/** 

* 处理图片的工具类.

* 
*/
public class ImageTools {

/***//**

* 图片去色,返回灰度图片

* @param bmpOriginal 传入的图片

* @return 去色后的图片
*/
public static Bitmap toGrayscale(Bitmap bmpOriginal) {
int width, height;

height = bmpOriginal.getHeight();

width = bmpOriginal.getWidth();    


Bitmap bmpGrayscale = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);

Canvas c = new Canvas(bmpGrayscale);

Paint paint = new Paint();

ColorMatrix cm = new ColorMatrix();

cm.setSaturation(0);

ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);

paint.setColorFilter(f);

c.drawBitmap(bmpOriginal, 0, 0, paint);
return bmpGrayscale;

}


/***//**

* 去色同时加圆角

* @param bmpOriginal 原图

* @param pixels 圆角弧度

* @return 修改后的图片
*/
public static Bitmap toGrayscale(Bitmap bmpOriginal, int pixels) {
return toRoundCorner(toGrayscale(bmpOriginal), pixels);

}

/***//**

* 把图片变成圆角

* @param bitmap 需要修改的图片

* @param pixels 圆角的弧度

* @return 圆角图片
*/
public static Bitmap toRoundCorner(Bitmap bitmap, int pixels) {


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

.getHeight(), 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);
final float roundPx = pixels;


paint.setAntiAlias(true);

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

paint.setColor(color);

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


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

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

return output;

}


/***//**

* 使圆角功能支持BitampDrawable

* @param bitmapDrawable 

* @param pixels 

* @return
*/
public static BitmapDrawable toRoundCorner(BitmapDrawable bitmapDrawable, int pixels) {

Bitmap bitmap = bitmapDrawable.getBitmap();

bitmapDrawable = new BitmapDrawable(toRoundCorner(bitmap, pixels));
return bitmapDrawable;

}

}