CVPixelBuffer newRenderedPixelBufferForRequest(AVAsynchronousVideoCompositionRequest request, out NSError error)
{
CVPixelBuffer dstPixels = null;
float tweenFactor = (float)factorForTimeInRange(request.CompositionTime, request.VideoCompositionInstruction.TimeRange);
var currentInstruction = (CustomVideoCompositionInstruction)request.VideoCompositionInstruction;
CVPixelBuffer foregroundSourceBuffer = request.SourceFrameByTrackID(currentInstruction.ForegroundTrackID);
CVPixelBuffer backgroundSourceBuffer = request.SourceFrameByTrackID(currentInstruction.BackgroundTrackID);
dstPixels = renderContext.CreatePixelBuffer();
if (renderContextDidChange)
{
var renderSize = renderContext.Size;
var destinationSize = new SizeF(dstPixels.Width, dstPixels.Height);
var renderContextTransform = new CGAffineTransform(renderSize.Width / 2, 0, 0, renderSize.Height / 2, renderSize.Width / 2, renderSize.Height / 2);
var destinationTransform = new CGAffineTransform(2 / destinationSize.Width, 0, 0, 2 / destinationSize.Height, -1, -1);
var normalizedRenderTransform = CGAffineTransform.Multiply(CGAffineTransform.Multiply(renderContextTransform, renderContext.RenderTransform), destinationTransform);
oglRender.RenderTransform = normalizedRenderTransform;
renderContextDidChange = false;
}
oglRender.RenderPixelBuffer(dstPixels, foregroundSourceBuffer, backgroundSourceBuffer, tweenFactor);
error = null;
return(dstPixels);
}
public override void StartVideoCompositionRequest(AVAsynchronousVideoCompositionRequest request)
{
renderingQueue.DispatchAsync(() =>
{
// Check if all pending requests have been cancelled
if (shouldCancelAllRequests)
{
request.FinishCancelledRequest();
}
else
{
// Get the next rendererd pixel buffer
var resultPixels = NewRenderedPixelBufferForRequest(request, out NSError error);
if (resultPixels != null)
{
// The resulting pixelbuffer from OpenGL renderer is passed along to the request
request.FinishWithComposedVideoFrame(resultPixels);
resultPixels.Dispose();
resultPixels = null;
}
else
{
request.FinishWithError(error);
}
}
});
}
public override void StartVideoCompositionRequest (AVAsynchronousVideoCompositionRequest asyncVideoCompositionRequest)
{
renderingQueue.DispatchAsync (() => {
if(shouldCancelAllRequests)
asyncVideoCompositionRequest.FinishCancelledRequest();
else
{
NSError error;
CVPixelBuffer resultPixels = newRenderedPixelBufferForRequest( asyncVideoCompositionRequest, out error);
if(resultPixels != null){
asyncVideoCompositionRequest.FinishWithComposedVideoFrame(resultPixels);
resultPixels.Dispose();
}
else{
asyncVideoCompositionRequest.FinishWithError(error);
}
}
});
}
private CVPixelBuffer NewRenderedPixelBufferForRequest(AVAsynchronousVideoCompositionRequest request, out NSError error)
{
CVPixelBuffer dstPixels;
// tweenFactor indicates how far within that timeRange are we rendering this frame. This is normalized to vary between 0.0 and 1.0.
// 0.0 indicates the time at first frame in that videoComposition timeRange
// 1.0 indicates the time at last frame in that videoComposition timeRange
var tweenFactor = (float)FactorForTimeInRange(request.CompositionTime, request.VideoCompositionInstruction.TimeRange);
var currentInstruction = request.VideoCompositionInstruction as CustomVideoCompositionInstruction;
// Source pixel buffers are used as inputs while rendering the transition
var foregroundSourceBuffer = request.SourceFrameByTrackID(currentInstruction.ForegroundTrackId);
var backgroundSourceBuffer = request.SourceFrameByTrackID(currentInstruction.BackgroundTrackId);
// Destination pixel buffer into which we render the output
dstPixels = renderContext.CreatePixelBuffer();
// Recompute normalized render transform everytime the render context changes
if (renderContextDidChange)
{
// The renderTransform returned by the renderContext is in X: [0, w] and Y: [0, h] coordinate system
// But since in this sample we render using OpenGLES which has its coordinate system between [-1, 1] we compute a normalized transform
var renderSize = renderContext.Size;
var destinationSize = new CGSize(dstPixels.Width, dstPixels.Height);
var renderContextTransform = new CGAffineTransform(renderSize.Width / 2, 0, 0, renderSize.Height / 2, renderSize.Width / 2, renderSize.Height / 2);
var destinationTransform = new CGAffineTransform(2 / destinationSize.Width, 0, 0, 2 / destinationSize.Height, -1, -1);
var normalizedRenderTransform = CGAffineTransform.Multiply(CGAffineTransform.Multiply(renderContextTransform, renderContext.RenderTransform), destinationTransform);
Render.RenderTransform = normalizedRenderTransform;
renderContextDidChange = false;
}
Render.RenderPixelBuffer(dstPixels, foregroundSourceBuffer, backgroundSourceBuffer, tweenFactor);
error = null;
return(dstPixels);
}
public override void StartVideoCompositionRequest(AVAsynchronousVideoCompositionRequest asyncVideoCompositionRequest)
{
renderingQueue.DispatchAsync(() => {
if (shouldCancelAllRequests)
{
asyncVideoCompositionRequest.FinishCancelledRequest();
}
else
{
NSError error = null;
CVPixelBuffer resultPixels = newRenderedPixelBufferForRequest(asyncVideoCompositionRequest, out error);
if (resultPixels != null)
{
asyncVideoCompositionRequest.FinishWithComposedVideoFrame(resultPixels);
resultPixels.Dispose();
}
else
{
asyncVideoCompositionRequest.FinishWithError(error);
}
}
});
}
CVPixelBuffer newRenderedPixelBufferForRequest (AVAsynchronousVideoCompositionRequest request, out NSError error )
{
CVPixelBuffer dstPixels;
float tweenFactor =(float) FactorForTimeInRange (request.CompositionTime, request.VideoCompositionInstruction.TimeRange);
var currentInstruction = (CustomVideoCompositionInstruction)request.VideoCompositionInstruction;
CVPixelBuffer foregroundSourceBuffer = request.SourceFrameByTrackID (currentInstruction.ForegroundTrackID);
CVPixelBuffer backgroundSourceBuffer = request.SourceFrameByTrackID (currentInstruction.BackgroundTrackID);
dstPixels = renderContext.CreatePixelBuffer ();
if (renderContextDidChange) {
var renderSize = renderContext.Size;
var destinationSize = new CGSize (dstPixels.Width, dstPixels.Height);
var renderContextTransform = new CGAffineTransform (renderSize.Width / 2, 0, 0, renderSize.Height / 2, renderSize.Width / 2, renderSize.Height / 2);
var destinationTransform = new CGAffineTransform (2 / destinationSize.Width, 0, 0, 2 / destinationSize.Height, -1, -1);
var normalizedRenderTransform = CGAffineTransform.Multiply( CGAffineTransform.Multiply(renderContextTransform, renderContext.RenderTransform), destinationTransform);
oglRender.RenderTransform = normalizedRenderTransform;
renderContextDidChange = false;
}
oglRender.RenderPixelBuffer (dstPixels, foregroundSourceBuffer, backgroundSourceBuffer, tweenFactor);
error = null;
return dstPixels;
}
