/**
     * 转换成圆角
     *
     * @param bmp
     * @param roundPx
     * @return
     */
    public static Bitmap convertToRoundedCorner(Bitmap bmp, float roundPx) {

        Bitmap newBmp = Bitmap.createBitmap(bmp.getWidth(), bmp.getHeight(),
                Config.ARGB_8888);
        // 得到画布
        Canvas canvas = new Canvas(newBmp);

        final int color = 0xff424242;
        final Paint paint = new Paint();
        final Rect rect = new Rect(0, 0, bmp.getWidth(), bmp.getHeight());
        final RectF rectF = new RectF(rect);

        paint.setAntiAlias(true);
        canvas.drawARGB(0, 0, 0, 0);
        paint.setColor(color);
        // 第二个和第三个参数一样则画的是正圆的一角，否则是椭圆的一角
        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);

        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
        canvas.drawBitmap(bmp, rect, rect, paint);

        return newBmp;
    }

/**
     * 将彩色图转换为黑白图
     *
     * @param 位图
     * @return 返回转换好的位图
     */
    public static Bitmap convertToBlackWhite(Bitmap bmp) {
        int width = bmp.getWidth(); // 获取位图的宽
        int height = bmp.getHeight(); // 获取位图的高

        int[] pixels = new int[width * height]; // 通过位图的大小创建像素点数组

        bmp.getPixels(pixels, 0, width, 0, 0, width, height);
        int alpha = 0xFF > 16);
                int green = ((grey & 0x0000FF00) >> 8);
                int blue = (grey & 0x000000FF);

                grey = (int) (red * 0.3 + green * 0.59 + blue * 0.11);
                grey = alpha | (grey