懷舊風格濾鏡
本文介紹一款懷舊風格濾鏡特效的代碼實現，這個濾鏡效果跟前面我們介紹的老照片濾鏡效果相比，聽起來感覺沒太大差，實際上老照片不僅 有懷舊的風格，更多了一些懷舊的痕跡，比如照片的褶皺，裂紋等等，而懷舊風格，只是一種發黃的顏色風格而已。
下面給出懷舊風格的代碼：
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 b = 0, g = 0, r = 0, gray = 0;
for (int j = 0; j < h; j++)
{
for (int i = 0; i < w; i++)
{
b = pSrc[0];
g = pSrc[1];
r = pSrc[2];
gray = (272 * r + 534 * g + 131 * b) / 1000;
pSrc[0] = (byte)(Math.Min(255, Math.Max(0, gray)));
gray = (349 * r + 686 * g + 168 * b) / 1000;
pSrc[1] = (byte)(Math.Min(255, Math.Max(0, gray)));
gray = (393 * r + 769 * g + 189 * b) / 1000;
pSrc[2] = (byte)(Math.Min(255, Math.Max(0, gray)));
pSrc += 4;
}
pSrc += offset;
}
srcBitmap.UnlockBits(srcData);
return srcBitmap;
}
代碼很短，也很簡單，效果卻還 不錯，下面看下效果：
