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@AKiniyalocts
Created January 15, 2016 18:31
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Picasso Grayscale Transformation
/*
* Copyright (C) 2014 Square, Inc.
*
* 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.
*/
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.batterii.mobile.R;
import com.squareup.picasso.Picasso;
import com.squareup.picasso.Transformation;
import java.io.IOException;
import static android.graphics.Bitmap.createBitmap;
import static android.graphics.Paint.ANTI_ALIAS_FLAG;
import static android.graphics.Shader.TileMode.REPEAT;
public class GrayscaleTransformation implements Transformation {
private final Picasso picasso;
public GrayscaleTransformation(Picasso picasso) {
this.picasso = picasso;
}
@Override public Bitmap transform(Bitmap source) {
Bitmap result = createBitmap(source.getWidth(), source.getHeight(), source.getConfig());
Bitmap noise;
try {
noise = picasso.load(R.drawable.noise).get();
} catch (IOException e) {
throw new RuntimeException("Failed to apply transformation! Missing resource.");
}
BitmapShader shader = new BitmapShader(noise, 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();
noise.recycle();
return result;
}
@Override public String key() {
return "grayscaleTransformation()";
}
}
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