/**

     * 使用Matrix将Bitmap压缩到指定大小

     * @param bitmap

     * @param w

     * @param h

     * @return

     */

    public static Bitmap resizeBitmap(Bitmap bitmap, int w, int h)

    {

        int width = bitmap.getWidth();

        int height = bitmap.getHeight();

        float scaleWidth = ((float) w) / width;

        float scaleHeight = ((float) h) / height;

        Matrix matrix = new Matrix();

        matrix.postScale(scaleWidth, scaleHeight);

        Bitmap resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0, width,

                height, matrix, true);

        return resizedBitmap;

    }

    /**

     * 给Bitmap设置圆角

     * @param bitmap

     * @param roundPx  圆角值

     * @return

     */

    public static Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){

        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap

                .getHeight(), Bitmap.Config.ARGB_8888);

        Canvas canvas = new Canvas(output);

        final int color = 0xff424242;

        final Paint paint = new Paint();

        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());

        final RectF rectF = new RectF(rect);

        paint.setAntiAlias(true);

        canvas.drawARGB(0, 0, 0, 0);

        paint.setColor(color);

        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);

        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));

        canvas.drawBitmap(bitmap, rect, rect, paint);

        return output;

    }

    /**

     * 得到圆形图片

     * @param bitmap

     * @return

     */

    public static Bitmap getOvalBitmap(Bitmap bitmap){

        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap

                .getHeight(), Bitmap.Config.ARGB_8888);

        Canvas canvas = new Canvas(output);

        final int color = 0xff424242;

        final Paint paint = new Paint();

        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());

        final RectF rectF = new RectF(rect);

        paint.setAntiAlias(true);

        canvas.drawARGB(0, 0, 0, 0);

        paint.setColor(color);

        canvas.drawOval(rectF, paint);

        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));

        canvas.drawBitmap(bitmap, rect, rect, paint);

        return output;

    }