Exemple #1
0
func avpicture_get_size(fmt int32, width, height int) int {
	return int(C.avpicture_get_size(fmt, C.int(width), C.int(height)))
}
func (c *Decoder) decodeVideo(p Packet) *Frame {
	if !c.Valid {
		//println("try to decode with an invalid Decoder")
		return nil
	}
	//println("try to decode with a valid Decoder")

	packet := new(C.AVPacket)
	C.av_init_packet(packet)
	defer C.av_free_packet(packet)

	packet.pts = C.int64_t(p.Pts)
	packet.dts = C.int64_t(p.Dts)
	packet.size = C.int(p.Size)
	//packet.data=&C.uint8_t(make([]byte, p.Size)[0])
	//myBytes:=make([]byte,p.Size);
	/*
	   var pb *byte
	   if(len(p.Data)>0){
	   //println("Data > 0")
	   pb=&p.Data[0]
	   }*/
	packet.data = (*C.uint8_t)(unsafe.Pointer(&p.Data[0]))
	//    println(p.Data)
	//    println(pb)
	//    println(packet.data)
	//    packet.data=unsafe.Pointer(p.Data)
	//    for i:= 0; i < re.Size; i++ {
	//      re.Data[i] = data[i];
	//    }
	packet.stream_index = C.int(p.Stream)
	packet.flags = C.int(p.Flags)
	packet.duration = C.int(p.Duration)
	packet.pos = C.int64_t(p.Pos)

	height := c.Ctx.height
	width := c.Ctx.width
	var frame *Frame = new(Frame)

	numBytes := C.avpicture_get_size(0, width, height)
	//_size = numBytes;
	//_buffer := (*C.uint8_t) (C.av_malloc(C.uint(numBytes)));
	if numBytes > 0 {
		var buffer []byte = make([]byte, numBytes)
		var pbuffer *byte = &buffer[0]
		// C.memset((*C.uint8_t)(_buffer), 0, C.size_t(numBytes));
		// Assign appropriate parts of buffer to image planes
		//var picture * C.AVPicture=(*C.AVPicture)(unsafe.Pointer(frame))
		//println(frame)
		//println(picture)
		//:=&frame
		//854x480
		C.avpicture_fill((*C.AVPicture)(unsafe.Pointer(frame)), (*C.uint8_t)(unsafe.Pointer(pbuffer)), 0, width, height)
	}

	//frameFinished:=C.int(0)
	var frameFinished *C.int = new(C.int)
	//bytes_decoded:=

	C.avcodec_decode_video2(c.Ctx, (*C.AVFrame)(unsafe.Pointer(frame)), frameFinished, packet)
	frame.pts = packet.pts
	//frame.dts=packet.dts

	/*
	   //C.avcodec_decode_video2(nil,nil,nil,nil)

	   header:=fmt.Sprintf("P5\n%d %d\n255\n",width,height)

	   file, err := os.Open("test.ppm", os.O_CREATE|os.O_TRUNC|os.O_RDWR, 0666)

	   if(err!=nil){
	   println("error while openning file")
	   }
	   file.WriteString(header)
	   linesize:=int(frame.linesize[0])
	   //println(linesize)
	   data:=make([]byte, width)
	   tmpdata:=(*(*[1<<30]byte)(unsafe.Pointer(frame.data[0])))[0:numBytes]
	   //    for i:= 0; i < 1; i++ {
	   //      data[i] = tmpdata[i];
	   //    }

	   for i := 0; i < int(height); i++{
	   for a:= 0; a < int(width); a++ {
	   data[a] = tmpdata[(i*linesize)+a];
	   }
	   file.Write(data);
	   }

	   file.Close()*/
	//ioutil.WriteFile("test.data", header,0755)
	//println("bla fasel")
	//println(bytes_decoded)
	//println(*frameFinished)
	return frame
}
Exemple #3
0
//Calculate the size in bytes that a picture of the given width and height would occupy if stored in the given picture format.
//int 	avpicture_get_size (enum AVPixelFormat pix_fmt, int width, int height)
func Avpicture_get_size(pf AVPixelFormat, w, h int) int {
	return int(C.avpicture_get_size((C.enum_AVPixelFormat)(pf), C.int(w), C.int(h)))
}
Exemple #4
0
func (self *Decoder) Start(videoStream, audioStream *C.AVStream,
	scaleWidth, scaleHeight C.int) *Decoder {

	self.running = true
	self.duration = time.Duration(self.FormatContext.duration * C.AV_TIME_BASE / 1000)
	vCodecCtx := videoStream.codec
	aCodecCtx := audioStream.codec

	self.durationPerSample = time.Second / time.Duration(aCodecCtx.sample_rate)

	// frame pool
	poolSize := 16
	pool := make(chan *C.AVFrame, poolSize)
	self.pool = pool
	numBytes := C.size_t(C.avpicture_get_size(C.PIX_FMT_YUV420P, scaleWidth, scaleHeight))
	for i := 0; i < poolSize; i++ {
		frame := C.av_frame_alloc()
		self.frames = append(self.frames, frame)
		buffer := (*C.uint8_t)(unsafe.Pointer(C.av_malloc(numBytes)))
		self.buffers = append(self.buffers, buffer)
		C.avpicture_fill((*C.AVPicture)(unsafe.Pointer(frame)), buffer, C.PIX_FMT_YUV420P,
			scaleWidth, scaleHeight)
		pool <- frame
	}

	// decode
	self.frameChan = make(chan *C.AVFrame, 512)
	go func() {
		runtime.LockOSThread()

		// scale context
		scaleContext := C.sws_getCachedContext(nil, vCodecCtx.width, vCodecCtx.height, vCodecCtx.pix_fmt,
			scaleWidth, scaleHeight, C.PIX_FMT_YUV420P, C.SWS_LANCZOS, nil, nil, nil)
		if scaleContext == nil {
			log.Fatal("get scale context failed")
		}

		// resample context
		resampleContext := C.swr_alloc_set_opts(nil,
			C.AV_CH_LAYOUT_STEREO, C.AV_SAMPLE_FMT_FLT, aCodecCtx.sample_rate,
			C.int64_t(aCodecCtx.channel_layout), aCodecCtx.sample_fmt, aCodecCtx.sample_rate,
			0, nil)
		if resampleContext == nil {
			log.Fatal("get resample context failed")
		}
		C.swr_init(resampleContext)

		var packet C.AVPacket
		var frameFinished C.int
		var pts int64
		var packetTime time.Duration
		vFrame := C.av_frame_alloc()
		aFrame := C.av_frame_alloc()
		videoIndex := videoStream.index
		audioIndex := audioStream.index
		resampleBuffer := (*C.uint8_t)(C.av_malloc(4096 * 8))
		resampleBufferp := &resampleBuffer

		self.Timer = NewTimer()

		// decode
		for self.running {

			// seek
			if self.seekTarget > 0 {
				if C.av_seek_frame(self.FormatContext, -1,
					C.int64_t(float64(self.seekNext)/float64(time.Second)*float64(C.AV_TIME_BASE)),
					C.AVSEEK_FLAG_BACKWARD) < 0 {
					log.Fatal("seek error")
				}
				for _, codecCtx := range self.openedCodecs {
					C.avcodec_flush_buffers(codecCtx)
				}
				p("frame seek done\n")
			}

		read_packet:
			// read packet
			C.av_free_packet(&packet)
			if C.av_read_frame(self.FormatContext, &packet) < 0 { // read packet
				log.Fatal("read frame error") //TODO stop gracefully
			}

			// get packet time
			if packet.dts != C.AV_NOPTS_VALUE {
				pts = int64(packet.dts)
			} else {
				pts = 0
			}
			if packet.stream_index == videoIndex {
				packetTime = time.Duration(float64(pts) * float64(C.av_q2d(videoStream.time_base)) * float64(time.Second))
			} else if packet.stream_index == audioIndex {
				packetTime = time.Duration(float64(pts) * float64(C.av_q2d(audioStream.time_base)) * float64(time.Second))
			} else { // ignore packet
				goto read_packet
			}
			p("packet time %v at timer time %v\n", packetTime, self.Timer.Now())

			// check seek
			if self.seekTarget > 0 && packetTime > 0 { // if packet time cannot determined, skip
				if packetTime < self.seekTarget { // seek again
					self.seekNext += self.seekStep
					p("seek again %v\n", self.seekNext)
				} else { // seek ok
					p("seek ok\n")
					self.seekTarget = 0
					self.Timer.Jump(packetTime - self.Timer.Now())
				}
			}

			// decode
			if packet.stream_index == videoIndex { // decode video
				if C.avcodec_decode_video2(vCodecCtx, vFrame, &frameFinished, &packet) < 0 {
					continue // bad packet
				}
				if frameFinished <= 0 {
					goto read_packet // frame not complete
				}
				bufFrame := <-pool        // get frame buffer
				C.sws_scale(scaleContext, // scale
					&vFrame.data[0], &vFrame.linesize[0], 0, vCodecCtx.height,
					&bufFrame.data[0], &bufFrame.linesize[0])
				bufFrame.pts = C.int64_t(packetTime) // set packet time
				self.frameChan <- bufFrame           // push to queue
				p("video frame %v\n", packetTime)

			} else if packet.stream_index == audioIndex { // decode audio
			decode_audio_packet:
				l := C.avcodec_decode_audio4(aCodecCtx, aFrame, &frameFinished, &packet)
				if l < 0 {
					continue // bad packet
				}
				if frameFinished <= 0 {
					goto read_packet // frame not complete
				}
				if frameFinished > 0 { // frame finished
					n := C.swr_convert(resampleContext, resampleBufferp, 4096,
						aFrame.extended_data, aFrame.nb_samples)
					if n != aFrame.nb_samples {
						log.Fatal("audio resample failed")
					}
					self.audioFrames <- &AudioFrame{
						time: packetTime,
						data: C.GoBytes(unsafe.Pointer(resampleBuffer), n*8),
					}
				}
				if l != packet.size { // multiple frame packet
					packet.size -= l
					packet.data = (*C.uint8_t)(unsafe.Pointer(uintptr(unsafe.Pointer(packet.data)) + uintptr(l)))
					goto decode_audio_packet
				}
				p("audio frame %v\n", packetTime)

			} else { // other stream
				goto read_packet
			}

		}
	}()

	// sync video
	go func() {
		maxDelta := (time.Second / time.Duration(C.av_q2d(videoStream.r_frame_rate)/10))
		for frame := range self.frameChan {
			delta := time.Duration(frame.pts) - self.Timer.Now()
			p("video frame %v, delta %v, max delta %v\n", time.Duration(frame.pts), delta, maxDelta)
			if delta > 0 {
				if delta > maxDelta {
					self.Timer.Jump(delta)
					print("timer jumped\n")
				} else {
					time.Sleep(delta)
				}
			} else if delta < 0 { // drop frame
				self.RecycleFrame(frame)
				continue
			}
			self.timedFrames <- frame
		}
	}()

	return self
}