public VideoChannel (AVAssetReaderOutput readerOutput, AVAssetWriterInput writerInput, IVideoTransformer transformer)
: base(readerOutput, writerInput)
{
if (transformer == null)
throw new ArgumentNullException ("transformer");
this.transformer = transformer;
var adaptorAttrs = new CVPixelBufferAttributes {
PixelFormatType = CVPixelFormatType.CV32BGRA
};
adaptor = new AVAssetWriterInputPixelBufferAdaptor (WriterInput, adaptorAttrs);
}
bool SetupCaptureSession ()
{
// configure the capture session for low resolution, change this if your code
// can cope with more data or volume
session = new AVCaptureSession {
SessionPreset = AVCaptureSession.PresetMedium
};
// create a device input and attach it to the session
var captureDevice = AVCaptureDevice.DefaultDeviceWithMediaType (AVMediaType.Video);
if (captureDevice == null) {
Console.WriteLine ("No captureDevice - this won't work on the simulator, try a physical device");
return false;
}
//Configure for 15 FPS. Note use of LockForConigfuration()/UnlockForConfiguration()
NSError error = null;
captureDevice.LockForConfiguration (out error);
if (error != null) {
Console.WriteLine (error);
captureDevice.UnlockForConfiguration ();
return false;
}
if (UIDevice.CurrentDevice.CheckSystemVersion (7, 0))
captureDevice.ActiveVideoMinFrameDuration = new CMTime (1, 15);
captureDevice.UnlockForConfiguration ();
var input = AVCaptureDeviceInput.FromDevice (captureDevice);
if (input == null) {
Console.WriteLine ("No input - this won't work on the simulator, try a physical device");
return false;
}
session.AddInput (input);
// create a VideoDataOutput and add it to the sesion
var settings = new CVPixelBufferAttributes {
PixelFormatType = CVPixelFormatType.CV32BGRA
};
using (var output = new AVCaptureVideoDataOutput { WeakVideoSettings = settings.Dictionary }) {
queue = new DispatchQueue ("myQueue");
outputRecorder = new OutputRecorder ();
output.SetSampleBufferDelegate (outputRecorder, queue);
session.AddOutput (output);
}
session.StartRunning ();
return true;
}
public ReadWriteSampleBufferChannel (AVAssetReaderOutput localAssetReaderOutput,
AVAssetWriterInput localAssetWriterInput,
bool useAdaptor)
{
_assetReaderOutput = localAssetReaderOutput;
_assetWriterInput = localAssetWriterInput;
_useAdaptor = useAdaptor;
if (_useAdaptor) {
var adaptorAttrs = new CVPixelBufferAttributes {
PixelFormatType = CVPixelFormatType.CV32BGRA
};
_adaptor = AVAssetWriterInputPixelBufferAdaptor.FromInput (localAssetWriterInput, adaptorAttrs.Dictionary);
}
_serializationQueue = new DispatchQueue ("ReadWriteSampleBufferChannel queue");
}
public void TestCallbackBackground(bool stronglyTyped)
{
var width = 640;
var height = 480;
var encoder_specification = new VTVideoEncoderSpecification();
var source_attributes = new CVPixelBufferAttributes(CVPixelFormatType.CV420YpCbCr8BiPlanarFullRange, width, height);
var duration = new CMTime(40, 1);
VTStatus status;
using var frameProperties = new NSDictionary();
int callbackCounter = 0;
var failures = new List <string> ();
var callback = new VTCompressionSession.VTCompressionOutputCallback((IntPtr sourceFrame, VTStatus status, VTEncodeInfoFlags flags, CMSampleBuffer buffer) =>
{
Interlocked.Increment(ref callbackCounter);
if (status != VTStatus.Ok)
{
failures.Add($"Callback #{callbackCounter} failed. Expected status = Ok, got status = {status}");
}
#if !NET
// Work around a crash that occur if the buffer isn't retained
if (stronglyTyped)
{
CFRetain(buffer.Handle);
}
#endif
});
using var session = stronglyTyped
? VTCompressionSession.Create(
width, height,
CMVideoCodecType.H264,
callback,
encoder_specification,
source_attributes
)
: VTCompressionSession.Create(
width, height,
CMVideoCodecType.H264,
callback,
encoder_specification,
source_attributes.Dictionary
);
var frameCount = 20;
for (var i = 0; i < frameCount; i++)
{
using var imageBuffer = new CVPixelBuffer(width, height, CVPixelFormatType.CV420YpCbCr8BiPlanarFullRange);
var pts = new CMTime(40 * i, 1);
status = session.EncodeFrame(imageBuffer, pts, duration, null, imageBuffer, out var infoFlags);
Assert.AreEqual(status, VTStatus.Ok, $"status #{i}");
// This looks weird, but it seems the video encoder can become overwhelmed otherwise, and it
// will start failing (and taking a long time to do so, eventually timing out the test).
Thread.Sleep(10);
}
;
status = session.CompleteFrames(new CMTime(40 * frameCount, 1));
Assert.AreEqual(status, VTStatus.Ok, "status finished");
Assert.AreEqual(callbackCounter, frameCount, "frame count");
Assert.That(failures, Is.Empty, "no callback failures");
}