blurBitmap.java

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
		blurScript.setRadius(25.f);
		
		//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;
		
		
	}

This is a simple method you can use to apply a subtle Blur to bitmaps. This is done using Renderscript Intrinsics, a built-in function of Renderscript you can use out-of-the-box to achieve complex image manipulation like blur or matrix convolution.

More infos about Intrinsics here: http://android-developers.blogspot.it/2013/08/renderscript-intrinsics.html

But this code only allow with api level 11....

This supports API level 17 and Above.....

Hi,

I am getting two errors.

1. The method U8_4(RenderScript) is undefined for the type Element.
2. ARGB_8888 cannot be resolved or is not a field

No errors here, seems to be fine. Only checked on API23, Android Studio 2.1.1
Can this be used to blur part of an image? Like the example you show here: https://plus.google.com/+MarioViviani/posts/fhuzYkji9zz

I wonder in the future if we can use radius greater than 25. Currently use loop to handle it but the performance is not good.