private static BitmapDecoder GetDecoder(BitmapSource image, out GifFile gifFile)
{
gifFile = (GifFile)null;
BitmapDecoder decoder = (BitmapDecoder)null;
Stream stream = (Stream)null;
Uri result = (Uri)null;
BitmapCreateOptions createOptions = BitmapCreateOptions.None;
if (image is BitmapImage bitmapImage)
{
createOptions = bitmapImage.CreateOptions;
if (bitmapImage.StreamSource != null)
{
stream = bitmapImage.StreamSource;
}
else if (bitmapImage.UriSource != (Uri)null)
{
result = bitmapImage.UriSource;
if (bitmapImage.BaseUri != (Uri)null && !result.IsAbsoluteUri)
{
result = new Uri(bitmapImage.BaseUri, result);
}
}
}
else if (image is BitmapFrame bitmapFrame)
{
decoder = bitmapFrame.Decoder;
Uri.TryCreate(bitmapFrame.BaseUri, bitmapFrame.ToString((IFormatProvider)CultureInfo.InvariantCulture), out result);
}
if (decoder == null)
{
if (stream != null)
{
stream.Position = 0L;
decoder = BitmapDecoder.Create(stream, createOptions, BitmapCacheOption.OnLoad);
}
else if (result != (Uri)null && result.IsAbsoluteUri)
{
decoder = BitmapDecoder.Create(result, createOptions, BitmapCacheOption.OnLoad);
}
}
if (decoder is GifBitmapDecoder && !ImageBehavior.CanReadNativeMetadata(decoder))
{
if (stream != null)
{
stream.Position = 0L;
gifFile = GifFile.ReadGifFile(stream, true);
}
else
{
if (!(result != (Uri)null))
{
throw new InvalidOperationException("Can't get URI or Stream from the source. AnimatedSource should be either a BitmapImage, or a BitmapFrame constructed from a URI.");
}
gifFile = ImageBehavior.DecodeGifFile(result);
}
}
if (decoder == null)
{
throw new InvalidOperationException("Can't get a decoder from the source. AnimatedSource should be either a BitmapImage or a BitmapFrame.");
}
return(decoder);
}