async Task <byte[]> GetFrameData(MediaFrameReference frame)
{
byte[] bytes = null;
if (frame == null)
{
return(bytes);
}
VideoMediaFrame videoMediaFrame = frame.VideoMediaFrame;
if (videoMediaFrame == null)
{
return(bytes);
}
VideoFrame videoFrame = videoMediaFrame.GetVideoFrame();
SoftwareBitmap softwareBitmap = videoFrame.SoftwareBitmap;
if (softwareBitmap == null)
{
return(bytes);
}
SoftwareBitmap bitmapBGRA8 = SoftwareBitmap.Convert(softwareBitmap, BitmapPixelFormat.Bgra8, BitmapAlphaMode.Ignore);
using (InMemoryRandomAccessStream stream = new InMemoryRandomAccessStream())
{
BitmapEncoder encoder = await BitmapEncoder.CreateAsync(BitmapEncoder.JpegEncoderId, stream);
// Set the software bitmap
encoder.SetSoftwareBitmap(bitmapBGRA8);
encoder.IsThumbnailGenerated = false;
try
{
await encoder.FlushAsync();
bytes = new byte[stream.Size];
await stream.AsStream().ReadAsync(bytes, 0, bytes.Length);
}
catch (Exception e)
{
Debug.WriteLine($"Error while trying to encode frame into a byte array, expceiton {e.Message}");
}
}
return(bytes);
}
public void ProcessFrame()
{
MediaFrameReference frame = videoFrameProcessor.GetLatestFrame();
VideoMediaFrame videoMediaFrame = frame?.VideoMediaFrame;
if (videoMediaFrame == null)
{
return;
}
// Validate that the incoming frame format is compatible with the FaceTracker
bool isBitmapPixelFormatSupported = videoMediaFrame.SoftwareBitmap != null && FaceTracker.IsBitmapPixelFormatSupported(videoMediaFrame.SoftwareBitmap.BitmapPixelFormat);
if (!isBitmapPixelFormatSupported)
{
return;
}
// Ask the FaceTracker to process this frame asynchronously
IAsyncOperation <IList <DetectedFace> > processFrameTask = faceTracker.ProcessNextFrameAsync(videoMediaFrame.GetVideoFrame());
try
{
IList <DetectedFace> faces = processFrameTask.GetResults();
lock (@lock)
{
if (faces.Count == 0)
{
++numFramesWithoutFaces;
// The FaceTracker might lose track of faces for a few frames, for example,
// if the person momentarily turns their head away from the videoFrameProcessor. To smooth out
// the tracking, we allow 30 video frames (~1 second) without faces before
// we say that we're no longer tracking any faces.
if (numFramesWithoutFaces > 30 && latestFaces.Any())
{
latestFaces.Clear();
}
}
else
{
numFramesWithoutFaces = 0;
latestFaces.Clear();
foreach (var face in faces)
{
latestFaces.Add(face.FaceBox);
}
}
}
}
catch (Exception e)
{
// The task might be cancelled if the FaceAnalysis failed.
Debug.LogException(e);
}
}
