先上效果图：

Layout文件:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#99CC99"
    tools:context=".MainActivity" >
    
    
    <ImageView 
        android:id="@+id/img1"
        android:layout_centerInParent="true"
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:adjustViewBounds="true"
        android:scaleType="centerInside"
        android:src=http://www.mamicode.com/"@drawable/portrait">

首先介绍两种把资源里的drawable转成bitmap的方式
第一种:
Bitmap bmp=BitmapFactory.decodeResource(this.getResources(), R.drawable.portrait);
第二种:
	Drawable d = this.getResources().getDrawable(R.drawable.portrait);
		Bitmap bmp = drawableToBitmap(d);
	public static Bitmap drawableToBitmap(Drawable drawable) {       
        Bitmap bitmap = Bitmap.createBitmap(
                                        drawable.getIntrinsicWidth(),
                                        drawable.getIntrinsicHeight(),
                                        Bitmap.Config.ARGB_8888
                                                        );

        Canvas canvas = new Canvas(bitmap);
        //canvas.setBitmap(bitmap);
        drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
        drawable.draw(canvas);
        return bitmap;
}

把Bitmap加上圆角的方法:
private static RectF rrbRectf = new RectF();
	private static Path rrbRath = new Path();
	private static final int RRB_DEFAULT_SIZE = 10;
	
	public static Bitmap outputBmp(Context ctx, Bitmap src, boolean isCover) {
		Bitmap v = null;
		if (isCover) {
			v = BitmapFactory.decodeResource(ctx.getResources(), R.drawable.v);
		}else{
			v = BitmapFactory.decodeResource(ctx.getResources(), R.drawable.tv);
		}
		Bitmap bmp = null;
		int arcLength = RRB_DEFAULT_SIZE;
		if (src != null && arcLength > 0) {
			int width = src.getWidth();
			int height = src.getHeight();
			// Utils.loge("width:" + width + "height:" + height);
			Bitmap newBitmap = Bitmap.createBitmap(width, height,
					Bitmap.Config.ARGB_4444);
			Canvas canvas = new Canvas(newBitmap);
			rrbRath.reset();
			rrbRectf.set(0, 0, width, height);
			<strong>rrbRath.addRoundRect(rrbRectf, arcLength, arcLength,
					Path.Direction.CW);  //这里是加上圆角</strong>
			canvas.clipPath(rrbRath);
			canvas.drawBitmap(src, 0, 0, new Paint(Paint.ANTI_ALIAS_FLAG));
			if (newBitmap != null && v != null) {
				int width1 = newBitmap.getWidth();
				int height1 = newBitmap.getHeight();
				int width2 = v.getWidth();
				int height2 = v.getHeight();
				bmp = Bitmap.createBitmap(width1 + (width2 / 2), height1
						+ (height2 / 2), Bitmap.Config.ARGB_4444);
				bmp.eraseColor(Color.TRANSPARENT);
				Canvas canvas2 = new Canvas(bmp);
				canvas2.drawBitmap(newBitmap, 0, 0, new Paint(
						Paint.ANTI_ALIAS_FLAG));
				<strong>canvas2.drawBitmap(v, width1 - (width2 / 2), height1
						- (height2 / 2), new Paint(Paint.ANTI_ALIAS_FLAG));  //这里是在图片右下角加上v</strong>
				newBitmap.recycle();
				v.recycle();
				return bmp;
			}
			src.recycle();
		}
		return bmp;

	}