private Bitmap DecodeImage(IProgressContext progress = null)
{
if (_decodedImage != null)
{
return(_decodedImage);
}
Func <Bitmap> decodeImageAction;
if (IsIndexed)
{
var transcoder = CreateImageConfiguration(ImageFormat, PaletteFormat)
.Transcode.With(_encodingDefinition.GetIndexEncoding(ImageFormat).IndexEncoding)
.TranscodePalette.With(_encodingDefinition.GetPaletteEncoding(PaletteFormat))
.Build();
decodeImageAction = () => transcoder.Decode(ImageInfo.ImageData, ImageInfo.PaletteData, ImageInfo.ImageSize, progress);
}
else
{
var transcoder = CreateImageConfiguration(ImageFormat, PaletteFormat)
.Transcode.With(_encodingDefinition.GetColorEncoding(ImageFormat))
.Build();
decodeImageAction = () => transcoder.Decode(ImageInfo.ImageData, ImageInfo.ImageSize, progress);
}
ExecuteActionWithProgress(() => _decodedImage = decodeImageAction(), progress);
_bestImage ??= _decodedImage;
return(_decodedImage);
}
private void AssertImageFormatExists(int imageFormat)
{
if (EncodingDefinition.GetColorEncoding(imageFormat) == null &&
EncodingDefinition.GetIndexEncoding(imageFormat) == null)
{
throw new InvalidOperationException($"The image format '{imageFormat}' is not supported by the plugin.");
}
}
private (IList <byte[]> imageData, byte[] paletteData) EncodeImage(Bitmap image, int imageFormat, int paletteFormat = -1,
IProgressContext progress = null)
{
// Create transcoder
IImageTranscoder transcoder;
if (IsIndexEncoding(imageFormat))
{
var indexEncoding = EncodingDefinition.GetIndexEncoding(imageFormat).IndexEncoding;
transcoder = CreateImageConfiguration(ImageFormat, PaletteFormat)
.ConfigureQuantization(options => options.WithColorCount(indexEncoding.MaxColors))
.Transcode.With(indexEncoding)
.TranscodePalette.With(EncodingDefinition.GetPaletteEncoding(paletteFormat))
.Build();
}
else
{
transcoder = CreateImageConfiguration(ImageFormat, PaletteFormat)
.Transcode.With(EncodingDefinition.GetColorEncoding(imageFormat))
.Build();
}
byte[] mainImageData = null;
byte[] mainPaletteData = null;
ExecuteActionWithProgress(() => (mainImageData, mainPaletteData) = transcoder.Encode(image, progress), progress);
var imageData = new byte[ImageInfo.MipMapCount + 1][];
imageData[0] = mainImageData;
// Decode palette if present, only when mip maps are needed
IList <Color> decodedPalette = null;
if (mainPaletteData != null && ImageInfo.MipMapCount > 0)
{
decodedPalette = DecodePalette(mainPaletteData);
}
// Encode mip maps
var(width, height) = (image.Width / 2, image.Height / 2);
for (var i = 0; i < ImageInfo.MipMapCount; i++)
{
imageData[i + 1] = EncodeMipMap(ResizeImage(image, width, height), imageFormat, decodedPalette);
width /= 2;
height /= 2;
}
return(imageData, mainPaletteData);
}
// TODO: Use progress
private byte[] EncodeMipMap(Bitmap mipMap, int imageFormat, IList <Color> palette = null)
{
IImageTranscoder transcoder;
if (IsIndexEncoding(imageFormat))
{
var indexEncoding = EncodingDefinition.GetIndexEncoding(imageFormat).IndexEncoding;
transcoder = CreateImageConfiguration(ImageFormat, PaletteFormat)
.ConfigureQuantization(options => options.WithColorCount(indexEncoding.MaxColors).WithPalette(() => palette))
.Transcode.With(indexEncoding)
.Build();
}
else
{
transcoder = CreateImageConfiguration(ImageFormat, PaletteFormat)
.Transcode.With(EncodingDefinition.GetColorEncoding(imageFormat))
.Build();
}
return(transcoder.Encode(mipMap).imageData);
}