// 怀旧效果函数
public static Bitmap changeToOld(Bitmap bitmap) {

int width = bitmap.getWidth();
int height = bitmap.getHeight();
Log.i("OldFilter", "width=" + width + "; height=" + height);
Bitmap returnBitmap = Bitmap.createBitmap(width, height,
Bitmap.Config.RGB_565);
int pixColor = 0;
int pixR = 0;
int pixG = 0;
int pixB = 0;
int newR = 0;
int newG = 0;
int newB = 0;
int[] pixels = new int[width * height];
bitmap.getPixels(pixels, 0, width, 0, 0, width, height);
for (int i = 0; i < height; i++) {
for (int k = 0; k < width; k++) {
pixColor = pixels[width * i + k];
pixR = Color.red(pixColor);
pixG = Color.green(pixColor);
pixB = Color.blue(pixColor);
newR = (int) (0.393 * pixR + 0.769 * pixG + 0.189 * pixB);
newG = (int) (0.349 * pixR + 0.686 * pixG + 0.168 * pixB);
newB = (int) (0.272 * pixR + 0.534 * pixG + 0.131 * pixB);
int newColor = Color.argb(255, newR > 255 ? 255 : newR,
newG > 255 ? 255 : newG, newB > 255 ? 255 : newB);
pixels[width * i + k] = newColor;
}
}

returnBitmap.setPixels(pixels, 0, width, 0, 0, width, height);
return returnBitmap;
}