private async void OnJpegPacket(JpegPacket packet)
{
if (IsDecoding)
{
PendingPakcet = packet;
return;
}
IsDecoding = true;
await DecodeLiveviewFrame(packet);
IsDecoding = false;
if (Context.HistogramCreator != null && ApplicationSettings.GetInstance().IsHistogramDisplayed&& !Context.HistogramCreator.IsRunning)
{
rwLock.EnterReadLock();
try
{
Context.HistogramCreator.CreateHistogram(LiveviewImageBitmap);
}
finally
{
rwLock.ExitReadLock();
}
}
}
private async Task DecodeLiveviewFrame(JpegPacket packet, bool retry = false)
{
Action trailingTask = null;
if (LiveviewImageBitmap == null || sizeChanged)
{
await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, async() =>
{
var writeable = await LiveviewUtil.AsWriteableBitmap(packet.ImageData, Dispatcher);
OriginalLvSize = new BitmapSize {
Width = (uint)writeable.PixelWidth, Height = (uint)writeable.PixelHeight
};
var magnification = CalcLiveviewMagnification();
DebugUtil.Log(() => { return("Decode: mag: " + magnification + " offsetV: " + LvOffsetV); });
dpi = DEFAULT_DPI / magnification;
RefreshOverlayControlParams(magnification);
trailingTask = () =>
{
if (Context?.Target?.Status != null)
{
RotateLiveviewImage(Context.Target.Status.LiveviewOrientationAsDouble, (sender, arg) =>
{
RefreshOverlayControlParams(magnification);
});
}
sizeChanged = false;
};
});
}
else
{
rwLock.EnterWriteLock();
try
{
var toDelete = LiveviewImageBitmap;
trailingTask = () =>
{
// Dispose after it is drawn
toDelete?.Dispose();
};
}
finally
{
rwLock.ExitWriteLock();
}
}
using (var stream = new InMemoryRandomAccessStream())
{
await stream.WriteAsync(packet.ImageData.AsBuffer());
stream.Seek(0);
var bmp = await CanvasBitmap.LoadAsync(LiveviewImageCanvas, stream, (float)dpi);
var size = bmp.SizeInPixels;
rwLock.EnterWriteLock();
try
{
LiveviewImageBitmap = bmp;
}
finally
{
rwLock.ExitWriteLock();
}
if (!OriginalLvSize.Equals(size))
{
DisposeLiveviewImageBitmap();
if (!retry)
{
await DecodeLiveviewFrame(packet, true);
}
return;
}
}
await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
{
LiveviewImageCanvas.Invalidate();
trailingTask?.Invoke();
});
if (PendingPakcet != null)
{
var task = DecodeLiveviewFrame(PendingPakcet);
PendingPakcet = null;
}
}