void PrepareInternalObjects()
{
emptyVideoFrame = new Interop.VideoFrame
{
Width = 0,
Height = 0,
LineStride = 0,
FourCC = _enableAlpha ?
Interop.FourCC.UYVA : Interop.FourCC.UYVY,
FrameFormat = Interop.FrameFormat.Progressive,
Data = IntPtr.Zero,
Metadata = IntPtr.Zero
};
if (_send == null)
{
_send = _captureMethod == CaptureMethod.GameView ?
SharedInstance.GameViewSend : Interop.Send.Create(_ndiName);
}
if (_converter == null)
{
_converter = new FormatConverter(_resources);
}
if (_onReadback == null)
{
_onReadback = OnReadback;
}
}
unsafe void OnReadback(AsyncGPUReadbackRequest request)
{
// Metadata retrieval
using (var metadata = _metadataQueue.Dequeue())
{
// Ignore errors.
if (request.hasError)
{
return;
}
// Ignore it if the NDI object has been already disposed.
if (_send == null || _send.IsInvalid || _send.IsClosed)
{
return;
}
// Pixel format (depending on alpha mode)
var fourcc = _enableAlpha ?
Interop.FourCC.UYVA : Interop.FourCC.UYVY;
// Readback data retrieval
var data = request.GetData <byte>();
var pdata = NativeArrayUnsafeUtility.GetUnsafeReadOnlyPtr(data);
// Data size verification
if (data.Length / sizeof(uint) !=
Util.FrameDataCount(_width, _height, _enableAlpha))
{
return;
}
// Frame data setup
var frame = new Interop.VideoFrame
{
Width = _width, Height = _height, LineStride = _width * 2,
FourCC = _enableAlpha ?
Interop.FourCC.UYVA : Interop.FourCC.UYVY,
FrameFormat = Interop.FrameFormat.Progressive,
Data = (System.IntPtr)pdata, Metadata = metadata
};
// Send via NDI
_send.SendVideoAsync(frame);
}
}
unsafe void OnReadback(AsyncGPUReadbackRequest req)
{
// Readback entry retrieval
var entry = _pool.FindEntry(req.GetData <byte>());
if (entry == null)
{
return;
}
// Invalid state detection
if (req.hasError || _send == null || _send.IsInvalid || _send.IsClosed)
{
// Do nothing but release the readback entry.
_pool.Free(entry);
return;
}
// Frame data
var frame = new Interop.VideoFrame
{
Width = entry.Width,
Height = entry.Height,
LineStride = entry.Stride,
FourCC = entry.FourCC,
FrameFormat = Interop.FrameFormat.Progressive,
Data = entry.ImagePointer,
Metadata = entry.MetadataPointer
};
// Async-send initiation
// This causes a synchronization for the last frame -- i.e., It locks
// the thread if the last frame is still under processing.
_send.SendVideoAsync(frame);
// We don't need the last frame anymore. Free it.
_pool.FreeMarkedEntry();
// Mark this frame to get freed in the next frame.
_pool.Mark(entry);
}
unsafe void OnReadback(AsyncGPUReadbackRequest request)
{
// Metadata retrieval
using (var metadata = _metadataQueue.Dequeue())
{
// Ignore errors.
if (request.hasError)
{
return;
}
// Ignore it if the NDI object has been already disposed.
if (_send == null || _send.IsInvalid || _send.IsClosed || !_enableVideoFrames)
{
return;
}
// Pixel format (depending on alpha mode)
var fourcc = _enableAlpha ?
Interop.FourCC.UYVA : Interop.FourCC.UYVY;
// Readback data retrieval
var data = request.GetData <byte>();
// NDI SDK Documentation p.21 re: send_video_v2_async
//
// If you call this and then free the pointer, your application will
// most likely crash in an NDI thread because the SDK is still using the video frame
// that was passed to the call.
// One possible solution is to ping pong between two buffers on
// alternating calls to NDIlib_send_send_video_v2_async
if (data.Length <= 0)
{
return;
}
if (videoFrameBuffer1 == null || videoFrameBuffer1.Length <= 0)
{
videoFrameBuffer1 = new byte[data.Length];
bufferHandle1 = GCHandle.Alloc(videoFrameBuffer1, GCHandleType.Pinned);
}
if (videoFrameBuffer2 == null || videoFrameBuffer2.Length <= 0)
{
videoFrameBuffer2 = new byte[data.Length];
bufferHandle2 = GCHandle.Alloc(videoFrameBuffer2, GCHandleType.Pinned);
}
// Handle frame size change
if (videoFrameBuffer1.Length != data.Length)
{
_send.SendVideoAsync(emptyVideoFrame);
bufferHandle1.Free();
videoFrameBuffer1 = new byte[data.Length];
bufferHandle1 = GCHandle.Alloc(videoFrameBuffer1, GCHandleType.Pinned);
}
if (videoFrameBuffer2.Length != data.Length)
{
_send.SendVideoAsync(emptyVideoFrame);
bufferHandle2.Free();
videoFrameBuffer2 = new byte[data.Length];
bufferHandle2 = GCHandle.Alloc(videoFrameBuffer2, GCHandleType.Pinned);
}
// Ping pong handles
var pdata = ping == 0 ? bufferHandle1.AddrOfPinnedObject() : bufferHandle2.AddrOfPinnedObject();
data.CopyTo(ping == 0 ? videoFrameBuffer1 : videoFrameBuffer2);
ping = ping == 0 ? 1 : 0;
// Data size verification
if (data.Length / sizeof(uint) !=
Util.FrameDataCount(_width, _height, _enableAlpha))
{
return;
}
// Frame data setup
var frame = new Interop.VideoFrame
{
Width = _width, Height = _height, LineStride = _width * 2,
FrameRateN = (int)frameRateND.x,
FrameRateD = (int)frameRateND.y,
FourCC = _enableAlpha ?
Interop.FourCC.UYVA : Interop.FourCC.UYVY,
FrameFormat = Interop.FrameFormat.Progressive,
Data = (System.IntPtr)pdata, Metadata = metadata
};
// Send via NDI
_send.SendVideoAsync(frame);
if (metadata != IntPtr.Zero)
{
_onVideoMetadataSent?.Invoke();
}
}
}
public FrameType Capture
(out VideoFrame video, IntPtr audio, IntPtr metadata, uint timeout)
=> _Capture(this, out video, audio, metadata, timeout);
