在进行模糊的时候，可以先对原始图片进行压缩，然后选择一个合适的方式进行模糊。

效果如下：

模糊

1、处理图片

缩放、旋转图片

private Bitmap getBitmap(Bitmap source) {

//scaleFactor：压缩比

Bitmap tempBitmap= Bitmap.createBitmap((int) (source.getWidth() / scaleFactor), (int) blurHeight, Bitmap.Config.ARGB_8888);

Canvas canvas=new Canvas(tempBitmap);

canvas.scale(1/scaleFactor,-1*blurHeight/source.getHeight());

canvas.translate(0, -source.getHeight());

Paint paint=new Paint(Paint.ANTI_ALIAS_FLAG);

paint.setFlags(Paint.FILTER_BITMAP_FLAG);

// ColorMatrix colorMatrix=new ColorMatrix();

// colorMatrix.setScale(0.8f,0.8f,0.8f,1);

// paint.setColorFilter(new ColorMatrixColorFilter(colorMatrix));

canvas.drawBitmap(source, 0, 0, paint);

return tempBitmap;

}

2、模糊图片

1、fastblur

stackblur的java实现，这里

使用

Blur.fastblur(context,tempBitmap,25);

2、rs-stackblur

stackblur的Renderscript实现，这里

添加依赖

compile 'com.commit451:NativeStackBlur:1.0.2'

使用

NativeStackBlur.process(tempBitmap, 60);

其中，模糊半径越大，处理后的图片越模糊

**3、RenderScript ** ScriptIntrinsicBlur

RenderScript，一个强大的图片处理框架，可以使用ScriptIntrinsicBlur 实现高斯模糊的效果(API 17)。

需要进行如下配置：

defaultConfig {

......

renderscriptTargetApi 19

renderscriptSupportModeEnabled true

}

代码如下：

public Bitmap blurBitmap(Bitmap bitmap){

//Let's create an empty bitmap with the same size of the bitmap we want to blur

Bitmap outBitmap = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888);

//Instantiate a new Renderscript

RenderScript rs = RenderScript.create(getApplicationContext());

//Create an Intrinsic Blur Script using the Renderscript

ScriptIntrinsicBlur blurScript = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));

//Create the Allocations (in/out) with the Renderscript and the in/out bitmaps

Allocation allIn = Allocation.createFromBitmap(rs, bitmap);

Allocation allOut = Allocation.createFromBitmap(rs, outBitmap);

//Set the radius of the blur: 0 < radius <= 25

blurScript.setRadius(25.0f);

//Perform the Renderscript

blurScript.setInput(allIn);

blurScript.forEach(allOut);

//Copy the final bitmap created by the out Allocation to the outBitmap

allOut.copyTo(outBitmap);

//recycle the original bitmap

bitmap.recycle();

//After finishing everything, we destroy the Renderscript.

rs.destroy();

return outBitmap;

}