neko/server/internal/gst/gst.go
2020-01-13 08:05:38 +00:00

126 lines
3.1 KiB
Go

package gst
/*
#cgo pkg-config: gstreamer-1.0 gstreamer-app-1.0
#include "gst.h"
*/
import "C"
import (
"fmt"
"io"
"sync"
"unsafe"
"github.com/pion/webrtc/v2"
"github.com/pion/webrtc/v2/pkg/media"
)
func init() {
go C.gstreamer_send_start_mainloop()
}
// Pipeline is a wrapper for a GStreamer Pipeline
type Pipeline struct {
Pipeline *C.GstElement
tracks []*webrtc.Track
id int
codecName string
clockRate float32
}
var pipelines = make(map[int]*Pipeline)
var pipelinesLock sync.Mutex
const (
videoClockRate = 90000
audioClockRate = 48000
pcmClockRate = 8000
)
// CreatePipeline creates a GStreamer Pipeline
func CreatePipeline(codecName string, tracks []*webrtc.Track, pipelineSrc string) *Pipeline {
pipelineStr := "appsink name=appsink"
var clockRate float32
switch codecName {
case webrtc.VP8:
pipelineStr = pipelineSrc + " ! vp8enc error-resilient=partitions keyframe-max-dist=10 auto-alt-ref=true cpu-used=5 deadline=1 ! " + pipelineStr
clockRate = videoClockRate
case webrtc.VP9:
pipelineStr = pipelineSrc + " ! vp9enc ! " + pipelineStr
clockRate = videoClockRate
case webrtc.H264:
pipelineStr = pipelineSrc + " ! video/x-raw,format=I420 ! x264enc bframes=0 speed-preset=veryfast key-int-max=60 ! video/x-h264,stream-format=byte-stream ! " + pipelineStr
clockRate = videoClockRate
case webrtc.Opus:
pipelineStr = pipelineSrc + " ! opusenc ! " + pipelineStr
clockRate = audioClockRate
case webrtc.G722:
pipelineStr = pipelineSrc + " ! avenc_g722 ! " + pipelineStr
clockRate = audioClockRate
case webrtc.PCMU:
pipelineStr = pipelineSrc + " ! audio/x-raw, rate=8000 ! mulawenc ! " + pipelineStr
clockRate = pcmClockRate
case webrtc.PCMA:
pipelineStr = pipelineSrc + " ! audio/x-raw, rate=8000 ! alawenc ! " + pipelineStr
clockRate = pcmClockRate
default:
panic("Unhandled codec " + codecName)
}
pipelineStrUnsafe := C.CString(pipelineStr)
defer C.free(unsafe.Pointer(pipelineStrUnsafe))
pipelinesLock.Lock()
defer pipelinesLock.Unlock()
pipeline := &Pipeline{
Pipeline: C.gstreamer_send_create_pipeline(pipelineStrUnsafe),
tracks: tracks,
id: len(pipelines),
codecName: codecName,
clockRate: clockRate,
}
pipelines[pipeline.id] = pipeline
return pipeline
}
// Start starts the GStreamer Pipeline
func (p *Pipeline) Start() {
C.gstreamer_send_start_pipeline(p.Pipeline, C.int(p.id))
}
// Stop stops the GStreamer Pipeline
func (p *Pipeline) Stop() {
C.gstreamer_send_stop_pipeline(p.Pipeline)
}
//export goHandlePipelineBuffer
func goHandlePipelineBuffer(buffer unsafe.Pointer, bufferLen C.int, duration C.int, pipelineID C.int) {
pipelinesLock.Lock()
pipeline, ok := pipelines[int(pipelineID)]
pipelinesLock.Unlock()
if ok {
samples := uint32(pipeline.clockRate * (float32(duration) / 1000000000))
for _, t := range pipeline.tracks {
if err := t.WriteSample(media.Sample{Data: C.GoBytes(buffer, bufferLen), Samples: samples}); err != nil && err != io.ErrClosedPipe {
panic(err)
}
}
} else {
fmt.Printf("discarding buffer, no pipeline with id %d", int(pipelineID))
}
C.free(buffer)
}