private static CompressedBitmapSource ClearArea(CompressedBitmapSource compFrame, FrameMetadata metadata)
{
BitmapSource frame = compFrame;
DrawingVisual visual = new DrawingVisual();
using (var context = visual.RenderOpen())
{
var fullRect = new Rect(0, 0, frame.PixelWidth, frame.PixelHeight);
var clearRect = new Rect(metadata.Left, metadata.Top, metadata.Width, metadata.Height);
var clip = Geometry.Combine(
new RectangleGeometry(fullRect),
new RectangleGeometry(clearRect),
GeometryCombineMode.Exclude,
null);
context.PushClip(clip);
context.DrawImage(frame, fullRect);
}
var bitmap = new RenderTargetBitmap(
frame.PixelWidth, frame.PixelHeight,
frame.DpiX, frame.DpiY,
PixelFormats.Pbgra32);
bitmap.Render(visual);
//if (bitmap.CanFreeze && !bitmap.IsFrozen)
// bitmap.Freeze();
var result = new CompressedBitmapSource(bitmap);
bitmap = null;
return(result);
}
private static CompressedBitmapSource MakeFrame(
Int32Size fullSize,
CompressedBitmapSource rawFrame, FrameMetadata metadata,
CompressedBitmapSource baseFrame)
{
if (baseFrame == null && IsFullFrame(metadata, fullSize))
{
// No previous image to combine with, and same size as the full image
// Just return the frame as is
return(rawFrame);
}
WriteableBitmap bitmap;
if (baseFrame == null)
{
bitmap = new WriteableBitmap(fullSize.Width, fullSize.Height, 96, 96, PixelFormats.Pbgra32, null);
}
else
{
bitmap = new WriteableBitmap(baseFrame);
}
var rawBitmap = new WriteableBitmap(rawFrame);
bitmap.Blit(new Rect(metadata.Left, metadata.Top, metadata.Width, metadata.Height), rawBitmap, new Rect(0, 0, rawFrame.Width, rawFrame.Height));
var result = new CompressedBitmapSource((BitmapSource)bitmap);
bitmap = null;
rawBitmap = null;
GC.Collect();
Dispatcher.CurrentDispatcher.Invoke(() => {}, DispatcherPriority.ContextIdle);
return(result);
}
private static ObjectAnimationUsingKeyFrames GetAnimation(Image imageControl, BitmapSource source)
{
var animation = AnimationCache.GetAnimation(source, GetRepeatBehavior(imageControl));
if (animation != null)
{
return(animation);
}
GifFile gifMetadata;
var decoder = GetDecoder(source, out gifMetadata) as GifBitmapDecoder;
if (decoder != null && decoder.Frames.Count > 1)
{
var fullSize = GetFullSize(decoder, gifMetadata);
int index = 0;
animation = new ObjectAnimationUsingKeyFrames();
var totalDuration = TimeSpan.Zero;
CompressedBitmapSource baseFrame = null;
foreach (var rawFrame in decoder.Frames)
{
var metadata = GetFrameMetadata(decoder, gifMetadata, index);
var result = MakeFrame(fullSize, rawFrame, metadata, baseFrame);
var frame = new CompressedBitmapSource(result);
var keyFrame = new DiscreteObjectKeyFrame(frame, totalDuration);
animation.KeyFrames.Add(keyFrame);
totalDuration += metadata.Delay;
switch (metadata.DisposalMethod)
{
case FrameDisposalMethod.None:
case FrameDisposalMethod.DoNotDispose:
baseFrame = frame;
break;
case FrameDisposalMethod.RestoreBackground:
if (IsFullFrame(metadata, fullSize))
{
baseFrame = null;
}
else
{
baseFrame = ClearArea(frame, metadata);
}
break;
case FrameDisposalMethod.RestorePrevious:
// Reuse same base frame
break;
}
index++;
}
animation.Duration = totalDuration;
animation.RepeatBehavior = GetActualRepeatBehavior(imageControl, decoder, gifMetadata);
AnimationCache.AddAnimation(source, GetRepeatBehavior(imageControl), animation);
AnimationCache.IncrementReferenceCount(source, GetRepeatBehavior(imageControl));
return(animation);
}
return(null);
}
