BitmapUtils.java

package org.rocko.demos.colorfilter;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.support.v8.renderscript.Allocation;
import android.support.v8.renderscript.Element;
import android.support.v8.renderscript.RenderScript;
import android.support.v8.renderscript.ScriptIntrinsicBlur;

/**
 * Copy from my AndroidUtils project.
 * Created by Rocko on 2015/3/2 19:36
 */
public class BitmapUtils {

    public static Bitmap blurBitmap(Context applicationContext, Bitmap bitmap, float radius) {

        //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(), Bitmap.Config.ARGB_8888);

        //Instantiate a new Renderscript
        RenderScript rs = RenderScript.create(applicationContext);

        //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(radius);
        //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;
    }

    public static Bitmap drawable2Bitmap(Drawable drawable, int... defaultWH) {
        if (drawable == null)
            return null;
        if (drawable instanceof BitmapDrawable)
            return ((BitmapDrawable) drawable).getBitmap();
        try {
            Bitmap bitmap;
            if (drawable instanceof ColorDrawable)
                bitmap = Bitmap.createBitmap(defaultWH[0], defaultWH[1], Bitmap.Config.ARGB_8888);
            else
                bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(),
                        Bitmap.Config.ARGB_8888);

            Canvas canvas = new Canvas(bitmap);
            drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
            drawable.draw(canvas);
            return bitmap;
        } catch (OutOfMemoryError e) {
            e.printStackTrace();
            return null;
        }
    }

}