/*
 * Copyright (C) 2013 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.
 */
package com.squareup.picasso;

import android.graphics.Bitmap;

/** Image transformation. */
public interface Transformation {
  /**
   * Transform the source bitmap into a new bitmap. If you create a new bitmap instance, you must
   * call {@link android.graphics.Bitmap#recycle()} on {@code source}. You may return the original
   * if no transformation is required.
   */
  Bitmap transform(Bitmap source);

  /**
   * Returns a unique key for the transformation, used for caching purposes. If the transformation
   * has parameters (e.g. size, scale factor, etc) then these should be part of the key.
   */
  String key();
}