那个时代彩色的书籍是很少的,连环画几乎都是黑白色的,而且有些发黄的年代感,这个也就是它的主要特点;还有一个特点就是,画面对比鲜明;针对这两点,我们可以实现了。
private Bitmap FilterProcess(Bitmap a)
{
Bitmap srcBitmap = new Bitmap(a);
int w = srcBitmap.Width;
int h = srcBitmap.Height;
System.Drawing.Imaging.BitmapData srcData = srcBitmap.LockBits(new Rectangle(0, 0, w, h), System.Drawing.Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
byte* pSrc = (byte*)srcData.Scan0;
int offset = srcData.Stride - w * 4;
int red = 0, green = 0, blue = 0, gray = 0;
for (int j = 0; j < h; j++)
{
for (int i = 0; i < w; i++)
{
blue = (Math.Abs(pSrc[0] - pSrc[1] + pSrc[0] + pSrc[2]) * pSrc[1]) >> 8;
green = (Math.Abs(pSrc[0] - pSrc[1] + pSrc[0] + pSrc[2]) * pSrc[2]) >> 8;
red = (Math.Abs(pSrc[1] - pSrc[0] + pSrc[1] + pSrc[2]) * pSrc[2]) >> 8;
blue = Math.Max(0, Math.Min(blue, 255));
green = Math.Max(0, Math.Min(green, 255));
red = Math.Max(0, Math.Min(red, 255));
gray = (blue + green + red) / 3;
red = Math.Min(255, gray + 10);
pSrc[0] = (byte)gray;
pSrc[1] = (byte)red;
pSrc[2] = (byte)red;
pSrc += 4;
}
pSrc += offset;
}
srcBitmap.UnlockBits(srcData);
return srcBitmap;
}
效果图如下: