public static void WritePacket(this BinaryWriter writer, VideoPacket packet)
{
writer.Write(packet.Timestamp);
writer.Write(packet.FrameNumber);
writer.Write(packet.Height);
writer.Write(packet.Width);
writer.Write((byte) packet.FrameType);
writer.Write(packet.Data.Length);
writer.Write(packet.Data);
}
public static VideoPacket ReadVideoPacket(this BinaryReader reader)
{
var packet = new VideoPacket();
packet.Timestamp = reader.ReadInt64();
packet.FrameNumber = reader.ReadUInt32();
packet.Height = reader.ReadUInt16();
packet.Width = reader.ReadUInt16();
packet.FrameType = (FrameType) reader.ReadByte();
int dataSize = reader.ReadInt32();
packet.Data = reader.ReadBytes(dataSize);
return packet;
}
public bool TryDecode(ref VideoPacket packet, out VideoFrame frame)
{
if (_videoDecoder == null)
_videoDecoder = new VideoDecoder();
frame = new VideoFrame();
FFmpegNative.AVFrame avFrame;
if (_videoDecoder.TryDecode(ref packet.Data, out avFrame))
{
if (_videoConverter == null)
_videoConverter = new VideoConverter(PixelFormatHelper.ToAVPixelFormat(_pixelFormat));
frame.Timestamp = packet.Timestamp;
frame.FrameNumber = packet.FrameNumber;
frame.PixelFormat = _pixelFormat;
frame.Data = _videoConverter.ConvertFrame(avFrame);
return true;
}
return false;
}
protected override unsafe void Loop(CancellationToken token)
{
using (var tcpClient = new TcpClient(_config.Hostname, VideoPort))
using (NetworkStream stream = tcpClient.GetStream())
{
var packet = new VideoPacket();
byte[] packetData = null;
int offset = 0;
int frameStart = 0;
int frameEnd = 0;
var buffer = new byte[FrameBufferSize];
fixed (byte* pBuffer = &buffer[0])
while (token.IsCancellationRequested == false)
{
offset += stream.Read(buffer, offset, NetworkStreamReadSize);
if (packetData == null)
{
// lookup for a frame start
int maxSearchIndex = offset - sizeof (parrot_video_encapsulation_t);
for (int i = 0; i < maxSearchIndex; i++)
{
if (buffer[i] == 'P' &&
buffer[i + 1] == 'a' &&
buffer[i + 2] == 'V' &&
buffer[i + 3] == 'E')
{
parrot_video_encapsulation_t pve = *(parrot_video_encapsulation_t*) (pBuffer + i);
packetData = new byte[pve.payload_size];
packet = new VideoPacket
{
Timestamp = DateTime.UtcNow.Ticks,
FrameNumber = pve.frame_number,
Width = pve.display_width,
Height = pve.display_height,
FrameType = Convert(pve.frame_type),
Data = packetData
};
frameStart = i + pve.header_size;
frameEnd = frameStart + packet.Data.Length;
break;
}
}
if (packetData == null)
{
// frame is not detected
offset -= maxSearchIndex;
Array.Copy(buffer, maxSearchIndex, buffer, 0, offset);
}
}
if (packetData != null && offset >= frameEnd)
{
// frame acquired
Array.Copy(buffer, frameStart, packetData, 0, packetData.Length);
_videoPacketAcquired(packet);
// clean up acquired frame
packetData = null;
offset -= frameEnd;
Array.Copy(buffer, frameEnd, buffer, 0, offset);
}
Thread.Sleep(10);
}
}
}
public void EnqueuePacket(VideoPacket packet)
{
_packetQueue.Enqueue(packet);
}
private void OnVideoPacketAcquired(VideoPacket packet)
{
if (VideoPacketAcquired != null)
VideoPacketAcquired(packet);
}
