1 
character set or GS1 data. There are two types of Code One symbol - variable 
height symbols which are roughly square (versions A thought to H) and 
fixed-height versions (version S and T). These can be selected by using --vers= 
or setting option_2 as shown in the table below: 

--------------------------------------------------------------------
Input  |  Version  |  Size        |  Numeric        |  Alphanumeric
       |           |              |  Data Capacity  |  Data Capacity
--------------------------------------------------------------------
1      |  A        |  16 x 18     |  22             |  13
2      |  B        |  22 x 22     |  44             |  27
3      |  C        |  28 x 28     |  104            |  64
4      |  D        |  40 x 42     |  217            |  135
5      |  E        |  52 x 54     |  435            |  271
6      |  F        |  70 x 76     |  886            |  553
7      |  G        |  104 x 98    |  1755           |  1096
8      |  H        |  148 x 134   |  3550           |  2218
9      |  S        |  8X height   |  18             |  N/A
10     |  T        |  16X height  |  90             |  55
--------------------------------------------------------------------

Version S symbols can only encode numeric data. The width of version S and 
version T symbols is determined by the length of the input data. 

6.6.8 Grid Matrix
-----------------
By default Grid Matrix supports encoding in Latin-1 and Chinese characters 
within the GB 2312 standard set to be encoded in a checkerboard pattern. Input 
should be entered as Unicode (UTF-8) with conversion to GB 2312 being carried 
out automatically by Zint. The symbology also supports the ECI mechanism. The 
size of the symbol and the error correction capacity can be specified. If you 
specify both of these values then Zint will make a 'best-fit' attempt to 
satisfy  both conditions. The symbol size can be specified using the --ver=
option or by setting option_2, and the error correction capacity can be
specified by using the --security= option or by setting option_1 according to
the following tables: 

---------------------
Input  |  Symbol Size
---------------------
1      |  18 x 18
2      |  30 x 30
3      |  42 x 42
4      |  54 x 54
5      |  66 x 66
6      |  78 x 78
7      |  90 x 90
8      |  102 x 102
9      |  114 x 114
10     |  126 x 126
11     |  138 x 138
12     |  150 x 150
13     |  162 x 162
---------------------

----------------------------------
Mode  |  Error Correction Capacity
----------------------------------
1     |  Approximately 10%
2     |  Approximately 20%
3     |  Approximately 30%
4     |  Approximately 40%
5     |  Approximately 50%
----------------------------------

6.6.9 DotCode
-------------
DotCode uses a grid of dots in a rectangular formation to encode characters up 
to a maximum of approximately 450 characters (or 900 numeric digits). The 
symbology supports ECI encoding and GS-1 data encoding. By default Zint will 
produce a symbol which is approximately square, however the width of the symbol 
can be adjusted by using the --cols= option or by setting option_2. Outputting 
DotCode to raster images (PNG, GIF, BMP, PCX) will require setting the scale of 
the image to a larger value than the default (e.g. approx 10) for the dots to 
be plotted correctly. Approximately 33% of the resulting symbol is comprised of 
error correction codewords.

6.6.10 Han Xin Code
-------------------
Also known as Chinese Sensible Code, Han Xin is a symbology which is still 
under 
development, so it is recommended it should not yet be used for a production 
environment. The symbology is capable of encoding characters in the GB18030 
character set (up to 4-byte characters) and is also able to support the ECI 
mechanism. Han Xin does not support the encoding of GS-1 data.

The size of the symbol can be specified using the --ver= option or setting 
option_2 to a value between 1 and 84 according to the following table.

---------------------
Input  |  Symbol Size
---------------------
1      |  23 x 23
2      |  25 x 25
3      |  27 x 27
4      |  29 x 29
5      |  31 x 31
6      |  33 x 33
7      |  35 x 35
8      |  37 x 37
9      |  39 x 39
10     |  41 x 41
11     |  43 x 43
12     |  45 x 45
13     |  47 x 47
14     |  49 x 49
15     |  51 x 51
16     |  53 x 53
17     |  55 x 55
18     |  57 x 57
19     |  59 x 59
20     |  61 x 61
21     |  63 x 63
22     |  65 x 65
23     |  67 x 67
24     |  69 x 69
25     |  71 x 71
26     |  73 x 73
28     |  75 x 75
28     |  77 x 77
29     |  79 x 79
30     |  81 x 81
31     |  83 x 83
32     |  85 x 85
33     |  87 x 87
34     |  89 x 89
35     |  91 x 91
36     |  93 x 93
37     |  95 x 95
38     |  97 x 97
39     |  99 x 99
40     |  101 x 101
41     |  103 x 103
42     |  105 x 105
43     |  107 x 107
44     |  109 x 109
45     |  111 x 111
46     |  113 x 113
47     |  115 x 115
48     |  117 x 117
49     |  119 x 119
50     |  121 x 121
51     |  123 x 123
52     |  125 x 125
53     |  127 x 127
54     |  129 x 129
55     |  131 x 131
56     |  133 x 133
57     |  135 x 135
58     |  137 x 137
59     |  139 x 139
60     |  141 x 141
61     |  143 x 143
62     |  145 x 145
63     |  147 x 147
64     |  149 x 149
65     |  151 x 151
66     |  153 x 153
67     |  155 x 155
68     |  157 x 157
69     |  159 x 159
70     |  161 x 161
71     |  163 x 163
72     |  165 x 165
73     |  167 x 167
74     |  169 x 169
75     |  171 x 171
76     |  173 x 173
77     |  175 x 175
78     |  177 x 177
79     |  179 x 179
80     |  181 x 181
81     |  183 x 183
82     |  185 x 185
83     |  187 x 187
84     |  189 x 189
---------------------

There are four levels of error correction capacity available for Han Xin Code 
which can be set by using the --mode= option or by setting option_1 to a value 
from the following table:

--------------------------
Mode  |  Recovery Capacity
--------------------------
1     |  Approx 8%
2     |  Approx 15%
3     |  Approx 23%
4     |  Approx 30%
--------------------------

It is not possible to select both symbol size and error correction capacity for 
the same symbol. If both options are selected then the error correction 
capacity selection will be ignored.

6.7 Other Barcode-Like Markings
-------------------------------
6.7.1. Facing Identification Mark (FIM)
---------------------------------------
Used by the United States Postal Service (USPS), the FIM symbology is used to 
assist automated mail processing. There are only 4 valid symbols which can be 
generated using the characters A-D as shown in the table below. 

----------------------------------------------------------------------------
Code Letter  |  Usage
----------------------------------------------------------------------------
A            |  Used for courtesy reply mail and metered reply mail with a 
             |     pre-printed PostNet symbol. 
B            |  Used for business reply mail without a pre-printed zip code.
C            |  Used for business reply mail with a pre-printed zip code.
D            |  Used for Information Based Indicia (IBI) postage. 
----------------------------------------------------------------------------

6.7.2 Flattermarken
-------------------
Used for the recognition of page sequences in print-shops, the Flattermarken is 
not a true barcode symbol and requires precise knowledge of the position of the 
mark on the page. The Flattermarken system can encode any length numeric data 
and does not include a check digit. 

6.7.3 DAFT Code
---------------
This is a method for creating 4-state codes where the data encoding is provided 
by an external program. Input data should consist of the letters 'D', 'A', 'F' 
and 'T' where these refer to descender, ascender, full (ascender and descender) 
and tracker (neither ascender nor descender) respectively. All other characters 
are ignored. 

7. Legal and Version Information
================================
7.1 License
-----------
Zint, libzint and Zint Barcode Studio are Copyright © 2016 Robin Stuart. All 
historical versions are distributed under the GNU General Public License 
version 3 or later. Version 2.5 is released under a dual license: the encoding 
library is released under the BSD license whereas the GUI, Zint Barcode Studio, 
is released under the GNU General Public License version 3 or later.

Telepen is a trademark of SB Electronic Systems Ltd.

QR Code is a registered trademark of Denso Wave Incorporated.

Microsoft, Windows and the Windows logo are either registered trademarks or 
trademarks of Microsoft Corporation in the United States and/or other countries.

Linux is the registered trademark of Linus Torvalds in the U.S. and other
countries.

Zint.org.uk website design and hosting provided by Robert Elliott.

7.2 Patent Issues
-----------------
All of the code in Zint is developed using information in the public domain, 
usually freely available on the Internet. Some of the techniques used may be 
subject to patents and other intellectual property legislation. It is my belief 
that any patents involved in the technology underlying symbologies utilised by 
Zint are 'unadopted', that is the holder does not object to their methods being 
used.

Any methods patented or owned by third parties or trademarks or registered 
trademarks used within Zint or in this document are and remain the property of 
their respective owners and do not indicate endorsement or affiliation with 
those owners, companies or organisations. 

7.3 Version Information
-----------------------
v0.1 - (as Zebar) Draws UPC-A. UPC-E, EAN-8, EAN-13, Interlaced 2 of 5, 
Codabar, Code 39, Extended Code 39 and Code 93 barcodes and Add-on codes EAN-2 
and EAN-5 without parity. 13/11/2006

v0.2 - Added Code 128 (which is now the default), Code 11, Code 2 of 5, Add-on 
codes EAN-2 and EAN-5 parity and MSI/Plessey without check digit. 12/12/2006

v0.3 - Added MSI/Plessey Mod 10 check and 2 x Mod 10 check options, Telepen 
ASCII and Telepen numeric, Postnet, RM4SCC. Code has been tidied up quite a 
bit. Bind option added. 30/12/2006

v0.4 - Added barcode stacking (now stacks up to 16 barcodes) and Code16k 
(stub). 15/1/2007

v0.5 - Added Australia Post 4-State Barcodes and Pharmacode (1 and 2 track). 
4-state codes now draw with correct height/width ratio. 28/2/2007

v0.6 - Added Plessey and some derivative codes (EAN-128, Code 128 subset B, 
Auspost Reply, Auspost Routing, Auspost Redirect, ITF-14). Tidied up code 
again: separated symbologies into more files and put all lookup tables into 
arrays (much reducing the amount of code, especially for Code 39e and Code 93). 
Errors now output to stderr. Added proper input verification. Distribution now 
packs with HTML pages instead of separate README. Outputs to PNG. Outputs 
colour. User variable whitespace and border width. Box option. Fixed EAN add-on 
bug. Added whitespace and height options. Project name changed to Zint to avoid 
conflict with extant trade name. Added escape character input. 1/4/2007

v1.0 - Corrected problem with escape character codes. Supports PDF417. This 
completes the list of features I originally wanted (plus a few more), hence 
skip to version 1.0. 20/4/2007

v1.1 - Added more derivatives (Code 2 of 5 Matrix, IATA and Data Logic, 
Truncated PDF417, Deutsche Post Leitcode and Identcode, Pharmazentralnummer, 
Planet) and Flattermarken. Tidied up 2 of 5 code. 26/4/2007

v1.2 - Supports Data Matrix ECC200 (by absorption of IEC16022 code by Stefan 
Schmidt et al). Added reverse colours, FIM, MSI/Plessey Modulo 11 and Modulo 
11/10. Corrected Code 16k check digit calculation. 28/5/2007

v1.3 - Supports USPS OneCode and LOGMARS. Brought all usage information into 
one User Manual document. 13/6/2007

v1.4 - Added NVE-18 support. Corrected some problems with compilation and input 
verification. Command line option handling now uses getopt(), and all the 
switches have changed. Added –font option. 20/6/2007

v1.5 - Pulled everything together to make an API. Corrected errors with EAN-13, 
PDF417 and LOGMARS. Added EPS output. Added QR Code support using libqrencode. 
Corrected ISBN verification error. Re-compiled documentation in HTML form. Put 
in place proper error handling routines. --font option removed. Encoding is now 
done with a restructured zint_symbol structure. Added make install option and 
optional QR Code support to Makefile. Corrected minor problem with 4-State 
Codes. Restructured code into fewer source code files. Added MicroPDF417 
support. 12/8/2007

v1.5.1 - Added formatting code to EPS output of EAN and UPC symbols according 
to EN 797:1996. Checked against and, where appropriate, altered or corrected to 
comply with ISO 16388 and ISO 15417 including Latin-1 support. Altered default 
image settings, added automatic ITF border. Corrected error with USPS OneCode. 
Tidied up Code 39 quite a bit, added Mod 43 options. 3/9/2007

v1.5.2 - Added extended ASCII support to Code 16k. Corrected Code 128 error. 
Added Maxicode support by integrating code by John Lien. 26/9/2007

v1.5.3 - Made huge corrections to Maxicode support by removing and re-writing 
much of John's code. Maxicode now supports extended ASCII and modes 4, 5 and 6. 
10/10/2007

v1.5.4 - Added GS1 DataBar (Reduced Space Symbology) support. 26/11/2007

v1.5.5 - Added composite symbology support. Corrected errors with GS1-128 and

PDF417/MicroPDF417 byte processing. Transferred licence to GPL version 3. 
9/3/2008

v1.6 - Data Matrix ECC200, Maxicode and Australia Post now use common 
Reed-Solomon functions – this also fixes a bug in Maxicode error correction and 
replaces the last of the Lien code. Added PNG output for Maxicode symbols. 
Removed some useless code. Updated QR support for libqrencode v2.0.0. 22/4/2008

v1.6.1 - Major restructuring of PNG generating code: Now draws UPCA and EAN 
symbols properly and puts human readable text into the image. Also corrected 
some nasty 'never ending loop' bugs in Code 128 and check digit bugs in PostNet 
and Planet. 8/7/2008

v1.6.2 - Added KIX Code support and PNG image rotation. Corrected a bug 
affecting extended ASCII support in Code 128 and Code 16k. 28/7/2008.

v2.0 beta - Added support for Aztec Code, Codablock-F, Code 32, EAN-14 and DAFT 
Code. Rearranged symbology numbers to match Tbarcode v8. Corrected a never 
ending loop bug in EAN-128. 29/9/2008

v2.0 beta r2 - Many corrections and bugfixes. (Code 11, Code 128, EAN-128, 
Aztec Code, Codablock-F, Code 16k, Postnet, PLANET, NVE-18, PZN, Data Matrix 
ECC200, Maxicode and QR Code)

v2.0 - Made corrections to Aztec Code and tested output with bcTester. Added 
Aztec Runes, Micro QR Code and Data Matrix ECC200 ECC 000-140. Updated e-mail 
information. 18/11/2008

v2.1 - Reinstated Korea Post barcodes, harmonised bind and box options, moved 
Unicode handling into backend and added input_mode option, added size options 
to Data Matrix ECC200, added NULL character handling for Codablock-F, Code 128, 
Code 16k, Extended Code 39, Code 93, Telepen, Maxicode, Data Matrix ECC200 ECC 
200, PDF417 and MicroPDF417. Added GS1 support for Code 16k, Codablock-F and 
Aztec Code. Added scale and direct to stdout options. Rebult Data Matrix ECC200 
ECC 200 encoding algorithms to support NULL encoding and GS1 data encoding. 
31/1/2009

v2.1.1 - Minor Data Matrix ECC200 bugfix and added HIBC options. 10/2/2009

v2.1.2 - Added SVG output option. Improved Japanese character support including 
Unicode > Shift-JIS capability. Bugfixes for Data Matrix ECC200 (missing 
characters at end of string) and Codablock-F (K1/K2 check digit and row 
indicators above row 6). 1/3/2009

v2.1.3 - Many improvements to the QZint GUI which is now renamed "Zint Barcode 
Studio 0.2". Added Japanese Postal Barcode, Code 49 and Channel Code and made 
corrections to Data Matrix ECC200 (Binary mode data compression terminates too 
soon), Aztec Code (Bug when automatically resizing after removing "all 0" and 
"all 1" codewords) and Code 128 (Extended ASCII characters become corrupt). 
19/5/2009

v2.1.4 - Many stability improvements including removal of buffer overruns in 
Code 39, LOGMARS, PZN, Aztec Code and Composite CC-A. Addition of files for 
compiling on MS Windows platform - tested successfully on XP and Vista. 
19/6/2009

v2.2 - Added Code One and GS1 support in Code 49. Changed GUI binary name to 
zint-qt and brought GUI up to version 1.0. Made some minor bugfixes to Code 39, 
ITF-14, Aztec Code, Code 128 and Code 16K. Added 'rest' button to GUI. Included 
.spec file from Radist. 18/7/2009

v2.2.1 - Data encoding bugfixes for Aztec Code, Data Matrix ECC200, USPS One 
Code and PDF417. Symbol plotting bugfixes for MicroPDF417 and 2D components of 
composite symbols. Text formatting bugfix for Qt renderer and a couple of 
compiler fixes for MSVC PNG image output. 6/8/2009

v2.2.2 - A beta release previewing the new API structure. Better NULL character 
support with "nullchar" value removed. Added loading from file and sequence 
dialogs in Barcode Studio. 29/9/2009

v2.3 - Fixed problems with Micro QR Code and rebuilt QR Code support removing 
dependence on libqrencode. Improved Kanji character support for QR Code and 
Micro QR Code which now auto-detects and automatically converts to Shift-JIS. 
Added Grid Matrix symbology with Kanji character support and automatic 
conversion to GB 2312. Removed no_qr compile option. Advanced Barcode Studio 
version number to match library version number. 23/11/2009

v2.3.1 - Removed Codablock-F. Redesigned scale function so that human readable 
text and Maxicode symbols can be scaled consistently. Corrected encoding bugs 
with Code 128/Code 16k and Data Matrix ECC200 ECC 050. Added --notext option to 
CLI. 7/3/2010

v2.3.2 - Corrected many bugs in GS1 DataBar Extended thanks to the careful 
study of the code by Pablo Orduña at the PIRAmIDE project. Similarly corrected 
some bugs in Maxicode thanks to Monica Swanson at Source Technologies. Also 
minor bugfixes for ISBN and Aztec Code, and added some small features like a 
--square option in the CLI. 29/5/2010

v2.4 - Built extensions to the API for integrating with glabels with thanks to 
Sam Lown and Jim Evins. Added code optimisation and input from stdin thanks to 
Ismael Luceno. Reinstated escape character input. Simplification of Barcode 
Studio. 13/9/2010

v2.4.1 & 2.4.2 – A whole host of bugfixes including correction of ECC routines 
for Code-1 and addition of batch processing at the command line. 19/4/2011 &
4/5/2011

v2.4.3 - Includes minor bugfixes 16/5/2011

v2.5 – Support for DotCode and Han Xin code. ECI code processing. Output to 
BMP, GIF and PCX. Added bold text option. Many minor bugfixes and improvements. 
(Due for release November 2016).

7.4 Sources of Information
--------------------------
Below is a list of some of the sources used in rough chronological order:

Nick Johnson's Barcode Specifications
Bar Code 1 Specification Source Page
SB Electronic Systems Telepen website
Pharmacode specifications from Laetus
Morovia RM4SCC specification
Austalia Post's 'A Guide to Printing the 4-State Barcode' and bcsample source 
   code
Plessey algorithm from GNU-Barcode v0.98 by Leonid A. Broukhis
GS1 General Specifications v 8.0 Issue 2
PNG: The Definitive Guide and wpng source code by Greg Reolofs
PDF417 specification and pdf417 source code by Grand Zebu
Barcode Reference, TBarCode/X User Documentation and TBarCode/X demonstration 
   program from Tec-It
IEC16022 source code by Stefan Schmidt et al
United States Postal Service Specification USPS-B-3200
Adobe Systems Incorporated Encapsulated PostScript File Format Specification
BSI Online Library
Libdmtx Data Matrix ECC200 decoding library

7.5 Standard Compliance
-----------------------
Zint was developed to provide compliance with the following British and 
international standards: 

> BS EN 797:1996 Bar coding - Symbology specifications - 'EAN/UPC' 
> BS EN 798:1996 Bar coding - Symbology specifications - 'Codabar' 
> ISO/IEC 12323:2005 AIDC technologies - Symbology specifications - Code 16K 
> ISO/IEC 15417:2007 Information technology - Automatic identification and data 
     capture techniques - Code 128 bar code symbology specification 
> ISO/IEC 15438:20062015 Information technology - Automatic identification and 
     data capture techniques - PDF417 bar code symbology specification 
> ISO/IEC 16022:2006 Information technology - Automatic identification and data 
     capture techniques - Data Matrix ECC200 bar code symbology specification 
> ISO/IEC 16023:2000 Information technology - International symbology 
     specification – Maxicode 
> ISO/IEC 16388:2007 Information technology - Automatic identification and data 
     capture techniques - Code 39 bar code symbology specification 
> ISO/IEC 18004:2015 Information technology - Automatic identification and data 
     capture techniques - QR Code bar code symbology specification 
> ISO/IEC 24723:2010 Information technology - Automatic identification and data 
     capture techniques - GS1 Composite bar code symbology specification 
> ISO/IEC 24724:2011 Information technology - Automatic identification and data 
     capture techniques - GS1 DataBar bar code symbology specification 
> ISO/IEC 24728:2006 Information technology - Automatic identification and data 
     capture techniques - MicroPDF417 bar code symbology specification 
> ISO/IEC 24778:2008 Information technology - Automatic identification and data 
     capture techniques - Aztec Code bar code symbology specification 
> Uniform Symbology Specification Code One (AIM Inc., 1994) 
> ANSI/AIM BC12-1998 - Uniform Symbology Specification Channel Code 
> ANSI/AIM BC6-2000 - Uniform Symbology Specification Code 49 
> ANSI/HIBC 2.3-2009 - The Health Industry Bar Code (HIBC) Supplier Labeling 
     Standard 
> AIM ISS-X-24 - Uniform Symbology Specification Codablock F
> AIMD013 (v 1.34a) – Information technology – Automaic identification and data 
     capture techniques – Bar code symbology specification – DotCode (Revised 
     19th Feb 2009)
> AIMD014 (v 1.63) - Information technology, Automatic identification and data 
     capture techniques - Bar code symbology specification - Grid Matrix 
     (Released 9th Dec 2008) 
> AIMD-015:2010 (v 0.8) – DRAFT Bar code symbology specification – Han Xin Code 
     (Revised 25th March 2010)
> GS1 General Specifications Version 8.0 
> AIM ITS/04-001 International Technical Standard – Extended Channel 
     Interpretations Part 1: Identification Schemes and Protocol (Released 24th 
     May 2004)
> AIM ITS/04-023 International Technical Standard – Extended Channel 
     Interpretations Part 3: Register (Released 15th July 2004)
     
A. Character Encoding
=====================
This section is intended as a quick reference to the character sets used by 
Zint. All symbologies use standard ASCII input as shown in section A.1, but 
some support extended character support as shown in the subsequent section.

A.1 ASCII Standard
------------------
The ubiquitous ASCII standard is well known to most computer users. It's 
reproduced here for reference.

-------------------------------------------------------------
Hex |  0     |  1    |  2      |  3  |  4  |  5  |  6  |  7
-------------------------------------------------------------
0   |  NULL  |  DLE  |  SPACE  |  0  |  @  |  P  |  `  |  p
1   |  SOH   |  DC1  |  !      |  1  |  A  |  Q  |  a  |  q
2   |  STX   |  DC2  |  "      |  2  |  B  |  R  |  b  |  r
3   |  ETX   |  DC3  |  #      |  3  |  C  |  S  |  c  |  s
4   |  EOT   |  DC4  |  $      |  4  |  D  |  T  |  d  |  t
5   |  ENQ   |  NAK  |  %      |  5  |  E  |  U  |  e  |  u
6   |  ACK   |  SYN  |  &      |  6  |  F  |  V  |  f  |  v
7   |  BEL   |  ETB  |  '      |  7  |  G  |  W  |  g  |  w
8   |  BS    |  CAN  |  (      |  8  |  H  |  X  |  h  |  x
9   |  TAB   |  EM   |  )      |  9  |  I  |  Y  |  i  |  y
A   |  LF    |  SUB  |  *      |  :  |  J  |  Z  |  j  |  z
B   |  VT    |  ESC  |  +      |  ;  |  K  |  [  |  k  |  {
C   |  FF    |  FS   |  ,      |  <  |  L  |  \  |  l  |  |
D   |  CR    |  GS   |  -      |  =  |  M  |  ]  |  m  |  }
E   |  SO    |  RS   |  .      |  >  |  N  |  ^  |  n  |  ~
F   |  SI    |  US   |  /      |  ?  |  O  |  _  |  o  |  DEL
-------------------------------------------------------------

A.2 Latin Alphabet No 1 (ISO 8859-1)
------------------------------------
A common extension to the ASCII standard, Latin-1 is used to expand the range 
of Code 128, PDF417 and other symbols. Input strings should be in Unicode 
format 

------------------------------------------------------
Hex |  8  |  9  |  A      |  B  |  C  |  D  |  E  |  F
------------------------------------------------------
0   |     |     |  NBSP   |  °  |  À  |  Ð  |  à  |  ð
1   |     |     |  ¡      |  ±  |  Á  |  Ñ  |  á  |  ñ
2   |     |     |  ¢      |  ²  |  Â  |  Ò  |  â  |  ò
3   |     |     |  £      |  ³  |  Ã  |  Ó  |  ã  |  ó
4   |     |     |  ¤      |  ´  |  Ä  |  Ô  |  ä  |  ô
5   |     |     |  ¥      |  μ  |  Å  |  Õ  |  å  |  õ
6   |     |     |  ¦      |  ¶  |  Æ  |  Ö  |  æ  |  ö
7   |     |     |  §      |  ·  |  Ç  |  ×  |  ç  |  ÷
8   |     |     |  ¨      |  ¸  |  È  |  Ø  |  è  |  ø
9   |     |     |  ©      |  ¹  |  É  |  Ù  |  é  |  ù
A   |     |     |  ª      |  º  |  Ê  |  Ú  |  ê  |  ú
B   |     |     |  «      |  »  |  Ë  |  Û  |  ë  |  û
C   |     |     |  ¬      |  ¼  |  Ì  |  Ü  |  ì  |  ü
D   |     |     |  SHY    |  ½  |  Í  |  Ý  |  í  |  ý
E   |     |     |  ®      |  ¾  |  Î  |  Þ  |  î  |  þ
F   |     |     |  ¯      |  ¿  |  Ï  |  ß  |  î  |  ÿ
------------------------------------------------------

B. Three Digit Country Codes (ISO 3166)
---------------------------------------
Below are some of the three digit country codes (in right-hand column) as 
determined by ISO 3166 for use with Maxicode symbols. 

Country                                         A 2     A 3     Number
----------------------------------------------------------------------
AALAND ISLANDS                                  AX      ALA     248
AFGHANISTAN                                     AF      AFG     004
ALBANIA                                         AL      ALB     008
ALGERIA                                         DZ      DZA     012
AMERICAN SAMOA                                  AS      ASM     016
ANDORRA                                         AD      AND     020
ANGOLA                                          AO      AGO     024
ANGUILLA                                        AI      AIA     660
ANTARCTICA                                      AQ      ATA     010
ANTIGUA AND BARBUDA                             AG      ATG     028
ARGENTINA                                       AR      ARG     032
ARMENIA                                         AM      ARM     051  
ARUBA                                           AW      ABW     533
AUSTRALIA                                       AU      AUS     036
AUSTRIA                                         AT      AUT     040
AZERBAIJAN                                      AZ      AZE     031  
BAHAMAS                                         BS      BHS     044
BAHRAIN                                         BH      BHR     048
BANGLADESH                                      BD      BGD     050
BARBADOS                                        BB      BRB     052
BELARUS                                         BY      BLR     112  
BELGIUM                                         BE      BEL     056
BELIZE                                          BZ      BLZ     084
BENIN                                           BJ      BEN     204
BERMUDA                                         BM      BMU     060
BHUTAN                                          BT      BTN     064
BOLIVIA                                         BO      BOL     068
BOSNIA AND HERZEGOWINA                          BA      BIH     070
BOTSWANA                                        BW      BWA     072
BOUVET ISLAND                                   BV      BVT     074
BRAZIL                                          BR      BRA     076
BRITISH INDIAN OCEAN TERRITORY                  IO      IOT     086
BRUNEI DARUSSALAM                               BN      BRN     096
BULGARIA                                        BG      BGR     100
BURKINA FASO                                    BF      BFA     854
BURUNDI                                         BI      BDI     108
CAMBODIA                                        KH      KHM     116
CAMEROON                                        CM      CMR     120
CANADA                                          CA      CAN     124
CAPE VERDE                                      CV      CPV     132
CAYMAN ISLANDS                                  KY      CYM     136
CENTRAL AFRICAN REPUBLIC                        CF      CAF     140
CHAD                                            TD      TCD     148
CHILE                                           CL      CHL     152
CHINA                                           CN      CHN     156
CHRISTMAS ISLAND                                CX      CXR     162
COCOS (KEELING) ISLANDS                         CC      CCK     166
COLOMBIA                                        CO      COL     170
COMOROS                                         KM      COM     174
CONGO, Democratic Republic of (was Zaire)       CD      COD     180
CONGO, Republic of                              CG      COG     178
COOK ISLANDS                                    CK      COK     184
COSTA RICA                                      CR      CRI     188
COTE D'IVOIRE                                   CI      CIV     384
CROATIA (local name: Hrvatska)                  HR      HRV     191      
CUBA                                            CU      CUB     192
CYPRUS                                          CY      CYP     196
CZECH REPUBLIC                                  CZ      CZE     203  
DENMARK                                         DK      DNK     208
DJIBOUTI                                        DJ      DJI     262
DOMINICA                                        DM      DMA     212
DOMINICAN REPUBLIC                              DO      DOM     214
ECUADOR                                         EC      ECU     218
EGYPT                                           EG      EGY     818
EL SALVADOR                                     SV      SLV     222
EQUATORIAL GUINEA                               GQ      GNQ     226
ERITREA                                         ER      ERI     232
ESTONIA                                         EE      EST     233  
ETHIOPIA                                        ET      ETH     231
FALKLAND ISLANDS (MALVINAS)                     FK      FLK     238
FAROE ISLANDS                                   FO      FRO     234
FIJI                                            FJ      FJI     242
FINLAND                                         FI      FIN     246
FRANCE                                          FR      FRA     250
FRENCH GUIANA                                   GF      GUF     254
FRENCH POLYNESIA                                PF      PYF     258
FRENCH SOUTHERN TERRITORIES                     TF      ATF     260
GABON                                           GA      GAB     266
GAMBIA                                          GM      GMB     270
GEORGIA                                         GE      GEO     268  
GERMANY                                         DE      DEU     276
GHANA                                           GH      GHA     288
GIBRALTAR                                       GI      GIB     292
GREECE                                          GR      GRC     300
GREENLAND                                       GL      GRL     304
GRENADA                                         GD      GRD     308
GUADELOUPE                                      GP      GLP     312
GUAM                                            GU      GUM     316
GUATEMALA                                       GT      GTM     320
GUINEA                                          GN      GIN     324
GUINEA-BISSAU                                   GW      GNB     624
GUYANA                                          GY      GUY     328
HAITI                                           HT      HTI     332
HEARD AND MC DONALD ISLANDS                     HM      HMD     334
HONDURAS                                        HN      HND     340
HONG KONG                                       HK      HKG     344
HUNGARY                                         HU      HUN     348
ICELAND                                         IS      ISL     352
INDIA                                           IN      IND     356
INDONESIA                                       ID      IDN     360
IRAN (ISLAMIC REPUBLIC OF)                      IR      IRN     364
IRAQ                                            IQ      IRQ     368
IRELAND                                         IE      IRL     372
ISRAEL                                          IL      ISR     376
ITALY                                           IT      ITA     380
JAMAICA                                         JM      JAM     388
JAPAN                                           JP      JPN     392
JORDAN                                          JO      JOR     400
KAZAKHSTAN                                      KZ      KAZ     398  
KENYA                                           KE      KEN     404
KIRIBATI                                        KI      KIR     296
KOREA, DEMOCRATIC PEOPLE'S REPUBLIC OF          KP      PRK     408
KOREA, REPUBLIC OF                              KR      KOR     410
KUWAIT                                          KW      KWT     414
KYRGYZSTAN                                      KG      KGZ     417  
LAO PEOPLE'S DEMOCRATIC REPUBLIC                LA      LAO     418
LATVIA                                          LV      LVA     428  
LEBANON                                         LB      LBN     422
LESOTHO                                         LS      LSO     426
LIBERIA                                         LR      LBR     430
LIBYAN ARAB JAMAHIRIYA                          LY      LBY     434
LIECHTENSTEIN                                   LI      LIE     438
LITHUANIA                                       LT      LTU     440  
LUXEMBOURG                                      LU      LUX     442
MACAU                                           MO      MAC     446
MACEDONIA, THE FORMER YUGOSLAV REPUBLIC OF      MK      MKD     807 
MADAGASCAR                                      MG      MDG     450
MALAWI                                          MW      MWI     454
MALAYSIA                                        MY      MYS     458
MALDIVES                                        MV      MDV     462
MALI                                            ML      MLI     466
MALTA                                           MT      MLT     470
MARSHALL ISLANDS                                MH      MHL     584
MARTINIQUE                                      MQ      MTQ     474
MAURITANIA                                      MR      MRT     478
MAURITIUS                                       MU      MUS     480
MAYOTTE                                         YT      MYT     175  
MEXICO                                          MX      MEX     484
MICRONESIA, FEDERATED STATES OF                 FM      FSM     583
MOLDOVA, REPUBLIC OF                            MD      MDA     498  
MONACO                                          MC      MCO     492
MONGOLIA                                        MN      MNG     496
MONTSERRAT                                      MS      MSR     500
MOROCCO                                         MA      MAR     504
MOZAMBIQUE                                      MZ      MOZ     508
MYANMAR                                         MM      MMR     104
NAMIBIA                                         NA      NAM     516
NAURU                                           NR      NRU     520
NEPAL                                           NP      NPL     524
NETHERLANDS                                     NL      NLD     528
NETHERLANDS ANTILLES                            AN      ANT     530
NEW CALEDONIA                                   NC      NCL     540
NEW ZEALAND                                     NZ      NZL     554
NICARAGUA                                       NI      NIC     558
NIGER                                           NE      NER     562
NIGERIA                                         NG      NGA     566
NIUE                                            NU      NIU     570
NORFOLK ISLAND                                  NF      NFK     574
NORTHERN MARIANA ISLANDS                        MP      MNP     580
NORWAY                                          NO      NOR     578
OMAN                                            OM      OMN     512
PAKISTAN                                        PK      PAK     586
PALAU                                           PW      PLW     585
PALESTINIAN TERRITORY, Occupied                 PS      PSE     275
PANAMA                                          PA      PAN     591
PAPUA NEW GUINEA                                PG      PNG     598
PARAGUAY                                        PY      PRY     600
PERU                                            PE      PER     604
PHILIPPINES                                     PH      PHL     608
PITCAIRN                                        PN      PCN     612
POLAND                                          PL      POL     616
PORTUGAL                                        PT      PRT     620
PUERTO RICO                                     PR      PRI     630
QATAR                                           QA      QAT     634
REUNION                                         RE      REU     638
ROMANIA                                         RO      ROU     642
RUSSIAN FEDERATION                              RU      RUS     643
RWANDA                                          RW      RWA     646
SAINT HELENA                                    SH      SHN     654
SAINT KITTS AND NEVIS                           KN      KNA     659
SAINT LUCIA                                     LC      LCA     662
SAINT PIERRE AND MIQUELON                       PM      SPM     666
SAINT VINCENT AND THE GRENADINES                VC      VCT     670
SAMOA                                           WS      WSM     882
SAN MARINO                                      SM      SMR     674
SAO TOME AND PRINCIPE                           ST      STP     678
SAUDI ARABIA                                    SA      SAU     682
SENEGAL                                         SN      SEN     686
SERBIA AND MONTENEGRO                           CS      SCG     891
SEYCHELLES                                      SC      SYC     690
SIERRA LEONE                                    SL      SLE     694
SINGAPORE                                       SG      SGP     702
SLOVAKIA                                        SK      SVK     703  
SLOVENIA                                        SI      SVN     705  
SOLOMON ISLANDS                                 SB      SLB     090
SOMALIA                                         SO      SOM     706
SOUTH AFRICA                                    ZA      ZAF     710
SOUTH GEORGIA AND THE SOUTH SANDWICH ISLANDS    GS      SGS     239
SPAIN                                           ES      ESP     724
SRI LANKA                                       LK      LKA     144
SUDAN                                           SD      SDN     736
SURINAME                                        SR      SUR     740
SVALBARD AND JAN MAYEN ISLANDS                  SJ      SJM     744
SWAZILAND                                       SZ      SWZ     748
SWEDEN                                          SE      SWE     752
SWITZERLAND                                     CH      CHE     756
SYRIAN ARAB REPUBLIC                            SY      SYR     760
TAIWAN                                          TW      TWN     158
TAJIKISTAN                                      TJ      TJK     762  
TANZANIA, UNITED REPUBLIC OF                    TZ      TZA     834
THAILAND                                        TH      THA     764
TIMOR-LESTE                                     TL      TLS     626
TOGO                                            TG      TGO     768
TOKELAU                                         TK      TKL     772
TONGA                                           TO      TON     776
TRINIDAD AND TOBAGO                             TT      TTO     780
TUNISIA                                         TN      TUN     788
TURKEY                                          TR      TUR     792
TURKMENISTAN                                    TM      TKM     795  
TURKS AND CAICOS ISLANDS                        TC      TCA     796
TUVALU                                          TV      TUV     798
UGANDA                                          UG      UGA     800
UKRAINE                                         UA      UKR     804
UNITED ARAB EMIRATES                            AE      ARE     784
UNITED KINGDOM                                  GB      GBR     826
UNITED STATES                                   US      USA     840
UNITED STATES MINOR OUTLYING ISLANDS            UM      UMI     581
URUGUAY                                         UY      URY     858
UZBEKISTAN                                      UZ      UZB     860  
VANUATU                                         VU      VUT     548
VATICAN CITY STATE (HOLY SEE)                   VA      VAT     336
VENEZUELA                                       VE      VEN     862
VIET NAM                                        VN      VNM     704
VIRGIN ISLANDS (BRITISH)                        VG      VGB     092
VIRGIN ISLANDS (U.S.)                           VI      VIR     850
WALLIS AND FUTUNA ISLANDS                       WF      WLF     876
WESTERN SAHARA                                  EH      ESH     732
YEMEN                                           YE      YEM     887
ZAMBIA                                          ZM      ZMB     894
ZIMBABWE                                        ZW      ZWE     716

C. GS1 General Specification
----------------------------
The GS1 General Specification defines a global standard for encoding data about 
products. Data is encoded as a series of number pairs where the first number, 
usually shown in (brackets) is an application identifier (AI), and the second 
is a formatted representation of the data. For example (21)6773 can be read as 
"Serial Number 6773" where the AI (21) signifies that the data is a serial 
number. Note that when using Zint AI data is entered using [square] brackets. 
This allows rounded brackets to be included in the data which is allowed by the 
specification. When the barcode symbol is generated these square brackets are 
replaced by rounded brackets in any text displayed. A list of valid AI numbers 
is given below. 

C.1 Application Identifiers [1]
---------------------------
00   Serial Shipping Container Code (SSCC)
01   Global Trade Item Number (GTIN)
02   # of containers
10   Batch Number
11   Production Date
13   Packaging Date
15   Sell by Date (Quality Control)
17   Expiration Date
20   Product Variant
21   Serial Number
22   HIBCC Quantity, Date, Batch and Link
23x  Lot Number
240  Additional Product Identification
250  Second Serial Number
30   Quantity Each
310y Product Net Weight in kg
311y Product Length/1st Dimension, in meters
312y Product Width/Diameter/2nd Dimension, in meters
313y Product Depth/Thickness/3rd Dimension, in meters
314y Product Area, in square meters
315y Product Volume, in liters
316y product Volume, in cubic meters
320y Product Net Weight, in pounds
321y Product Length/1st Dimension, in inches
322y Product Length/1st Dimension, in feet
323y Product Length/1st Dimension, in yards
324y Product Width/Diameter/2nd Dimension, in inches
325y Product Width/Diameter/2nd Dimension, in feet
326y Product Width/Diameter/2nd Dimension, in yards
327y Product Depth/Thickness/3rd Dimension, in inches
328y Product Depth/Thickness/3rd Dimension, in feet
329y Product Depth/Thickness/3rd Dimension, in yards
330y Container Gross Weight (kg)
331y Container Length/1st Dimension (Meters)
332y Container Width/Diameter/2nd Dimension (Meters)
333y Container Depth/Thickness/3rd Dimension (Meters)
334y Container Area (Square Meters)
335y Container Gross Volume (Liters)
336y Container Gross Volume (Cubic Meters)
340y Container Gross Weight (Pounds)
341y Container Length/1st Dimension, in inches
342y Container Length/1st Dimension, in feet
343y Container Length/1st Dimension in, in yards
344y Container Width/Diameter/2nd Dimension, in inches
345y Container Width/Diameter/2nd Dimension, in feet
346y Container Width/Diameter/2nd Dimension, in yards
347y Container Depth/Thickness/Height/3rd Dimension, in inches
348y Container Depth/Thickness/Height/3rd Dimension, in feet
349y Container Depth/Thickness/Height/3rd Dimension, in yards
350y Product Area (Square Inches)
351y Product Area (Square Feet)
352y Product Area (Square Yards)
353y Container Area (Square Inches)
354y Container Area (Square Feet)
355y Container Area (Suqare Yards)
356y Net Weight (Troy Ounces)
360y Product Volume (Quarts)
361y Product Volume (Gallons)
362y Container Gross Volume (Quarts)
363y Container Gross Volume (Gallons)
364y Product Volume (Cubic Inches)
365y Product Volume (Cubic Feet)
366y Product Volume (Cubic Yards)
367y Container Gross Volume (Cubic Inches)
368y Container Gross Volume (Cubic Feet)
369y Container Gross Volume (Cubic Yards)
37   Number of Units Contained
400  Customer Purchase Order Number
410  Ship To/Deliver To Location Code (Global Location Number)
411  Bill To/Invoice Location Code (Global Location Number)
412  Purchase From Location Code (Global Location Number)
420  Ship To/Deliver To Postal Code (Single Postal Authority)
421  Ship To/Deliver To Postal Code (Multiple Postal Authority)
8001 Roll Products - Width/Length/Core Diameter
8002 Electronic Serial Number (ESN) for Cellular Phone
8003 Global Returnable Asset Identifier
8004 Global Individual Asset Identifier
8005 Price per Unit of Measure
8100 Coupon Extended Code: Number System and Offer
8101 Coupon Extended Code: Number System, Offer, End of Offer
8102 Coupon Extended Code: Number System preceded by 090 Mutually Agreed 
     Between Trading Partners
91   Internal Company Codes
92   Internal Company Codes
93   Internal Company Codes
94   Internal Company Codes
95   Internal Company Codes
96   Internal Company Codes
97   Internal Company Codes
98   Internal Company Codes
99   Internal Company Codes

C.2 Fixed Length Fields
-----------------------
The GS1 Specification requires that some of the data to be encoded fits a 
standard length field. Zint will generate an error if the correct data lengths 
are not entered. The following table details which AIs have fixed length data 
fields and how long the data should be for each: 

------------------------------------
Application  |  Number of Characters
Identifier   |  (AI and Data Field)
------------------------------------
00           |  20
01           |  16
02           |  16
03           |  16
04           |  18
11           |  8
12           |  8
13           |  8
14           |  8
15           |  8
16           |  8
17           |  8
18           |  8
19           |  8
20           |  4
31           |  10
32           |  10
33           |  10
34           |  10
35           |  10
36           |  10
41           |  16
------------------------------------

[1] This information taken from Wikipedia (http://en.wikipedia.org/wiki/GS1) and 
used under the terms of the GNU Free Documentation License .