public SKBitmap ImageBufferToSKBitmap(IImageBuffer imageBuffer)
{
if (imageBuffer == null)
{
return(null);
}
imageBuffer = imageBuffer.ToU8();
SKBitmap bitmap = null;
SKColorSpace colorSpace = null;
if (imageBuffer.Format.ColorSpace == ColorSpace.Srgb)
{
colorSpace = SKColorSpace.CreateSrgb();
}
else if (imageBuffer.Format.ColorSpace == ColorSpace.LinearRgb)
{
colorSpace = SKColorSpace.CreateSrgbLinear();
}
try
{
// for RGBA-images
if (imageBuffer.Format.PixelType == PixelType.U8C3)
{
// convert to 32bpp
var src = imageBuffer is I <byte>?((I <byte>)imageBuffer).Data.Buffer : imageBuffer.ToByteArray();
var dst = new byte[imageBuffer.Height * imageBuffer.Width * 4];
int i = 0, j = 0;
while (i < dst.Length)
{
dst[i + 0] = src[j + 0];
dst[i + 1] = src[j + 1];
dst[i + 2] = src[j + 2];
dst[i + 3] = 0xff;
i += 4;
j += 3;
}
SKColorType colorType = SKColorType.Rgba8888;
switch (imageBuffer.Format.PixelChannels)
{
case PixelChannels.Rgb:
colorType = SKColorType.Rgba8888;
break;
case PixelChannels.Bgra:
colorType = SKColorType.Bgra8888;
break;
}
using (var pinnedImage = new Utilities.PinnedGCHandle(dst))
{
var sourceInfo = new SKImageInfo(imageBuffer.Width, imageBuffer.Height, colorType, SKAlphaType.Opaque);
if (colorSpace != null)
{
sourceInfo.ColorSpace = colorSpace;
}
bitmap = new SKBitmap();
Debug.Assert(sourceInfo.RowBytes == imageBuffer.Width * 4);
if (!bitmap.InstallPixels(sourceInfo, pinnedImage.Pointer))
{
throw new Exception("InstallPixels poperation of Skia bitmap failed.");
}
}
}
// for RGBA-images
else if (imageBuffer.Format.PixelType == PixelType.U8C4)
{
// try direct copy
using (var pinnedImage = imageBuffer.Pin())
{
SKAlphaType alphaType = SKAlphaType.Unknown;
SKColorType colorType = SKColorType.Rgba8888;
switch (imageBuffer.Format.PixelChannels)
{
case PixelChannels.Rgbx:
alphaType = SKAlphaType.Opaque;
colorType = SKColorType.Rgba8888;
break;
case PixelChannels.Rgba:
alphaType = SKAlphaType.Unpremul;
colorType = SKColorType.Rgba8888;
break;
case PixelChannels.Bgrx:
alphaType = SKAlphaType.Opaque;
colorType = SKColorType.Bgra8888;
break;
case PixelChannels.Bgra:
alphaType = SKAlphaType.Unpremul;
colorType = SKColorType.Bgra8888;
break;
}
var sourceInfo = new SKImageInfo(imageBuffer.Width, imageBuffer.Height, colorType, alphaType);
Debug.Assert(sourceInfo.RowBytes == imageBuffer.Width * 4);
if (colorSpace != null)
{
sourceInfo.ColorSpace = colorSpace;
}
bitmap = new SKBitmap();
if (!bitmap.InstallPixels(sourceInfo, pinnedImage.Pointer))
{
throw new Exception("InstallPixels poperation of Skia bitmap failed.");
}
}
}
// for gray-scale
else if (imageBuffer.Format.PixelType == PixelType.U8C1)
{
// try direct copy
using (var pinnedImage = imageBuffer.Pin())
{
var sourceInfo = new SKImageInfo(imageBuffer.Width, imageBuffer.Height, SKColorType.Gray8);
Debug.Assert(sourceInfo.RowBytes == imageBuffer.Width);
bitmap = new SKBitmap();
if (!bitmap.InstallPixels(sourceInfo, pinnedImage.Pointer))
{
throw new Exception("InstallPixels poperation of Skia bitmap failed.");
}
}
}
else
{
throw new Exception("PixelFormat not yet implemented for preview image.");
}
SKBitmap result = bitmap;
bitmap = null;
colorSpace = null;
return(result);
}
finally
{
if (bitmap != null)
{
bitmap.Dispose();
if (colorSpace != null)
{
colorSpace.Dispose();
}
}
}
}
