public static VTCompressionSession Create(int width, int height, CMVideoCodecType codecType,
VTCompressionOutputCallback compressionOutputCallback,
VTVideoEncoderSpecification encoderSpecification = null, // hardware acceleration is default behavior on iOS. no opt-in required.
NSDictionary sourceImageBufferAttributes = null)
{
return(Create(width, height, codecType, compressionOutputCallback, encoderSpecification, sourceImageBufferAttributes, static_newCompressionOutputCallback));
}
public static VTCompressionSession Create(int width, int height, CMVideoCodecType codecType,
VTVideoEncoderSpecification encoderSpecification = null,
NSDictionary sourceImageBufferAttributes = null)
{
return(Create(width, height, codecType, null,
encoderSpecification, sourceImageBufferAttributes));
}
static VTCompressionSession Create(int width, int height, CMVideoCodecType codecType,
VTCompressionOutputCallback compressionOutputCallback,
VTVideoEncoderSpecification encoderSpecification, // hardware acceleration is default behavior on iOS. no opt-in required.
NSDictionary sourceImageBufferAttributes, CompressionOutputCallback staticCback) // Undocumented options, probably always null
{
var callbackHandle = default(GCHandle);
if (compressionOutputCallback != null)
{
callbackHandle = GCHandle.Alloc(compressionOutputCallback);
}
IntPtr ret;
var result = VTCompressionSessionCreate(IntPtr.Zero, width, height, codecType,
encoderSpecification != null ? encoderSpecification.Dictionary.Handle : IntPtr.Zero,
sourceImageBufferAttributes != null ? sourceImageBufferAttributes.Handle : IntPtr.Zero,
IntPtr.Zero,
callbackHandle.IsAllocated ? (staticCback) : null,
GCHandle.ToIntPtr(callbackHandle),
out ret);
if (result == VTStatus.Ok && ret != IntPtr.Zero)
{
return new VTCompressionSession(ret, true)
{
callbackHandle = callbackHandle
}
}
;
if (callbackHandle.IsAllocated)
{
callbackHandle.Free();
}
return(null);
}
public static VTCompressionSession Create (int width, int height, CMVideoCodecType codecType,
VTCompressionOutputCallback compressionOutputCallback,
VTVideoEncoderSpecification encoderSpecification = null, // hardware acceleration is default behavior on iOS. no opt-in required.
NSDictionary sourceImageBufferAttributes = null)
{
return Create (width, height, codecType, compressionOutputCallback, encoderSpecification, sourceImageBufferAttributes, static_newCompressionOutputCallback);
}
static VTCompressionSession Create (int width, int height, CMVideoCodecType codecType,
VTCompressionOutputCallback compressionOutputCallback,
VTVideoEncoderSpecification encoderSpecification, // hardware acceleration is default behavior on iOS. no opt-in required.
NSDictionary sourceImageBufferAttributes, CompressionOutputCallback staticCback) // Undocumented options, probably always null
{
var callbackHandle = default (GCHandle);
if (compressionOutputCallback != null)
callbackHandle = GCHandle.Alloc (compressionOutputCallback);
IntPtr ret;
var result = VTCompressionSessionCreate (IntPtr.Zero, width, height, codecType,
encoderSpecification != null ? encoderSpecification.Dictionary.Handle : IntPtr.Zero,
sourceImageBufferAttributes != null ? sourceImageBufferAttributes.Handle : IntPtr.Zero,
IntPtr.Zero,
callbackHandle.IsAllocated ? (staticCback) : null,
GCHandle.ToIntPtr (callbackHandle),
out ret);
if (result == VTStatus.Ok && ret != IntPtr.Zero)
return new VTCompressionSession (ret, true) {
callbackHandle = callbackHandle
};
if (callbackHandle.IsAllocated)
callbackHandle.Free ();
return null;
}
public static VTCompressionSession Create (int width, int height, CMVideoCodecType codecType,
VTVideoEncoderSpecification encoderSpecification = null,
NSDictionary sourceImageBufferAttributes = null)
{
return Create (width, height, codecType, null,
encoderSpecification, sourceImageBufferAttributes);
}
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");
}
