BlurTransform.java

package com.bdenney.scfav.image;

import android.annotation.TargetApi;
import android.app.Activity;
import android.graphics.Bitmap;
import android.os.Build;
import android.renderscript.Allocation;
import android.renderscript.Element;
import android.renderscript.RenderScript;
import android.renderscript.ScriptIntrinsicBlur;
import com.squareup.picasso.Transformation;

/**
 * {@link com.squareup.picasso.Transformation} for bluring the image using renderscript intrinsics.
 */
@TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR1)
public class BlurTransformer implements Transformation {
	/**
	 * The activity to initialize the renderscript with.
	 */
	private Activity mActivity;

	/**
	 * Constructor.
	 *
	 * @param activity
	 * 		the activity to initialize the renderscript with.
	 */
	public BlurTransformer(final Activity activity) {
		mActivity = activity;
	}

	@Override
	public String key() {
		return "intrinsicBlur()";
	}

	@Override
	public Bitmap transform(Bitmap source) {
		// Create an output bitmap by copying the source.
		final Bitmap output = source.copy(Bitmap.Config.ARGB_8888, true);

		RenderScript rs = RenderScript.create(mActivity);
		ScriptIntrinsicBlur theIntrinsic = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));
		Allocation tmpIn = Allocation.createFromBitmap(rs, source);
		Allocation tmpOut = Allocation.createFromBitmap(rs, output);
		theIntrinsic.setRadius(1.f);
		theIntrinsic.setInput(tmpIn);
		theIntrinsic.forEach(tmpOut);
		tmpOut.copyTo(output);
		source.recycle();
		return output;
	}
}