RSBlur.java

package com.jp.wasabeef.glide.transformations.internal;

import android.annotation.TargetApi;
import android.graphics.Bitmap;
import android.os.Build;
import android.renderscript.Allocation;
import android.renderscript.Element;
import android.renderscript.RSRuntimeException;
import android.renderscript.RenderScript;
import android.renderscript.ScriptIntrinsicBlur;

import com.simplecity.amp_library.ShuttleApplication;

/**
 * Copyright (C) 2015 Wasabeef
 * <p>
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class RSBlur {

    private static RSBlur sInstance;

    private RenderScript renderScript;

    @TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR1)
    public static RSBlur getInstance() {
        if (sInstance == null) {
            sInstance = new RSBlur();
        }
        return sInstance;
    }

    private RSBlur() {
        renderScript = RenderScript.create(ShuttleApplication.getInstance());
    }

    @TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR1)
    public Bitmap blur(Bitmap bitmap, int radius) throws RSRuntimeException {

        Allocation input = null;
        Allocation output = null;
        ScriptIntrinsicBlur blur = null;
        try {
            input = Allocation.createFromBitmap(renderScript, bitmap, Allocation.MipmapControl.MIPMAP_NONE,
                    Allocation.USAGE_SCRIPT);
            output = Allocation.createTyped(renderScript, input.getType());
            blur = ScriptIntrinsicBlur.create(renderScript, Element.U8_4(renderScript));

            blur.setInput(input);
            blur.setRadius(radius);
            blur.forEach(output);
            output.copyTo(bitmap);
        } finally {
            if (input != null) {
                input.destroy();
            }
            if (output != null) {
                output.destroy();
            }
            if (blur != null) {
                blur.destroy();
            }
        }

        return bitmap;
    }
}