mirror of
https://github.com/zint/zint
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602 lines
21 KiB
C
602 lines
21 KiB
C
/* gif.c - Handles output to gif file */
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/*
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libzint - the open source barcode library
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Copyright (C) 2009 - 2020 Robin Stuart <rstuart114@gmail.com>
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions
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are met:
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1. Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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2. Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in the
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documentation and/or other materials provided with the distribution.
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3. Neither the name of the project nor the names of its contributors
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may be used to endorse or promote products derived from this software
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without specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
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FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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SUCH DAMAGE.
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*/
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/* vim: set ts=4 sw=4 et : */
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#include <stdio.h>
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#include <string.h>
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#include "common.h"
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#include <math.h>
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#ifdef _MSC_VER
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#include <io.h>
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#include <fcntl.h>
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#include <malloc.h>
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#endif
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#define SSET "0123456789ABCDEF"
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typedef struct s_statestruct {
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unsigned char * pOut;
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unsigned char *pIn;
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unsigned int InLen;
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unsigned int OutLength;
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unsigned int OutPosCur;
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unsigned int OutByteCountPos;
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unsigned short ClearCode;
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unsigned short FreeCode;
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char fByteCountByteSet;
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unsigned char OutBitsFree;
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unsigned short NodeAxon[4096];
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unsigned short NodeNext[4096];
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unsigned char NodePix[4096];
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unsigned char colourCode[10];
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unsigned char colourPaletteIndex[10];
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int colourCount;
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} statestruct;
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/* Transform a Pixel to a lzw colourmap index and move to next pixel.
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* All colour values are listed in colourCode with corresponding palette index
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*/
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static unsigned char NextPaletteIndex(statestruct *pState)
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{
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unsigned char pixelColour;
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int colourIndex;
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pixelColour = *(pState->pIn);
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(pState->pIn)++;
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(pState->InLen)--;
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for (colourIndex = 0; colourIndex < pState->colourCount; colourIndex++) {
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if (pixelColour == pState->colourCode[colourIndex])
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return pState->colourPaletteIndex[colourIndex];
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}
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return 0; /* Not reached */
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}
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static char BufferNextByte(statestruct *pState) {
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(pState->OutPosCur)++;
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/* Check if this position is a byte count position
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* fg_f_bytecountbyte_set indicates, if byte count position bytes should be
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* inserted in general.
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* If this is true, and the distance to the last byte count position is 256
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* (e.g. 255 bytes in between), a byte count byte is inserted, and the value
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* of the last one is set to 255.
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* */
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if (pState->fByteCountByteSet && (pState->OutByteCountPos + 256 == pState->OutPosCur)) {
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(pState->pOut)[pState->OutByteCountPos] = 255;
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pState->OutByteCountPos = pState->OutPosCur;
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(pState->OutPosCur)++;
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}
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if (pState->OutPosCur >= pState->OutLength)
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return 1;
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(pState->pOut)[pState->OutPosCur] = 0x00;
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return 0;
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}
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static char AddCodeToBuffer(statestruct *pState, unsigned short CodeIn, unsigned char CodeBits) {
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/* Check, if we may fill up the current byte completely */
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if (CodeBits >= pState->OutBitsFree) {
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(pState->pOut)[pState->OutPosCur] |= (unsigned char)
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(CodeIn << (8 - pState->OutBitsFree));
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if (BufferNextByte(pState))
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return -1;
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CodeIn = (unsigned short) (CodeIn >> pState->OutBitsFree);
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CodeBits -= pState->OutBitsFree;
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pState->OutBitsFree = 8;
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/* Write a full byte if there are at least 8 code bits left */
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if (CodeBits >= pState->OutBitsFree) {
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(pState->pOut)[pState->OutPosCur] = (unsigned char) CodeIn;
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if (BufferNextByte(pState))
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return -1;
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CodeIn = (unsigned short) (CodeIn >> 8);
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CodeBits -= 8;
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}
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}
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/* The remaining bits of CodeIn fit in the current byte. */
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if (CodeBits > 0) {
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(pState->pOut)[pState->OutPosCur] |= (unsigned char)
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(CodeIn << (8 - pState->OutBitsFree));
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pState->OutBitsFree -= CodeBits;
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}
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return 0;
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}
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static void FlushStringTable(statestruct *pState) {
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unsigned short Pos;
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for (Pos = 0; Pos < pState->ClearCode; Pos++) {
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(pState->NodeAxon)[Pos] = 0;
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}
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}
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static unsigned short FindPixelOutlet(statestruct *pState, unsigned short HeadNode, unsigned char Byte) {
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unsigned short Outlet;
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Outlet = (pState->NodeAxon)[HeadNode];
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while (Outlet) {
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if ((pState->NodePix)[Outlet] == Byte)
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return Outlet;
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Outlet = (pState->NodeNext)[Outlet];
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}
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return 0;
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}
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static char NextCode(statestruct *pState, unsigned char * pPixelValueCur, unsigned char CodeBits) {
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unsigned short UpNode;
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unsigned short DownNode;
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/* start with the root node for last pixel chain */
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UpNode = *pPixelValueCur;
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if ((pState->InLen) == 0)
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return AddCodeToBuffer(pState, UpNode, CodeBits);
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*pPixelValueCur = NextPaletteIndex(pState);
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/* Follow the string table and the data stream to the end of the longest string that has a code */
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while (0 != (DownNode = FindPixelOutlet(pState, UpNode, *pPixelValueCur))) {
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UpNode = DownNode;
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if ((pState->InLen) == 0)
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return AddCodeToBuffer(pState, UpNode, CodeBits);
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*pPixelValueCur = NextPaletteIndex(pState);
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}
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/* Submit 'UpNode' which is the code of the longest string */
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if (AddCodeToBuffer(pState, UpNode, CodeBits))
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return -1;
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/* ... and extend the string by appending 'PixelValueCur' */
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/* Create a successor node for 'PixelValueCur' whose code is 'freecode' */
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(pState->NodePix)[pState->FreeCode] = *pPixelValueCur;
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(pState->NodeAxon)[pState->FreeCode] = (pState->NodeNext)[pState->FreeCode] = 0;
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/* ...and link it to the end of the chain emanating from fg_axon[UpNode]. */
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DownNode = (pState->NodeAxon)[UpNode];
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if (!DownNode) {
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(pState->NodeAxon)[UpNode] = pState->FreeCode;
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} else {
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while ((pState->NodeNext)[DownNode]) {
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DownNode = (pState->NodeNext)[DownNode];
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}
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(pState->NodeNext)[DownNode] = pState->FreeCode;
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}
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return 1;
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}
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static int gif_lzw(statestruct *pState, int paletteBitSize) {
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unsigned char PixelValueCur;
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unsigned char CodeBits;
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unsigned short Pos;
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// > Get first data byte
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if (pState->InLen == 0)
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return 0;
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PixelValueCur = NextPaletteIndex(pState);
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/* Number of bits per data item (=pixel)
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* We need at least a value of 2, otherwise the cc and eoi code consumes
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* the whole string table
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*/
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if (paletteBitSize == 1)
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paletteBitSize = 2;
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/* initial size of compression codes */
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CodeBits = paletteBitSize+1;
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pState->ClearCode = (1 << paletteBitSize);
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pState->FreeCode = pState->ClearCode+2;
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pState->OutBitsFree = 8;
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pState->OutPosCur = -1;
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pState->fByteCountByteSet = 0;
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if (BufferNextByte(pState))
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return 0;
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for (Pos = 0; Pos < pState->ClearCode; Pos++)
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(pState->NodePix)[Pos] = (unsigned char) Pos;
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FlushStringTable(pState);
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/* Write what the GIF specification calls the "code size". */
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(pState->pOut)[pState->OutPosCur] = paletteBitSize;
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/* Reserve first bytecount byte */
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if (BufferNextByte(pState))
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return 0;
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pState->OutByteCountPos = pState->OutPosCur;
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if (BufferNextByte(pState))
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return 0;
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pState->fByteCountByteSet = 1;
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/* Submit one 'ClearCode' as the first code */
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if (AddCodeToBuffer(pState, pState->ClearCode, CodeBits))
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return 0;
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for (;;) {
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char Res;
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/* generate and save the next code, which may consist of multiple input pixels. */
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Res = NextCode(pState, &PixelValueCur, CodeBits);
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if (Res < 0)
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return 0;
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//* Check for end of data stream */
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if (!Res) {
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/* submit 'eoi' as the last item of the code stream */
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if (AddCodeToBuffer(pState, (unsigned short) (pState->ClearCode + 1), CodeBits))
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return 0;
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pState->fByteCountByteSet = 0;
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if (pState->OutBitsFree < 8) {
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if (BufferNextByte(pState))
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return 0;
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}
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// > Update last bytecount byte;
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if (pState->OutByteCountPos < pState->OutPosCur) {
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(pState->pOut)[pState->OutByteCountPos] = (unsigned char) (pState->OutPosCur - pState->OutByteCountPos - 1);
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}
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pState->OutPosCur++;
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return pState->OutPosCur;
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}
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/* Check for currently last code */
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if (pState->FreeCode == (1U << CodeBits))
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CodeBits++;
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pState->FreeCode++;
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/* Check for full stringtable */
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if (pState->FreeCode == 0xfff) {
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FlushStringTable(pState);
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if (AddCodeToBuffer(pState, pState->ClearCode, CodeBits))
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return 0;
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CodeBits = (unsigned char) (1 + paletteBitSize);
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pState->FreeCode = (unsigned short) (pState->ClearCode + 2);
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}
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}
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}
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/*
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* Called function to save in gif format
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*/
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INTERNAL int gif_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf) {
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unsigned char outbuf[10];
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FILE *gif_file;
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unsigned short usTemp;
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int byte_out;
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int colourCount;
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unsigned char paletteRGB[10][3];
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int paletteCount, paletteCountCur, paletteIndex;
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int pixelIndex;
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int paletteBitSize;
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int paletteSize;
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statestruct State;
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int transparent_index;
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int bgindex = -1, fgindex = -1;
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unsigned char backgroundColourIndex;
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unsigned char RGBCur[3];
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unsigned char RGBUnused[3] = {0,0,0};
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int colourIndex;
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int fFound;
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unsigned char pixelColour;
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/* Allow for overhead of 4 == code size + byte count + overflow byte + zero terminator */
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unsigned int lzoutbufSize = symbol->bitmap_height * symbol->bitmap_width + 4;
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#ifdef _MSC_VER
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char * lzwoutbuf;
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#endif
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#ifndef _MSC_VER
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char lzwoutbuf[lzoutbufSize];
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#else
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lzwoutbuf = (char *) _alloca(lzoutbufSize);
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#endif /* _MSC_VER */
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/* Open output file in binary mode */
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if ((symbol->output_options & BARCODE_STDOUT) != 0) {
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#ifdef _MSC_VER
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if (-1 == _setmode(_fileno(stdout), _O_BINARY)) {
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strcpy(symbol->errtxt, "610: Can't open output file");
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return ZINT_ERROR_FILE_ACCESS;
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}
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#endif
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gif_file = stdout;
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} else {
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if (!(gif_file = fopen(symbol->outfile, "wb"))) {
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strcpy(symbol->errtxt, "611: Can't open output file");
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return ZINT_ERROR_FILE_ACCESS;
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}
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}
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/*
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* Build a table of the used palette items.
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* Currently, there are the following 10 colour codes:
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* '0': standard background
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* '1': standard foreground
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* 'W': white
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* 'C': cyan
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* 'B': blue
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* 'M': magenta
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* 'R': red
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* 'Y': yellow
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* 'G': green
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* 'K': black
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* '0' and '1' may be identical to one of the other values
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*
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* A data structure is set up as follows:
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* state.colourCode: list of colour codes
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* paletteIndex: palette index of the corresponding colour code
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* There are colourCount entries in the upper lists.
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* paletteRGB: RGB value at the palette position
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* There are paletteCount entries.
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* This value is smaller to colourCount, if multiple colour codes have the
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* same RGB value and point to the same palette value.
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* Example:
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* 0 1 W K are present. 0 is equal to white, while 1 is blue
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* The resulting tables are:
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* paletteItem: ['0']=0 (white), ['1']=1 (blue), ['W']=0 (white),
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* ['K']=2 (black)
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* Thus, there are 4 colour codes and 3 palette entries.
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*/
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colourCount = 0;
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paletteCount = 0;
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/* loop over all pixels */
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for ( pixelIndex = 0; pixelIndex < (symbol->bitmap_height * symbol->bitmap_width); pixelIndex++)
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{
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fFound = 0;
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/* get pixel colour code */
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pixelColour = pixelbuf[pixelIndex];
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/* look, if colour code is already in colour list */
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for (colourIndex = 0; colourIndex < colourCount; colourIndex++) {
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if ((State.colourCode)[colourIndex] == pixelColour) {
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fFound = 1;
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break;
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}
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}
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/* If colour is already present, go to next colour code */
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if (fFound)
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continue;
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/* Colour code not present - add colour code */
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/* Get RGB value */
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switch (pixelColour) {
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case '0': /* standard background */
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RGBCur[0] = (unsigned char) (16 * ctoi(symbol->bgcolour[0])) + ctoi(symbol->bgcolour[1]);
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RGBCur[1] = (unsigned char) (16 * ctoi(symbol->bgcolour[2])) + ctoi(symbol->bgcolour[3]);
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RGBCur[2] = (unsigned char) (16 * ctoi(symbol->bgcolour[4])) + ctoi(symbol->bgcolour[5]);
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break;
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case '1': /* standard foreground */
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RGBCur[0] = (unsigned char) (16 * ctoi(symbol->fgcolour[0])) + ctoi(symbol->fgcolour[1]);
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RGBCur[1] = (unsigned char) (16 * ctoi(symbol->fgcolour[2])) + ctoi(symbol->fgcolour[3]);
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RGBCur[2] = (unsigned char) (16 * ctoi(symbol->fgcolour[4])) + ctoi(symbol->fgcolour[5]);
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break;
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case 'W': /* white */
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RGBCur[0] = 255; RGBCur[1] = 255; RGBCur[2] = 255;
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break;
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case 'C': /* cyan */
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RGBCur[0] = 0; RGBCur[1] = 255; RGBCur[2] = 255;
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break;
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case 'B': /* blue */
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RGBCur[0] = 0; RGBCur[1] = 0; RGBCur[2] = 255;
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break;
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case 'M': /* magenta */
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RGBCur[0] = 255; RGBCur[1] = 0; RGBCur[2] = 255;
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break;
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case 'R': /* red */
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RGBCur[0] = 255; RGBCur[1] = 0; RGBCur[2] = 0;
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break;
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case 'Y': /* yellow */
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RGBCur[0] = 255; RGBCur[1] = 255; RGBCur[2] = 0;
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break;
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case 'G': /* green */
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RGBCur[0] = 0; RGBCur[1] = 255; RGBCur[2] = 0;
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break;
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case 'K': /* black */
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RGBCur[0] = 0; RGBCur[1] = 0; RGBCur[2] = 0;
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break;
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default: /* error case - return */
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strcpy(symbol->errtxt, "611: unknown pixel colour");
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return ZINT_ERROR_INVALID_DATA;
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}
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/* Search, if RGB value is already present */
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fFound = 0;
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for (paletteIndex = 0; paletteIndex < paletteCount; paletteIndex++) {
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if (RGBCur[0] == paletteRGB[paletteIndex][0]
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&& RGBCur[1] == paletteRGB[paletteIndex][1]
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&& RGBCur[2] == paletteRGB[paletteIndex][2])
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{
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fFound = 1;
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break;
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}
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}
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/* RGB not present, add it */
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if (!fFound) {
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paletteIndex = paletteCount;
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paletteRGB[paletteIndex][0] = RGBCur[0];
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paletteRGB[paletteIndex][1] = RGBCur[1];
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paletteRGB[paletteIndex][2] = RGBCur[2];
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paletteCount++;
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if (pixelColour == '0') bgindex = paletteIndex;
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if (pixelColour == '1') fgindex = paletteIndex;
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}
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/* Add palette index to current colour code */
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(State.colourCode)[colourCount] = pixelColour;
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(State.colourPaletteIndex)[colourCount] = paletteIndex;
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colourCount++;
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}
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State.colourCount = colourCount;
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/* Set transparency */
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/* Note: does not allow both transparent foreground and background -
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* background takes prioroty */
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transparent_index = -1;
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if (strlen(symbol->fgcolour) > 6) {
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if ((symbol->fgcolour[6] == '0') && (symbol->fgcolour[7] == '0')) {
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// Transparent foreground
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transparent_index = fgindex;
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}
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}
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if (strlen(symbol->bgcolour) > 6) {
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if ((symbol->bgcolour[6] == '0') && (symbol->bgcolour[7] == '0')) {
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// Transparent background
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transparent_index = bgindex;
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}
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}
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/* find palette bit size from palette size*/
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/* 1,2 -> 1, 3,4 ->2, 5,6,7,8->3 */
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paletteBitSize = 0;
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paletteCountCur = paletteCount-1;
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while (paletteCountCur != 0) {
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paletteBitSize++;
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paletteCountCur >>= 1;
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}
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/* Minimum is 1 */
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if (paletteBitSize == 0)
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paletteBitSize = 1;
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/* palette size 2 ^ bit size */
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paletteSize = 1<<paletteBitSize;
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/* GIF signature (6) */
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memcpy(outbuf, "GIF87a", 6);
|
|
if (transparent_index != -1)
|
|
outbuf[4] = '9';
|
|
|
|
fwrite(outbuf, 6, 1, gif_file);
|
|
/* Screen Descriptor (7) */
|
|
/* Screen Width */
|
|
usTemp = (unsigned short) symbol->bitmap_width;
|
|
outbuf[0] = (unsigned char) (0xff & usTemp);
|
|
outbuf[1] = (unsigned char) ((0xff00 & usTemp) / 0x100);
|
|
/* Screen Height */
|
|
usTemp = (unsigned short) symbol->bitmap_height;
|
|
outbuf[2] = (unsigned char) (0xff & usTemp);
|
|
outbuf[3] = (unsigned char) ((0xff00 & usTemp) / 0x100);
|
|
/* write ImageBits-1 to the three least significant bits of byte 5 of
|
|
* the Screen Descriptor
|
|
* Bits 76543210
|
|
* 1 : Global colour map
|
|
* 111 : 8 bit colour depth of the palette
|
|
* 0 : Not ordered in decreasing importance
|
|
* xxx : palette bit zize - 1
|
|
*/
|
|
outbuf[4] = (unsigned char) (0xf0 | (0x7 & (paletteBitSize - 1)));
|
|
|
|
/*
|
|
* Background colour index
|
|
* Default to 0. If colour code 0 or K is present, it is used as index
|
|
*/
|
|
|
|
backgroundColourIndex = 0;
|
|
for (colourIndex = 0; colourIndex < colourCount; colourIndex++) {
|
|
if ((State.colourCode)[colourIndex] == '0' || (State.colourCode)[colourIndex] == 'W') {
|
|
backgroundColourIndex = (State.colourPaletteIndex)[colourIndex];
|
|
break;
|
|
}
|
|
}
|
|
outbuf[5] = backgroundColourIndex;
|
|
/* Byte 7 must be 0x00 */
|
|
outbuf[6] = 0x00;
|
|
fwrite(outbuf, 7, 1, gif_file);
|
|
/* Global Color Table (paletteSize*3) */
|
|
fwrite(paletteRGB, 3*paletteCount, 1, gif_file);
|
|
/* add unused palette items to fill palette size */
|
|
for (paletteIndex = paletteCount; paletteIndex < paletteSize; paletteIndex++) {
|
|
fwrite(RGBUnused, 3, 1, gif_file);
|
|
}
|
|
|
|
/* Graphic control extension (8) */
|
|
/* A graphic control extension block is used for overlay gifs.
|
|
* This is necessary to define a transparent color.
|
|
*/
|
|
if (transparent_index != -1) {
|
|
/* Extension Introducer = '!' */
|
|
outbuf[0] = '\x21';
|
|
/* Graphic Control Label */
|
|
outbuf[1] = '\xf9';
|
|
/* Block Size */
|
|
outbuf[2] = 4;
|
|
/* Packet fields:
|
|
* 3 Reserved
|
|
* 3 Disposal Method: 0 No Action, 1 No Dispose, 2: Background, 3: Prev.
|
|
* 1 User Input Flag: 0: no user input, 1: user input
|
|
* 1 Transparent Color Flag: 0: No Transparency, 1: Transparency index
|
|
*/
|
|
outbuf[3] = 1;
|
|
/* Delay Time */
|
|
outbuf[4] = 0;
|
|
outbuf[5] = 0;
|
|
/* Transparent Color Index */
|
|
outbuf[6] = (unsigned char) transparent_index;
|
|
/* Block Terminator */
|
|
outbuf[7] = 0;
|
|
fwrite(outbuf, 8, 1, gif_file);
|
|
}
|
|
/* Image Descriptor */
|
|
/* Image separator character = ',' */
|
|
outbuf[0] = 0x2c;
|
|
/* "Image Left" */
|
|
outbuf[1] = 0x00;
|
|
outbuf[2] = 0x00;
|
|
/* "Image Top" */
|
|
outbuf[3] = 0x00;
|
|
outbuf[4] = 0x00;
|
|
/* Image Width (low byte first) */
|
|
outbuf[5] = (unsigned char) (0xff & symbol->bitmap_width);
|
|
outbuf[6] = (unsigned char) ((0xff00 & symbol->bitmap_width) / 0x100);
|
|
/* Image Height */
|
|
outbuf[7] = (unsigned char) (0xff & symbol->bitmap_height);
|
|
outbuf[8] = (unsigned char) ((0xff00 & symbol->bitmap_height) / 0x100);
|
|
|
|
/* Byte 10 contains the interlaced flag and
|
|
* information on the local color table.
|
|
* There is no local color table if its most significant bit is reset.
|
|
*/
|
|
outbuf[9] = 0x00;
|
|
fwrite(outbuf, 10, 1, gif_file);
|
|
|
|
/* prepare state array */
|
|
State.pIn = pixelbuf;
|
|
State.InLen = symbol->bitmap_height * symbol->bitmap_width;
|
|
State.pOut = (unsigned char *) lzwoutbuf;
|
|
State.OutLength = lzoutbufSize;
|
|
|
|
/* call lzw encoding */
|
|
byte_out = gif_lzw(&State, paletteBitSize);
|
|
if (byte_out <= 0) {
|
|
fclose(gif_file);
|
|
return ZINT_ERROR_MEMORY;
|
|
}
|
|
fwrite(lzwoutbuf, byte_out, 1, gif_file);
|
|
|
|
/* GIF terminator */
|
|
fputc('\x3b', gif_file);
|
|
fclose(gif_file);
|
|
|
|
return 0;
|
|
}
|