Adds BitmapUtil for dealing with hardware buffer wrapped bitmaps.

/*

 * Copyright (C) 2020 The Android Open Source Project

 *

 * 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.android.systemui.shared.recents.utilities;

import android.graphics.Bitmap;

import android.graphics.ColorSpace;

import android.graphics.ParcelableColorSpace;

import android.hardware.HardwareBuffer;

import android.os.Bundle;

import java.util.Objects;

/**

 * Utils for working with Bitmaps.

 */

public final class BitmapUtil {

    private static final String KEY_BUFFER = "bitmap_util_buffer";

    private static final String KEY_COLOR_SPACE = "bitmap_util_color_space";

    private BitmapUtil(){ }

    /**

     * Creates a Bundle that represents the given Bitmap.

     * <p>The Bundle will contain a wrapped version of the Bitmaps HardwareBuffer, so will avoid

     * copies when passing across processes, only pass to processes you trust.

     *

     * <p>Returns a new Bundle rather than modifying an exiting one to avoid key collisions, the

     * returned Bundle should be treated as a standalone object.

     *

     * @param bitmap to convert to bundle

     * @return a Bundle representing the bitmap, should only be parsed by

     *         {@link #bundleToHardwareBitmap(Bundle)}

     */

    public static Bundle hardwareBitmapToBundle(Bitmap bitmap) {

        if (bitmap.getConfig() != Bitmap.Config.HARDWARE) {

            throw new IllegalArgumentException(

                    "Passed bitmap must have hardware config, found: " + bitmap.getConfig());

        }

        // Bitmap assumes SRGB for null color space

        ParcelableColorSpace colorSpace =

                bitmap.getColorSpace() == null

                        ? new ParcelableColorSpace(ColorSpace.get(ColorSpace.Named.SRGB))

                        : new ParcelableColorSpace(bitmap.getColorSpace());

        Bundle bundle = new Bundle();

        bundle.putParcelable(KEY_BUFFER, bitmap.getHardwareBuffer());

        bundle.putParcelable(KEY_COLOR_SPACE, colorSpace);

        return bundle;

    }

    /**

     * Extracts the Bitmap added to a Bundle with {@link #hardwareBitmapToBundle(Bitmap)} .}

     *

     * <p>This Bitmap contains the HardwareBuffer from the original caller, be careful passing this

     * Bitmap on to any other source.

     *

     * @param bundle containing the bitmap

     * @return a hardware Bitmap

     */

    public static Bitmap bundleToHardwareBitmap(Bundle bundle) {

        if (!bundle.containsKey(KEY_BUFFER) || !bundle.containsKey(KEY_COLOR_SPACE)) {

            throw new IllegalArgumentException("Bundle does not contain a hardware bitmap");

        }

        HardwareBuffer buffer = bundle.getParcelable(KEY_BUFFER);

        ParcelableColorSpace colorSpace = bundle.getParcelable(KEY_COLOR_SPACE);

        return Bitmap.wrapHardwareBuffer(Objects.requireNonNull(buffer), colorSpace);

    }

}