/// <summary>
/// Initializes a new instance of the <see cref="GifFrameMetaData"/> class.
/// </summary>
/// <param name="other">The metadata to create an instance from.</param>
private GifFrameMetaData(GifFrameMetaData other)
{
this.ColorTableLength = other.ColorTableLength;
this.FrameDelay = other.FrameDelay;
this.DisposalMethod = other.DisposalMethod;
}
public static ObjectAnimationUsingKeyFrames CreateFrames(GifBitmapDecoder decoder)
{
if (decoder == null)
{
return(null);
}
ObjectAnimationUsingKeyFrames animation = new ObjectAnimationUsingKeyFrames();
// Read MetaData from GIF
// this give us the Width and Height of the GIF
GifMetaData gifData = GifMetaDataReader.GetGifMetaData(decoder);
if (gifData == null)
{
return(null);
}
TimeSpan animationTime = TimeSpan.FromMilliseconds(0);
BitmapSource baseFrame = null;
// create a animation for every frame in GIF
foreach (BitmapFrame curFrame in decoder.Frames)
{
// first we need to read the metadata from the frame
// to know the position, width, height, delay and disposalmethod
GifFrameMetaData frameMetaData = GifMetaDataReader.GetGifFrameMetaData(curFrame);
if (frameMetaData != null)
{
// Create a "image" from the current frame
BitmapSource CurCreatedFrame =
GifImageFrameCreator.CreateFrame(
new System.Drawing.Size(gifData.Width, gifData.Height),
curFrame, frameMetaData, baseFrame);
// add the frame to the animaton
animation.KeyFrames.Add(new DiscreteObjectKeyFrame()
{
KeyTime = animationTime,
Value = CurCreatedFrame
});
// Check the disposal method
switch (frameMetaData.DisposalMethod)
{
case GifFrameDisposalMethod.None:
break;
case GifFrameDisposalMethod.DoNotDispose:
baseFrame = CurCreatedFrame;
break;
case GifFrameDisposalMethod.RestoreBackground:
baseFrame = GifImageFrameCreator.RestoreBackground(new System.Drawing.Size(gifData.Width, gifData.Height), curFrame, frameMetaData);
break;
case GifFrameDisposalMethod.RestorePrevious:
break;
default:
break;
}
// increse the timeline with the delay of the frame
animationTime += frameMetaData.Delay;
}
}
animation.Duration = animationTime;
return(animation);
}
