PrintHelperKitkat.java 文件源码

private Bitmap convertBitmapForColorMode(Bitmap original, int colorMode) {
    if (colorMode != COLOR_MODE_MONOCHROME) {
        return original;
    }
    // Create a grayscale bitmap
    Bitmap grayscale = Bitmap.createBitmap(original.getWidth(), original.getHeight(),
            Config.ARGB_8888);
    Canvas c = new Canvas(grayscale);
    Paint p = new Paint();
    ColorMatrix cm = new ColorMatrix();
    cm.setSaturation(0);
    ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
    p.setColorFilter(f);
    c.drawBitmap(original, 0, 0, p);
    c.setBitmap(null);

    return grayscale;
}