/*
* Copyright (C) 2014 Pedro Vicente Gómez Sánchez.
*
* 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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.
*/
package com.github.pedrovgs.tuentitv.ui.picasso.transformation;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import com.squareup.picasso.Transformation;
import static android.graphics.Bitmap.createBitmap;
import static android.graphics.Paint.ANTI_ALIAS_FLAG;
import static android.graphics.Shader.TileMode.REPEAT;
/**
* Picasso Transformation created to apply a gray scale color effect to downloaded images.
*
* @author Pedro Vicente Gómez Sánchez <pgomez@tuenti.com>
*/
public class GrayScaleTransformation implements Transformation {
@Override public Bitmap transform(Bitmap source) {
Bitmap result = createBitmap(source.getWidth(), source.getHeight(), source.getConfig());
BitmapShader shader = new BitmapShader(result, REPEAT, REPEAT);
ColorMatrix colorMatrix = new ColorMatrix();
colorMatrix.setSaturation(0);
ColorMatrixColorFilter filter = new ColorMatrixColorFilter(colorMatrix);
Paint paint = new Paint(ANTI_ALIAS_FLAG);
paint.setColorFilter(filter);
Canvas canvas = new Canvas(result);
canvas.drawBitmap(source, 0, 0, paint);
paint.setColorFilter(null);
paint.setShader(shader);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.MULTIPLY));
canvas.drawRect(0, 0, canvas.getWidth(), canvas.getHeight(), paint);
source.recycle();
return result;
}
@Override public String key() {
return "GrayScaleTransformation";
}
}