public static extern int avcodec_decode_video2(ref AVCodecContext pAVCodecContext, AVFrame* pAVFrame,
[MarshalAs(UnmanagedType.Bool)]out bool got_picture_ptr,
ref AVPacket packet);
public static extern AVError av_read_packet(ref AVFormatContext pAVFormatContext, ref AVPacket pAVPacket);
public static extern int av_write_frame(ref AVFormatContext pAVFormatContext, ref AVPacket pAVPacket);
public static extern AVError av_new_packet(ref AVPacket pAVPacket, int size);
public static extern void av_pkt_dump(IntPtr pFile, ref AVPacket pAVPacket, [MarshalAs(UnmanagedType.Bool)] bool dump_payload);
protected override bool DecodePacket(ref AVPacket packet)
{
// decode video frame
bool frameFinished = false;
int byteCount = FFmpeg.avcodec_decode_video2(ref m_avCodecCtx, m_avFrame, out frameFinished, ref packet);
if (byteCount < 0)
throw new DecoderException("Couldn't decode frame");
// copy data into our managed buffer
if (m_avFrame->data[0] == IntPtr.Zero)
m_bufferUsedSize = 0;
else
m_bufferUsedSize = FFmpeg.avpicture_layout((AVPicture*)m_avFrame, PixelFormat, Width, Height, m_buffer, m_buffer.Length);
if (m_bufferUsedSize < 0)
throw new DecoderException("Error copying decoded frame into managed memory");
return frameFinished;
}
public static extern int av_interleave_packet_per_dts(ref AVFormatContext pAVFormatContext, ref AVPacket p_out_AVPacket,
ref AVPacket pAVPacket, [MarshalAs(UnmanagedType.Bool)]bool flush);
public static extern AVError av_dup_packet(ref AVPacket pAVPacket);
/// <summary>
/// Free a packet
/// </summary>
/// <param name="pAVPacket">packet to free</param>
/// <remarks>
/// Inline function defined in avformat.h, thus its code must be duplicated here since inline functions
/// cannot be DllImported
/// </remarks>
public static void av_free_packet(ref AVPacket packet)
{
if (packet.destruct != null)
packet.destruct(ref packet);
}
protected abstract bool DecodePacket(ref AVPacket packet);
public static extern void av_destruct_packet_nofree(ref AVPacket pAVPacket);
public static extern int av_get_packet(ref AVIOContext s, ref AVPacket pkt, int size);
internal void EnqueueNextPacket()
{
AVPacket packet = new AVPacket();
FFmpeg.av_init_packet(ref packet);
if (FFmpeg.av_read_frame(ref FormatContext, ref packet) < 0)
throw new System.IO.EndOfStreamException();
DecoderStream dest = null;
if (m_streams.TryGetValue(packet.stream_index, out dest))
dest.PacketQueue.Enqueue(packet);
else
FFmpeg.av_free_packet(ref packet);
}
protected override bool DecodePacket(ref AVPacket packet)
{
int totalOutput = 0;
// Copy the data pointer to we can muck with it
int packetSize = packet.size;
byte* packetData = (byte*)packet.data;
// May be necessary to loop multiple times if more than one frame is in the compressed packet
fixed (byte* pBuffer = m_buffer)
do
{
if (m_disposed)
{
m_bufferUsedSize = 0;
return false;
}
int outputBufferUsedSize = m_buffer.Length - totalOutput; //Must be initialized before sending in as per docs
short* pcmWritePtr = (short*)(pBuffer + totalOutput);
int usedInputBytes = FFmpeg.avcodec_decode_audio2(ref m_avCodecCtx, pcmWritePtr, ref outputBufferUsedSize, packetData, packetSize);
if (usedInputBytes < 0) //Error in packet, ignore packet
break;
if (outputBufferUsedSize > 0)
totalOutput += outputBufferUsedSize;
packetData += usedInputBytes;
packetSize -= usedInputBytes;
}
while (packetSize > 0);
m_bufferUsedSize = totalOutput;
return true;
}
public static extern void av_free_packet(ref AVPacket pkt);
public static extern int av_get_packet(ref ByteIOContext pByteIOContext, ref AVPacket pAVPacket, int size);
public static extern void av_init_packet(ref AVPacket pkt);
private void EncodeAndWritePacket()
{
byte[] frameBuffer = new byte[FrameSize];
m_buffer.Read(frameBuffer, 0, frameBuffer.Length);
fixed (byte* pcmSamples = frameBuffer)
{
if (m_disposed)
throw new ObjectDisposedException(this.ToString());
AVPacket outPacket = new AVPacket();
FFmpeg.av_init_packet(ref outPacket);
byte[] buffer = new byte[FFmpeg.FF_MIN_BUFFER_SIZE];
fixed (byte* encodedData = buffer)
{
try
{
outPacket.size = FFmpeg.avcodec_encode_audio(ref m_avCodecCtx, encodedData, FFmpeg.FF_MIN_BUFFER_SIZE, (short*)pcmSamples);
outPacket.pts = m_avCodecCtx.coded_frame->pts;
outPacket.flags |= FFmpeg.PKT_FLAG_KEY;
outPacket.stream_index = m_avStream.index;
outPacket.data = (IntPtr)encodedData;
if (outPacket.size > 0)
{
if (FFmpeg.av_write_frame(ref m_avFormatCtx, ref outPacket) != 0)
throw new IOException("Error while writing encoded audio frame to file");
}
}
finally
{
FFmpeg.av_free_packet(ref outPacket);
}
}
}
}
