public static BitmapSource SubSampleSmooth(BitmapSource bmp, int fac)
{
BitmapSource retVal = null;
int iWidth = (int)bmp.PixelWidth;
int iHeight = (int)bmp.PixelHeight;
int factor = fac;
int tWidth = iWidth / factor;
int tHeight = iHeight / factor;
int bpp = ((bmp.Format.BitsPerPixel + 7) / 8);
int iStride = iWidth * bpp;
int tStride = iStride / factor;
int dpi = 96;
byte[] imgBuffer = WpfImgUtilsEncoding.GetEncodedImageData(bmp);
byte[] thumbnailBuffer = new byte[tWidth * tHeight * bpp];
WriteableBitmap bs = new WriteableBitmap(iWidth, iHeight, dpi, dpi, bmp.Format, null);
bs.WritePixels(new Int32Rect(0, 0, iWidth, iHeight),
imgBuffer, iWidth * bpp, 0, 0);
//bs = WpfImgUtilsTransform.Resize(bmp, bmp.PixelWidth / factor, bmp.PixelHeight / factor, Interpolation.Bilinear);
//retVal = bs;
retVal = new TransformedBitmap(bs, new ScaleTransform(1.0 / factor, 1.0 / factor));
bs.Freeze();
return(retVal);
}
public static BitmapSource SubSample(BitmapSource bmp, int fac)
{
BitmapSource retVal = null;
int iWidth = (int)bmp.PixelWidth;
int iHeight = (int)bmp.PixelHeight;
int factor = fac;
int tWidth = iWidth / factor;
int tHeight = iHeight / factor;
int bpp = ((bmp.Format.BitsPerPixel + 7) / 8);
int iStride = iWidth * bpp;
int tStride = iStride / factor;
int dpi = 96;
byte[] imgBuffer = WpfImgUtilsEncoding.GetEncodedImageData(bmp);
byte[] thumbnailBuffer = new byte[tWidth * tHeight * bpp];
int imgBufferOff = 0, thumbnailBufferOff = 0;
//subsample image (same code as RSA)
for (int i = 0; i < tHeight; i++)
{
for (int j = 0; j < tWidth * bpp; j += bpp)
{
if (bpp > 0)
{
thumbnailBuffer[thumbnailBufferOff + j] = imgBuffer[imgBufferOff + j * factor];
if (bpp > 1)
{
thumbnailBuffer[thumbnailBufferOff + j + 1] = imgBuffer[imgBufferOff + j * factor + 1];
if (bpp > 2)
{
thumbnailBuffer[thumbnailBufferOff + j + 2] = imgBuffer[imgBufferOff + j * factor + 2];
if (bpp > 3)
{
thumbnailBuffer[thumbnailBufferOff + j + 3] = imgBuffer[imgBufferOff + j * factor + 3];
}
}
}
}
}
imgBufferOff += iWidth * factor * bpp;
thumbnailBufferOff += tWidth * bpp;
}
//for (int i = 0; i < tWidth; i++)
//{
// for (int j = 0; j < tHeight * bpp; j++)
// {
// int srcOff = imgBufferOff + j * factor * bpp;
// int dstOff = thumbnailBufferOff + j * bpp;
// if (srcOff + bpp < imgBuffer.Length && dstOff + bpp < thumbnailBuffer.Length)
// {
// Buffer.BlockCopy(imgBuffer, srcOff, thumbnailBuffer, dstOff, bpp);
// }
// }
// imgBufferOff += iWidth * bpp * factor;
// thumbnailBufferOff += tWidth * bpp;
//}
WriteableBitmap bs = new WriteableBitmap(tWidth, tHeight, dpi, dpi, bmp.Format, null);
bs.WritePixels(new Int32Rect(0, 0, tWidth, tHeight),
thumbnailBuffer, tWidth * bpp, 0, 0);
bs.Freeze();
retVal = bs;
return(retVal);
}