/// <summary>
/// Creates a video capture/output format.
/// </summary>
/// <param name="device">The parental Video4Linux device.</param>
/// <param name="type">The buffer type the format belongs to.</param>
internal V4LOverlayFormat(V4LDevice device, v4l2_buf_type type)
{
this.device = device;
format = new v4l2_format();
format.type = type;
}
internal V4LVideoFormat(V4LDevice device, v4l2_buf_type type)
{
this.device = device;
format = new v4l2_format();
format.type = type;
getFormat();
}
/// <summary>
/// Stops the streaming I/O.
/// </summary>
public void StopStreaming()
{
// nothing to do here if we use read/write to capture
if (captureMethod == CaptureMethod.ReadWrite)
{
return;
}
// destroy the buffers
buffers = new List <Analog.Buffer>();
v4l2_buf_type type = v4l2_buf_type.VideoCapture;
if (ioControl.StreamingOff(ref type) < 0)
{
throw new Exception("VIDIOC_STREAMOFF");
}
}
private unsafe byte[] ProcessCaptureData()
{
fixed(V4l2FrameBuffer *buffers = &ApplyFrameBuffers()[0])
{
// Start data stream
v4l2_buf_type type = v4l2_buf_type.V4L2_BUF_TYPE_VIDEO_CAPTURE;
Interop.ioctl(_deviceFileDescriptor, (int)VideoSettings.VIDIOC_STREAMON, new IntPtr(&type));
byte[] dataBuffer = GetFrameData(buffers);
// Close data stream
Interop.ioctl(_deviceFileDescriptor, (int)VideoSettings.VIDIOC_STREAMOFF, new IntPtr(&type));
UnmappingFrameBuffers(buffers);
return(dataBuffer);
}
}
public override unsafe void CaptureContinuous(CancellationToken token)
{
_capturing = true;
fixed(V4l2FrameBuffer *buffers = &ApplyFrameBuffers()[0])
{
// Start data stream
v4l2_buf_type type = v4l2_buf_type.V4L2_BUF_TYPE_VIDEO_CAPTURE;
Interop.ioctl(_deviceFileDescriptor, V4l2Request.VIDIOC_STREAMON, new IntPtr(&type));
while (!token.IsCancellationRequested)
{
NewImageBufferReady?.Invoke(this, GetFrameDataPooled(buffers));
}
// Close data stream
Interop.ioctl(_deviceFileDescriptor, V4l2Request.VIDIOC_STREAMOFF, new IntPtr(&type));
UnmappingFrameBuffers(buffers);
}
_capturing = false;
}
/// <summary>
/// Starts the streaming I/O.
/// </summary>
public void StartStreaming()
{
// nothing to do here if we use read/write to capture
if (captureMethod == CaptureMethod.ReadWrite)
{
return;
}
// request the streaming buffers if necessary
if (buffers == null || buffers.Count != bufferCount)
{
requestBuffers();
}
// make sure that all buffers are in the incoming queue
enqueueAllBuffers();
v4l2_buf_type type = v4l2_buf_type.VideoCapture;
if (ioControl.StreamingOn(ref type) < 0)
{
throw new Exception("VIDIOC_STREAMON");
}
}
/// <summary>
/// Calls VIDIOC_STREAMOFF.
/// </summary>
public int StreamingOff(ref v4l2_buf_type type)
{
return ioctl(deviceHandle, v4l2_operation.StreamingOff, ref type);
}
ioctl(int device, v4l2_operation request, ref v4l2_buf_type argp);
private static extern int ioctl(int device, v4l2_operation request, ref v4l2_buf_type argp);
/// <summary>
/// Calls VIDIOC_STREAMOFF.
/// </summary>
public int StreamingOff(ref v4l2_buf_type type)
{
return(ioctl(deviceHandle, v4l2_operation.StreamingOff, ref type));
}
ioctl(int device, v4l2_operation request, ref v4l2_buf_type argp);
