Merge "Rewrite thread logic, add tests and add color extraction for CanvasEngine" into tm-qpr-dev

packages/SystemUI/src/com/android/systemui/wallpapers/ImageWallpaper.java

@@ -16,21 +16,17 @@
 
 package com.android.systemui.wallpapers;
 
-import static android.view.Display.DEFAULT_DISPLAY;
-
 import static com.android.systemui.flags.Flags.USE_CANVAS_RENDERER;
 
 import android.app.WallpaperColors;
 import android.app.WallpaperManager;
-import android.content.ComponentCallbacks2;
-import android.content.Context;
 import android.graphics.Bitmap;
+import android.graphics.Canvas;
 import android.graphics.RecordingCanvas;
 import android.graphics.Rect;
 import android.graphics.RectF;
 import android.hardware.display.DisplayManager;
 import android.hardware.display.DisplayManager.DisplayListener;
-import android.os.AsyncTask;
 import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.SystemClock;
@@ -40,8 +36,6 @@ import android.util.ArraySet;
 import android.util.Log;
 import android.util.MathUtils;
 import android.util.Size;
-import android.view.Display;
-import android.view.DisplayInfo;
 import android.view.Surface;
 import android.view.SurfaceHolder;
 import android.view.WindowManager;
@@ -49,8 +43,11 @@ import android.view.WindowManager;
 import androidx.annotation.NonNull;
 
 import com.android.internal.annotations.VisibleForTesting;
+import com.android.systemui.dagger.qualifiers.Background;
+import com.android.systemui.dagger.qualifiers.Main;
 import com.android.systemui.flags.FeatureFlags;
-import com.android.systemui.wallpapers.canvas.ImageCanvasWallpaperRenderer;
+import com.android.systemui.util.concurrency.DelayableExecutor;
+import com.android.systemui.wallpapers.canvas.WallpaperColorExtractor;
 import com.android.systemui.wallpapers.gl.EglHelper;
 import com.android.systemui.wallpapers.gl.ImageWallpaperRenderer;
 
@@ -59,6 +56,7 @@ import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.Executor;
 
 import javax.inject.Inject;
 
@@ -78,15 +76,28 @@ public class ImageWallpaper extends WallpaperService {
     private final ArrayList<RectF> mLocalColorsToAdd = new ArrayList<>();
     private final ArraySet<RectF> mColorAreas = new ArraySet<>();
     private volatile int mPages = 1;
+    private boolean mPagesComputed = false;
     private HandlerThread mWorker;
     // scaled down version
     private Bitmap mMiniBitmap;
     private final FeatureFlags mFeatureFlags;
 
+    // used in canvasEngine to load/unload the bitmap and extract the colors
+    @Background
+    private final DelayableExecutor mBackgroundExecutor;
+    private static final int DELAY_UNLOAD_BITMAP = 2000;
+
+    @Main
+    private final Executor mMainExecutor;
+
     @Inject
-    public ImageWallpaper(FeatureFlags featureFlags) {
+    public ImageWallpaper(FeatureFlags featureFlags,
+            @Background DelayableExecutor backgroundExecutor,
+            @Main Executor mainExecutor) {
         super();
         mFeatureFlags = featureFlags;
+        mBackgroundExecutor = backgroundExecutor;
+        mMainExecutor = mainExecutor;
     }
 
     @Override
@@ -339,7 +350,6 @@ public class ImageWallpaper extends WallpaperService {
                 imgArea.left = 0;
                 imgArea.right = 1;
             }
-
             return imgArea;
         }
 
@@ -510,69 +520,84 @@ public class ImageWallpaper extends WallpaperService {
 
 
     class CanvasEngine extends WallpaperService.Engine implements DisplayListener {
-
-        // time [ms] before unloading the wallpaper after it is loaded
-        private static final int DELAY_FORGET_WALLPAPER = 5000;
-
-        private final Runnable mUnloadWallpaperCallback = this::unloadWallpaper;
-
         private WallpaperManager mWallpaperManager;
-        private ImageCanvasWallpaperRenderer mImageCanvasWallpaperRenderer;
+        private final WallpaperColorExtractor mWallpaperColorExtractor;
+        private SurfaceHolder mSurfaceHolder;
+        @VisibleForTesting
+        static final int MIN_SURFACE_WIDTH = 128;
+        @VisibleForTesting
+        static final int MIN_SURFACE_HEIGHT = 128;
         private Bitmap mBitmap;
 
-        private Display mDisplay;
+        /*
-        private final DisplayInfo mTmpDisplayInfo = new DisplayInfo();
+         * Counter to unload the bitmap as soon as possible.
-
+         * Before any bitmap operation, this is incremented.
-        private AsyncTask<Void, Void, Bitmap> mLoader;
+         * After an operation completion, this is decremented (synchronously),
-        private boolean mNeedsDrawAfterLoadingWallpaper = false;
+         * and if the count is 0, unload the bitmap
+         */
+        private int mBitmapUsages = 0;
+        private final Object mLock = new Object();
 
         CanvasEngine() {
             super();
             setFixedSizeAllowed(true);
             setShowForAllUsers(true);
-        }
+            mWallpaperColorExtractor = new WallpaperColorExtractor(
+                    mBackgroundExecutor,
+                    new WallpaperColorExtractor.WallpaperColorExtractorCallback() {
+                        @Override
+                        public void onColorsProcessed(List<RectF> regions,
+                                List<WallpaperColors> colors) {
+                            CanvasEngine.this.onColorsProcessed(regions, colors);
+                        }
 
-        void trimMemory(int level) {
+                        @Override
-            if (level >= ComponentCallbacks2.TRIM_MEMORY_RUNNING_LOW
+                        public void onMiniBitmapUpdated() {
-                    && level <= ComponentCallbacks2.TRIM_MEMORY_RUNNING_CRITICAL
+                            CanvasEngine.this.onMiniBitmapUpdated();
-                    && isBitmapLoaded()) {
+                        }
-                if (DEBUG) {
+
-                    Log.d(TAG, "trimMemory");
+                        @Override
-                }
+                        public void onActivated() {
-                unloadWallpaper();
+                            setOffsetNotificationsEnabled(true);
+                        }
+
+                        @Override
+                        public void onDeactivated() {
+                            setOffsetNotificationsEnabled(false);
+                        }
+                    });
+
+            // if the number of pages is already computed, transmit it to the color extractor
+            if (mPagesComputed) {
+                mWallpaperColorExtractor.onPageChanged(mPages);
             }
         }
 
         @Override
         public void onCreate(SurfaceHolder surfaceHolder) {
+            Trace.beginSection("ImageWallpaper.CanvasEngine#onCreate");
             if (DEBUG) {
                 Log.d(TAG, "onCreate");
             }
+            mWallpaperManager = getDisplayContext().getSystemService(WallpaperManager.class);
+            mSurfaceHolder = surfaceHolder;
+            Rect dimensions = mWallpaperManager.peekBitmapDimensions();
+            int width = Math.max(MIN_SURFACE_WIDTH, dimensions.width());
+            int height = Math.max(MIN_SURFACE_HEIGHT, dimensions.height());
+            mSurfaceHolder.setFixedSize(width, height);
 
-            mWallpaperManager = getSystemService(WallpaperManager.class);
+            getDisplayContext().getSystemService(DisplayManager.class)
-            super.onCreate(surfaceHolder);
+                    .registerDisplayListener(this, null);
-
+            getDisplaySizeAndUpdateColorExtractor();
-            final Context displayContext = getDisplayContext();
+            Trace.endSection();
-            final int displayId = displayContext == null ? DEFAULT_DISPLAY :
-                    displayContext.getDisplayId();
-            DisplayManager dm = getSystemService(DisplayManager.class);
-            if (dm != null) {
-                mDisplay = dm.getDisplay(displayId);
-                if (mDisplay == null) {
-                    Log.e(TAG, "Cannot find display! Fallback to default.");
-                    mDisplay = dm.getDisplay(DEFAULT_DISPLAY);
-                }
-            }
-            setOffsetNotificationsEnabled(false);
-
-            mImageCanvasWallpaperRenderer = new ImageCanvasWallpaperRenderer(surfaceHolder);
-            loadWallpaper(false);
         }
 
         @Override
         public void onDestroy() {
-            super.onDestroy();
+            getDisplayContext().getSystemService(DisplayManager.class)
-            unloadWallpaper();
+                    .unregisterDisplayListener(this);
+            mWallpaperColorExtractor.cleanUp();
+            unloadBitmap();
         }
 
         @Override
@@ -580,32 +605,31 @@ public class ImageWallpaper extends WallpaperService {
             return true;
         }
 
+        @Override
+        public boolean shouldWaitForEngineShown() {
+            return true;
+        }
+
         @Override
         public void onSurfaceChanged(SurfaceHolder holder, int format, int width, int height) {
             if (DEBUG) {
                 Log.d(TAG, "onSurfaceChanged: width=" + width + ", height=" + height);
             }
-            super.onSurfaceChanged(holder, format, width, height);
-            mImageCanvasWallpaperRenderer.setSurfaceHolder(holder);
-            drawFrame(false);
         }
 
         @Override
         public void onSurfaceDestroyed(SurfaceHolder holder) {
-            super.onSurfaceDestroyed(holder);
             if (DEBUG) {
                 Log.i(TAG, "onSurfaceDestroyed");
             }
-            mImageCanvasWallpaperRenderer.setSurfaceHolder(null);
+            mSurfaceHolder = null;
         }
 
         @Override
         public void onSurfaceCreated(SurfaceHolder holder) {
-            super.onSurfaceCreated(holder);
             if (DEBUG) {
                 Log.i(TAG, "onSurfaceCreated");
             }
-            mImageCanvasWallpaperRenderer.setSurfaceHolder(holder);
         }
 
         @Override
@@ -613,135 +637,88 @@ public class ImageWallpaper extends WallpaperService {
             if (DEBUG) {
                 Log.d(TAG, "onSurfaceRedrawNeeded");
             }
-            super.onSurfaceRedrawNeeded(holder);
+            drawFrame();
-            // At the end of this method we should have drawn into the surface.
+        }
-            // This means that the bitmap should be loaded synchronously if
+
-            // it was already unloaded.
+        private void drawFrame() {
-            if (!isBitmapLoaded()) {
+            mBackgroundExecutor.execute(this::drawFrameSynchronized);
-                setBitmap(mWallpaperManager.getBitmap(true /* hardware */));
+        }
+
+        private void drawFrameSynchronized() {
+            synchronized (mLock) {
+                drawFrameInternal();
             }
-            drawFrame(true);
         }
 
-        private DisplayInfo getDisplayInfo() {
+        private void drawFrameInternal() {
-            mDisplay.getDisplayInfo(mTmpDisplayInfo);
+            if (mSurfaceHolder == null) {
-            return mTmpDisplayInfo;
-        }
-
-        private void drawFrame(boolean forceRedraw) {
-            if (!mImageCanvasWallpaperRenderer.isSurfaceHolderLoaded()) {
                 Log.e(TAG, "attempt to draw a frame without a valid surface");
                 return;
             }
 
+            // load the wallpaper if not already done
             if (!isBitmapLoaded()) {
-                // ensure that we load the wallpaper.
+                loadWallpaperAndDrawFrameInternal();
-                // if the wallpaper is currently loading, this call will have no effect.
-                loadWallpaper(true);
-                return;
-            }
-            mImageCanvasWallpaperRenderer.drawFrame(mBitmap, forceRedraw);
-        }
-
-        private void setBitmap(Bitmap bitmap) {
-            if (bitmap == null) {
-                Log.e(TAG, "Attempt to set a null bitmap");
-            } else if (mBitmap == bitmap) {
-                Log.e(TAG, "The value of bitmap is the same");
-            } else if (bitmap.getWidth() < 1 || bitmap.getHeight() < 1) {
-                Log.e(TAG, "Attempt to set an invalid wallpaper of length "
-                        + bitmap.getWidth() + "x" + bitmap.getHeight());
             } else {
-                if (mBitmap != null) {
+                mBitmapUsages++;
-                    mBitmap.recycle();
+
-                }
+                // drawing is done on the main thread
-                mBitmap = bitmap;
+                mMainExecutor.execute(() -> {
+                    drawFrameOnCanvas(mBitmap);
+                    reportEngineShown(false);
+                    unloadBitmapIfNotUsed();
+                });
             }
         }
 
-        private boolean isBitmapLoaded() {
+        @VisibleForTesting
+        void drawFrameOnCanvas(Bitmap bitmap) {
+            Trace.beginSection("ImageWallpaper.CanvasEngine#drawFrame");
+            // TODO change SurfaceHolder API to add wcg support
+            Canvas c = mSurfaceHolder.lockHardwareCanvas();
+            if (c != null) {
+                Rect dest = mSurfaceHolder.getSurfaceFrame();
+                try {
+                    c.drawBitmap(bitmap, null, dest, null);
+                } finally {
+                    mSurfaceHolder.unlockCanvasAndPost(c);
+                }
+            }
+            Trace.endSection();
+        }
+
+        @VisibleForTesting
+        boolean isBitmapLoaded() {
             return mBitmap != null && !mBitmap.isRecycled();
         }
 
-        /**
+        private void unloadBitmapIfNotUsed() {
-         * Loads the wallpaper on background thread and schedules updating the surface frame,
+            mBackgroundExecutor.execute(this::unloadBitmapIfNotUsedSynchronized);
-         * and if {@code needsDraw} is set also draws a frame.
-         *
-         * If loading is already in-flight, subsequent loads are ignored (but needDraw is or-ed to
-         * the active request).
-         *
-         */
-        private void loadWallpaper(boolean needsDraw) {
-            mNeedsDrawAfterLoadingWallpaper |= needsDraw;
-            if (mLoader != null) {
-                if (DEBUG) {
-                    Log.d(TAG, "Skipping loadWallpaper, already in flight ");
-                }
-                return;
-            }
-            mLoader = new AsyncTask<Void, Void, Bitmap>() {
-                @Override
-                protected Bitmap doInBackground(Void... params) {
-                    Throwable exception;
-                    try {
-                        Bitmap wallpaper = mWallpaperManager.getBitmap(true /* hardware */);
-                        if (wallpaper != null
-                                && wallpaper.getByteCount() > RecordingCanvas.MAX_BITMAP_SIZE) {
-                            throw new RuntimeException("Wallpaper is too large to draw!");
-                        }
-                        return wallpaper;
-                    } catch (RuntimeException | OutOfMemoryError e) {
-                        exception = e;
-                    }
-
-                    if (isCancelled()) {
-                        return null;
-                    }
-
-                    // Note that if we do fail at this, and the default wallpaper can't
-                    // be loaded, we will go into a cycle.  Don't do a build where the
-                    // default wallpaper can't be loaded.
-                    Log.w(TAG, "Unable to load wallpaper!", exception);
-                    try {
-                        mWallpaperManager.clear();
-                    } catch (IOException ex) {
-                        // now we're really screwed.
-                        Log.w(TAG, "Unable reset to default wallpaper!", ex);
-                    }
-
-                    if (isCancelled()) {
-                        return null;
-                    }
-
-                    try {
-                        return mWallpaperManager.getBitmap(true /* hardware */);
-                    } catch (RuntimeException | OutOfMemoryError e) {
-                        Log.w(TAG, "Unable to load default wallpaper!", e);
-                    }
-                    return null;
-                }
-
-                @Override
-                protected void onPostExecute(Bitmap bitmap) {
-                    setBitmap(bitmap);
-
-                    if (mNeedsDrawAfterLoadingWallpaper) {
-                        drawFrame(true);
-                    }
-
-                    mLoader = null;
-                    mNeedsDrawAfterLoadingWallpaper = false;
-                    scheduleUnloadWallpaper();
-                }
-            }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
         }
 
-        private void unloadWallpaper() {
+        private void unloadBitmapIfNotUsedSynchronized() {
-            if (mLoader != null) {
+            synchronized (mLock) {
-                mLoader.cancel(false);
+                mBitmapUsages -= 1;
-                mLoader = null;
+                if (mBitmapUsages <= 0) {
+                    mBitmapUsages = 0;
+                    unloadBitmapInternal();
+                }
             }
+        }
 
+        private void unloadBitmap() {
+            mBackgroundExecutor.execute(this::unloadBitmapSynchronized);
+        }
+
+        private void unloadBitmapSynchronized() {
+            synchronized (mLock) {
+                mBitmapUsages = 0;
+                unloadBitmapInternal();
+            }
+        }
+
+        private void unloadBitmapInternal() {
+            Trace.beginSection("ImageWallpaper.CanvasEngine#unloadBitmap");
             if (mBitmap != null) {
                 mBitmap.recycle();
             }
@@ -750,12 +727,133 @@ public class ImageWallpaper extends WallpaperService {
             final Surface surface = getSurfaceHolder().getSurface();
             surface.hwuiDestroy();
             mWallpaperManager.forgetLoadedWallpaper();
+            Trace.endSection();
         }
 
-        private void scheduleUnloadWallpaper() {
+        private void loadWallpaperAndDrawFrameInternal() {
-            Handler handler = getMainThreadHandler();
+            Trace.beginSection("ImageWallpaper.CanvasEngine#loadWallpaper");
-            handler.removeCallbacks(mUnloadWallpaperCallback);
+            boolean loadSuccess = false;
-            handler.postDelayed(mUnloadWallpaperCallback, DELAY_FORGET_WALLPAPER);
+            Bitmap bitmap;
+            try {
+                bitmap = mWallpaperManager.getBitmap(false);
+                if (bitmap != null
+                        && bitmap.getByteCount() > RecordingCanvas.MAX_BITMAP_SIZE) {
+                    throw new RuntimeException("Wallpaper is too large to draw!");
+                }
+            } catch (RuntimeException | OutOfMemoryError exception) {
+
+                // Note that if we do fail at this, and the default wallpaper can't
+                // be loaded, we will go into a cycle. Don't do a build where the
+                // default wallpaper can't be loaded.
+                Log.w(TAG, "Unable to load wallpaper!", exception);
+                try {
+                    mWallpaperManager.clear(WallpaperManager.FLAG_SYSTEM);
+                } catch (IOException ex) {
+                    // now we're really screwed.
+                    Log.w(TAG, "Unable reset to default wallpaper!", ex);
+                }
+
+                try {
+                    bitmap = mWallpaperManager.getBitmap(false);
+                } catch (RuntimeException | OutOfMemoryError e) {
+                    Log.w(TAG, "Unable to load default wallpaper!", e);
+                    bitmap = null;
+                }
+            }
+
+            if (bitmap == null) {
+                Log.w(TAG, "Could not load bitmap");
+            } else if (bitmap.isRecycled()) {
+                Log.e(TAG, "Attempt to load a recycled bitmap");
+            } else if (mBitmap == bitmap) {
+                Log.e(TAG, "Loaded a bitmap that was already loaded");
+            } else if (bitmap.getWidth() < 1 || bitmap.getHeight() < 1) {
+                Log.e(TAG, "Attempt to load an invalid wallpaper of length "
+                        + bitmap.getWidth() + "x" + bitmap.getHeight());
+            } else {
+                // at this point, loading is done correctly.
+                loadSuccess = true;
+                // recycle the previously loaded bitmap
+                if (mBitmap != null) {
+                    mBitmap.recycle();
+                }
+                mBitmap = bitmap;
+
+                // +2 usages for the color extraction and the delayed unload.
+                mBitmapUsages += 2;
+                recomputeColorExtractorMiniBitmap();
+                drawFrameInternal();
+
+                /*
+                 * after loading, the bitmap will be unloaded after all these conditions:
+                 *   - the frame is redrawn
+                 *   - the mini bitmap from color extractor is recomputed
+                 *   - the DELAY_UNLOAD_BITMAP has passed
+                 */
+                mBackgroundExecutor.executeDelayed(
+                        this::unloadBitmapIfNotUsedSynchronized, DELAY_UNLOAD_BITMAP);
+            }
+            // even if the bitmap cannot be loaded, call reportEngineShown
+            if (!loadSuccess) reportEngineShown(false);
+            Trace.endSection();
+        }
+
+        private void onColorsProcessed(List<RectF> regions, List<WallpaperColors> colors) {
+            try {
+                notifyLocalColorsChanged(regions, colors);
+            } catch (RuntimeException e) {
+                Log.e(TAG, e.getMessage(), e);
+            }
+        }
+
+        @VisibleForTesting
+        void recomputeColorExtractorMiniBitmap() {
+            mWallpaperColorExtractor.onBitmapChanged(mBitmap);
+        }
+
+        @VisibleForTesting
+        void onMiniBitmapUpdated() {
+            unloadBitmapIfNotUsed();
+        }
+
+        @Override
+        public boolean supportsLocalColorExtraction() {
+            return true;
+        }
+
+        @Override
+        public void addLocalColorsAreas(@NonNull List<RectF> regions) {
+            // this call will activate the offset notifications
+            // if no colors were being processed before
+            mWallpaperColorExtractor.addLocalColorsAreas(regions);
+        }
+
+        @Override
+        public void removeLocalColorsAreas(@NonNull List<RectF> regions) {
+            // this call will deactivate the offset notifications
+            // if we are no longer processing colors
+            mWallpaperColorExtractor.removeLocalColorAreas(regions);
+        }
+
+        @Override
+        public void onOffsetsChanged(float xOffset, float yOffset,
+                float xOffsetStep, float yOffsetStep,
+                int xPixelOffset, int yPixelOffset) {
+            /*
+             * TODO check this formula. mPages is always >= 4, even when launcher is single-paged
+             * this formula is also used in the GL engine
+             */
+            final int pages;
+            if (xOffsetStep > 0 && xOffsetStep <= 1) {
+                pages = Math.round(1 / xOffsetStep) + 1;
+            } else {
+                pages = 1;
+            }
+            if (pages != mPages || !mPagesComputed) {
+                mPages = pages;
+                mPagesComputed = true;
+                mWallpaperColorExtractor.onPageChanged(mPages);
+            }
         }
 
         @Override
@@ -764,13 +862,46 @@ public class ImageWallpaper extends WallpaperService {
         }
 
         @Override
-        public void onDisplayChanged(int displayId) {
+        public void onDisplayRemoved(int displayId) {
 
         }
 
         @Override
-        public void onDisplayRemoved(int displayId) {
+        public void onDisplayChanged(int displayId) {
+            // changes the display in the color extractor
+            // the new display dimensions will be used in the next color computation
+            if (displayId == getDisplayContext().getDisplayId()) {
+                getDisplaySizeAndUpdateColorExtractor();
+            }
+        }
 
+        private void getDisplaySizeAndUpdateColorExtractor() {
+            Rect window = getDisplayContext()
+                    .getSystemService(WindowManager.class)
+                    .getCurrentWindowMetrics()
+                    .getBounds();
+            mWallpaperColorExtractor.setDisplayDimensions(window.width(), window.height());
+        }
+
+
+        @Override
+        protected void dump(String prefix, FileDescriptor fd, PrintWriter out, String[] args) {
+            super.dump(prefix, fd, out, args);
+            out.print(prefix); out.print("Engine="); out.println(this);
+            out.print(prefix); out.print("valid surface=");
+            out.println(getSurfaceHolder() != null && getSurfaceHolder().getSurface() != null
+                    ? getSurfaceHolder().getSurface().isValid()
+                    : "null");
+
+            out.print(prefix); out.print("surface frame=");
+            out.println(getSurfaceHolder() != null ? getSurfaceHolder().getSurfaceFrame() : "null");
+
+            out.print(prefix); out.print("bitmap=");
+            out.println(mBitmap == null ? "null"
+                    : mBitmap.isRecycled() ? "recycled"
+                    : mBitmap.getWidth() + "x" + mBitmap.getHeight());
+
+            mWallpaperColorExtractor.dump(prefix, fd, out, args);
         }
     }
 }

packages/SystemUI/src/com/android/systemui/wallpapers/canvas/ImageCanvasWallpaperRenderer.java

@@ -1,145 +0,0 @@
-/*
- * Copyright (C) 2022 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.wallpapers.canvas;
-
-import android.graphics.Bitmap;
-import android.graphics.Canvas;
-import android.graphics.Rect;
-import android.util.Log;
-import android.view.SurfaceHolder;
-
-import com.android.internal.annotations.VisibleForTesting;
-
-/**
- * Helper to draw a wallpaper on a surface.
- * It handles the geometry regarding the dimensions of the display and the wallpaper,
- * and rescales the surface and the wallpaper accordingly.
- */
-public class ImageCanvasWallpaperRenderer {
-
-    private static final String TAG = ImageCanvasWallpaperRenderer.class.getSimpleName();
-    private static final boolean DEBUG = false;
-
-    private SurfaceHolder mSurfaceHolder;
-    //private Bitmap mBitmap = null;
-
-    @VisibleForTesting
-    static final int MIN_SURFACE_WIDTH = 128;
-    @VisibleForTesting
-    static final int MIN_SURFACE_HEIGHT = 128;
-
-    private boolean mSurfaceRedrawNeeded;
-
-    private int mLastSurfaceWidth = -1;
-    private int mLastSurfaceHeight = -1;
-
-    public ImageCanvasWallpaperRenderer(SurfaceHolder surfaceHolder) {
-        mSurfaceHolder = surfaceHolder;
-    }
-
-    /**
-     * Set the surface holder on which to draw.
-     * Should be called when the surface holder is created or changed
-     * @param surfaceHolder the surface on which to draw the wallpaper
-     */
-    public void setSurfaceHolder(SurfaceHolder surfaceHolder) {
-        mSurfaceHolder = surfaceHolder;
-    }
-
-    /**
-     * Check if a surface holder is loaded
-     * @return true if a valid surfaceHolder has been set.
-     */
-    public boolean isSurfaceHolderLoaded() {
-        return mSurfaceHolder != null;
-    }
-
-    /**
-     * Computes and set the surface dimensions, by using the play and the bitmap dimensions.
-     * The Bitmap must be loaded before any call to this function
-     */
-    private boolean updateSurfaceSize(Bitmap bitmap) {
-        int surfaceWidth = Math.max(MIN_SURFACE_WIDTH, bitmap.getWidth());
-        int surfaceHeight = Math.max(MIN_SURFACE_HEIGHT, bitmap.getHeight());
-        boolean surfaceChanged =
-                surfaceWidth != mLastSurfaceWidth || surfaceHeight != mLastSurfaceHeight;
-        if (surfaceChanged) {
-            /*
-             Used a fixed size surface, because we are special.  We can do
-             this because we know the current design of window animations doesn't
-             cause this to break.
-            */
-            mSurfaceHolder.setFixedSize(surfaceWidth, surfaceHeight);
-            mLastSurfaceWidth = surfaceWidth;
-            mLastSurfaceHeight = surfaceHeight;
-        }
-        return surfaceChanged;
-    }
-
-    /**
-     * Draw a the wallpaper on the surface.
-     * The bitmap and the surface must be loaded before calling
-     * this function.
-     * @param forceRedraw redraw the wallpaper even if no changes are detected
-     */
-    public void drawFrame(Bitmap bitmap, boolean forceRedraw) {
-
-        if (bitmap == null || bitmap.isRecycled()) {
-            Log.e(TAG, "Attempt to draw frame before background is loaded:");
-            return;
-        }
-
-        if (bitmap.getWidth() < 1 || bitmap.getHeight() < 1) {
-            Log.e(TAG, "Attempt to set an invalid wallpaper of length "
-                    + bitmap.getWidth() + "x" + bitmap.getHeight());
-            return;
-        }
-
-        mSurfaceRedrawNeeded |= forceRedraw;
-        boolean surfaceChanged = updateSurfaceSize(bitmap);
-
-        boolean redrawNeeded = surfaceChanged || mSurfaceRedrawNeeded;
-        mSurfaceRedrawNeeded = false;
-
-        if (!redrawNeeded) {
-            if (DEBUG) {
-                Log.d(TAG, "Suppressed drawFrame since redraw is not needed ");
-            }
-            return;
-        }
-
-        if (DEBUG) {
-            Log.d(TAG, "Redrawing wallpaper");
-        }
-        drawWallpaperWithCanvas(bitmap);
-    }
-
-    @VisibleForTesting
-    void drawWallpaperWithCanvas(Bitmap bitmap) {
-        Canvas c = mSurfaceHolder.lockHardwareCanvas();
-        if (c != null) {
-            Rect dest = mSurfaceHolder.getSurfaceFrame();
-            Log.i(TAG, "Redrawing in rect: " + dest + " with surface size: "
-                    + mLastSurfaceWidth + "x" + mLastSurfaceHeight);
-            try {
-                c.drawBitmap(bitmap, null, dest, null);
-            } finally {
-                mSurfaceHolder.unlockCanvasAndPost(c);
-            }
-        }
-    }
-}

packages/SystemUI/src/com/android/systemui/wallpapers/canvas/WallpaperColorExtractor.java

@@ -0,0 +1,400 @@
+/*
+ * Copyright (C) 2022 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.wallpapers.canvas;
+
+import android.app.WallpaperColors;
+import android.graphics.Bitmap;
+import android.graphics.Rect;
+import android.graphics.RectF;
+import android.os.Trace;
+import android.util.ArraySet;
+import android.util.Log;
+import android.util.MathUtils;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.VisibleForTesting;
+
+import com.android.systemui.dagger.qualifiers.Background;
+import com.android.systemui.util.Assert;
+import com.android.systemui.wallpapers.ImageWallpaper;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.Executor;
+
+/**
+ * This class is used by the {@link ImageWallpaper} to extract colors from areas of a wallpaper.
+ * It uses a background executor, and uses callbacks to inform that the work is done.
+ * It uses  a downscaled version of the wallpaper to extract the colors.
+ */
+public class WallpaperColorExtractor {
+
+    private Bitmap mMiniBitmap;
+
+    @VisibleForTesting
+    static final int SMALL_SIDE = 128;
+
+    private static final String TAG = WallpaperColorExtractor.class.getSimpleName();
+    private static final @NonNull RectF LOCAL_COLOR_BOUNDS =
+            new RectF(0, 0, 1, 1);
+
+    private int mDisplayWidth = -1;
+    private int mDisplayHeight = -1;
+    private int mPages = -1;
+    private int mBitmapWidth = -1;
+    private int mBitmapHeight = -1;
+
+    private final Object mLock = new Object();
+
+    private final List<RectF> mPendingRegions = new ArrayList<>();
+    private final Set<RectF> mProcessedRegions = new ArraySet<>();
+
+    @Background
+    private final Executor mBackgroundExecutor;
+
+    private final WallpaperColorExtractorCallback mWallpaperColorExtractorCallback;
+
+    /**
+     * Interface to handle the callbacks after the different steps of the color extraction
+     */
+    public interface WallpaperColorExtractorCallback {
+        /**
+         * Callback after the colors of new regions have been extracted
+         * @param regions the list of new regions that have been processed
+         * @param colors the resulting colors for these regions, in the same order as the regions
+         */
+        void onColorsProcessed(List<RectF> regions, List<WallpaperColors> colors);
+
+        /**
+         * Callback after the mini bitmap is computed, to indicate that the wallpaper bitmap is
+         * no longer used by the color extractor and can be safely recycled
+         */
+        void onMiniBitmapUpdated();
+
+        /**
+         * Callback to inform that the extractor has started processing colors
+         */
+        void onActivated();
+
+        /**
+         * Callback to inform that no more colors are being processed
+         */
+        void onDeactivated();
+    }
+
+    /**
+     * Creates a new color extractor.
+     * @param backgroundExecutor the executor on which the color extraction will be performed
+     * @param wallpaperColorExtractorCallback an interface to handle the callbacks from
+     *                                        the color extractor.
+     */
+    public WallpaperColorExtractor(@Background Executor backgroundExecutor,
+            WallpaperColorExtractorCallback wallpaperColorExtractorCallback) {
+        mBackgroundExecutor = backgroundExecutor;
+        mWallpaperColorExtractorCallback = wallpaperColorExtractorCallback;
+    }
+
+    /**
+     * Used by the outside to inform that the display size has changed.
+     * The new display size will be used in the next computations, but the current colors are
+     * not recomputed.
+     */
+    public void setDisplayDimensions(int displayWidth, int displayHeight) {
+        mBackgroundExecutor.execute(() ->
+                setDisplayDimensionsSynchronized(displayWidth, displayHeight));
+    }
+
+    private void setDisplayDimensionsSynchronized(int displayWidth, int displayHeight) {
+        synchronized (mLock) {
+            if (displayWidth == mDisplayWidth && displayHeight == mDisplayHeight) return;
+            mDisplayWidth = displayWidth;
+            mDisplayHeight = displayHeight;
+            processColorsInternal();
+        }
+    }
+
+    /**
+     * @return whether color extraction is currently in use
+     */
+    private boolean isActive() {
+        return mPendingRegions.size() + mProcessedRegions.size() > 0;
+    }
+
+    /**
+     * Should be called when the wallpaper is changed.
+     * This will recompute the mini bitmap
+     * and restart the extraction of all areas
+     * @param bitmap the new wallpaper
+     */
+    public void onBitmapChanged(@NonNull Bitmap bitmap) {
+        mBackgroundExecutor.execute(() -> onBitmapChangedSynchronized(bitmap));
+    }
+
+    private void onBitmapChangedSynchronized(@NonNull Bitmap bitmap) {
+        synchronized (mLock) {
+            if (bitmap.getWidth() <= 0 || bitmap.getHeight() <= 0) {
+                Log.e(TAG, "Attempt to extract colors from an invalid bitmap");
+                return;
+            }
+            mBitmapWidth = bitmap.getWidth();
+            mBitmapHeight = bitmap.getHeight();
+            mMiniBitmap = createMiniBitmap(bitmap);
+            mWallpaperColorExtractorCallback.onMiniBitmapUpdated();
+            recomputeColors();
+        }
+    }
+
+    /**
+     * Should be called when the number of pages is changed
+     * This will restart the extraction of all areas
+     * @param pages the total number of pages of the launcher
+     */
+    public void onPageChanged(int pages) {
+        mBackgroundExecutor.execute(() -> onPageChangedSynchronized(pages));
+    }
+
+    private void onPageChangedSynchronized(int pages) {
+        synchronized (mLock) {
+            if (mPages == pages) return;
+            mPages = pages;
+            if (mMiniBitmap != null && !mMiniBitmap.isRecycled()) {
+                recomputeColors();
+            }
+        }
+    }
+
+    // helper to recompute colors, to be called in synchronized methods
+    private void recomputeColors() {
+        mPendingRegions.addAll(mProcessedRegions);
+        mProcessedRegions.clear();
+        processColorsInternal();
+    }
+
+    /**
+     * Add new regions to extract
+     * This will trigger the color extraction and call the callback only for these new regions
+     * @param regions The areas of interest in our wallpaper (in screen pixel coordinates)
+     */
+    public void addLocalColorsAreas(@NonNull List<RectF> regions) {
+        if (regions.size() > 0) {
+            mBackgroundExecutor.execute(() -> addLocalColorsAreasSynchronized(regions));
+        } else {
+            Log.w(TAG, "Attempt to add colors with an empty list");
+        }
+    }
+
+    private void addLocalColorsAreasSynchronized(@NonNull List<RectF> regions) {
+        synchronized (mLock) {
+            boolean wasActive = isActive();
+            mPendingRegions.addAll(regions);
+            if (!wasActive && isActive()) {
+                mWallpaperColorExtractorCallback.onActivated();
+            }
+            processColorsInternal();
+        }
+    }
+
+    /**
+     * Remove regions to extract. If a color extraction is ongoing does not stop it.
+     * But if there are subsequent changes that restart the extraction, the removed regions
+     * will not be recomputed.
+     * @param regions The areas of interest in our wallpaper (in screen pixel coordinates)
+     */
+    public void removeLocalColorAreas(@NonNull List<RectF> regions) {
+        mBackgroundExecutor.execute(() -> removeLocalColorAreasSynchronized(regions));
+    }
+
+    private void removeLocalColorAreasSynchronized(@NonNull List<RectF> regions) {
+        synchronized (mLock) {
+            boolean wasActive = isActive();
+            mPendingRegions.removeAll(regions);
+            regions.forEach(mProcessedRegions::remove);
+            if (wasActive && !isActive()) {
+                mWallpaperColorExtractorCallback.onDeactivated();
+            }
+        }
+    }
+
+    /**
+     * Clean up the memory (in particular, the mini bitmap) used by this class.
+     */
+    public void cleanUp() {
+        mBackgroundExecutor.execute(this::cleanUpSynchronized);
+    }
+
+    private void cleanUpSynchronized() {
+        synchronized (mLock) {
+            if (mMiniBitmap != null) {
+                mMiniBitmap.recycle();
+                mMiniBitmap = null;
+            }
+            mProcessedRegions.clear();
+            mPendingRegions.clear();
+        }
+    }
+
+    private Bitmap createMiniBitmap(@NonNull Bitmap bitmap) {
+        Trace.beginSection("WallpaperColorExtractor#createMiniBitmap");
+        // if both sides of the image are larger than SMALL_SIDE, downscale the bitmap.
+        int smallestSide = Math.min(bitmap.getWidth(), bitmap.getHeight());
+        float scale = Math.min(1.0f, (float) SMALL_SIDE / smallestSide);
+        Bitmap result = createMiniBitmap(bitmap,
+                (int) (scale * bitmap.getWidth()),
+                (int) (scale * bitmap.getHeight()));
+        Trace.endSection();
+        return result;
+    }
+
+    @VisibleForTesting
+    Bitmap createMiniBitmap(@NonNull Bitmap bitmap, int width, int height) {
+        return Bitmap.createScaledBitmap(bitmap, width, height, false);
+    }
+
+    private WallpaperColors getLocalWallpaperColors(@NonNull RectF area) {
+        RectF imageArea = pageToImgRect(area);
+        if (imageArea == null || !LOCAL_COLOR_BOUNDS.contains(imageArea)) {
+            return null;
+        }
+        Rect subImage = new Rect(
+                (int) Math.floor(imageArea.left * mMiniBitmap.getWidth()),
+                (int) Math.floor(imageArea.top * mMiniBitmap.getHeight()),
+                (int) Math.ceil(imageArea.right * mMiniBitmap.getWidth()),
+                (int) Math.ceil(imageArea.bottom * mMiniBitmap.getHeight()));
+        if (subImage.isEmpty()) {
+            // Do not notify client. treat it as too small to sample
+            return null;
+        }
+        return getLocalWallpaperColors(subImage);
+    }
+
+    @VisibleForTesting
+    WallpaperColors getLocalWallpaperColors(@NonNull Rect subImage) {
+        Assert.isNotMainThread();
+        Bitmap colorImg = Bitmap.createBitmap(mMiniBitmap,
+                subImage.left, subImage.top, subImage.width(), subImage.height());
+        return WallpaperColors.fromBitmap(colorImg);
+    }
+
+    /**
+     * Transform the logical coordinates into wallpaper coordinates.
+     *
+     * Logical coordinates are organised such that the various pages are non-overlapping. So,
+     * if there are n pages, the first page will have its X coordinate on the range [0-1/n].
+     *
+     * The real pages are overlapping. If the Wallpaper are a width Ww and the screen a width
+     * Ws, the relative width of a page Wr is Ws/Ww. This does not change if the number of
+     * pages increase.
+     * If there are n pages, the page k starts at the offset k * (1 - Wr) / (n - 1), as the
+     * last page is at position (1-Wr) and the others are regularly spread on the range [0-
+     * (1-Wr)].
+     */
+    private RectF pageToImgRect(RectF area) {
+        // Width of a page for the caller of this API.
+        float virtualPageWidth = 1f / (float) mPages;
+        float leftPosOnPage = (area.left % virtualPageWidth) / virtualPageWidth;
+        float rightPosOnPage = (area.right % virtualPageWidth) / virtualPageWidth;
+        int currentPage = (int) Math.floor(area.centerX() / virtualPageWidth);
+
+        if (mDisplayWidth <= 0 || mDisplayHeight <= 0) {
+            Log.e(TAG, "Trying to extract colors with invalid display dimensions");
+            return null;
+        }
+
+        RectF imgArea = new RectF();
+        imgArea.bottom = area.bottom;
+        imgArea.top = area.top;
+
+        float imageScale = Math.min(((float) mBitmapHeight) / mDisplayHeight, 1);
+        float mappedScreenWidth = mDisplayWidth * imageScale;
+        float pageWidth = Math.min(1.0f,
+                mBitmapWidth > 0 ? mappedScreenWidth / (float) mBitmapWidth : 1.f);
+        float pageOffset = (1 - pageWidth) / (float) (mPages - 1);
+
+        imgArea.left = MathUtils.constrain(
+                leftPosOnPage * pageWidth + currentPage * pageOffset, 0, 1);
+        imgArea.right = MathUtils.constrain(
+                rightPosOnPage * pageWidth + currentPage * pageOffset, 0, 1);
+        if (imgArea.left > imgArea.right) {
+            // take full page
+            imgArea.left = 0;
+            imgArea.right = 1;
+        }
+        return imgArea;
+    }
+
+    /**
+     * Extract the colors from the pending regions,
+     * then notify the callback with the resulting colors for these regions
+     * This method should only be called synchronously
+     */
+    private void processColorsInternal() {
+        /*
+         * if the miniBitmap is not yet loaded, that means the onBitmapChanged has not yet been
+         * called, and thus the wallpaper is not yet loaded. In that case, exit, the function
+         * will be called again when the bitmap is loaded and the miniBitmap is computed.
+         */
+        if (mMiniBitmap == null || mMiniBitmap.isRecycled())  return;
+
+        /*
+         * if the screen size or number of pages is not yet known, exit
+         * the function will be called again once the screen size and page are known
+         */
+        if (mDisplayWidth < 0 || mDisplayHeight < 0 || mPages < 0) return;
+
+        Trace.beginSection("WallpaperColorExtractor#processColorsInternal");
+        List<WallpaperColors> processedColors = new ArrayList<>();
+        for (int i = 0; i < mPendingRegions.size(); i++) {
+            RectF nextArea = mPendingRegions.get(i);
+            WallpaperColors colors = getLocalWallpaperColors(nextArea);
+
+            mProcessedRegions.add(nextArea);
+            processedColors.add(colors);
+        }
+        List<RectF> processedRegions = new ArrayList<>(mPendingRegions);
+        mPendingRegions.clear();
+        Trace.endSection();
+
+        mWallpaperColorExtractorCallback.onColorsProcessed(processedRegions, processedColors);
+    }
+
+    /**
+     * Called to dump current state.
+     * @param prefix prefix.
+     * @param fd fd.
+     * @param out out.
+     * @param args args.
+     */
+    public void dump(String prefix, FileDescriptor fd, PrintWriter out, String[] args) {
+        out.print(prefix); out.print("display="); out.println(mDisplayWidth + "x" + mDisplayHeight);
+        out.print(prefix); out.print("mPages="); out.println(mPages);
+
+        out.print(prefix); out.print("bitmap dimensions=");
+        out.println(mBitmapWidth + "x" + mBitmapHeight);
+
+        out.print(prefix); out.print("bitmap=");
+        out.println(mMiniBitmap == null ? "null"
+                : mMiniBitmap.isRecycled() ? "recycled"
+                : mMiniBitmap.getWidth() + "x" + mMiniBitmap.getHeight());
+
+        out.print(prefix); out.print("PendingRegions size="); out.print(mPendingRegions.size());
+        out.print(prefix); out.print("ProcessedRegions size="); out.print(mProcessedRegions.size());
+    }
+}

packages/SystemUI/tests/src/com/android/systemui/wallpapers/ImageWallpaperTest.java

@@ -16,14 +16,23 @@
 
 package com.android.systemui.wallpapers;
 
+import static com.google.common.truth.Truth.assertThat;
 import static com.google.common.truth.Truth.assertWithMessage;
 
+import static org.hamcrest.Matchers.greaterThanOrEqualTo;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyBoolean;
+import static org.mockito.Mockito.clearInvocations;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
+import static org.mockito.hamcrest.MockitoHamcrest.intThat;
 
 import android.app.WallpaperManager;
 import android.content.Context;
@@ -31,17 +40,25 @@ import android.content.res.Configuration;
 import android.content.res.Resources;
 import android.graphics.Bitmap;
 import android.graphics.ColorSpace;
+import android.graphics.Rect;
+import android.hardware.display.DisplayManager;
 import android.hardware.display.DisplayManagerGlobal;
 import android.os.Handler;
-import android.test.suitebuilder.annotation.SmallTest;
 import android.testing.AndroidTestingRunner;
 import android.testing.TestableLooper;
 import android.view.Display;
 import android.view.DisplayInfo;
+import android.view.Surface;
 import android.view.SurfaceHolder;
+import android.view.WindowManager;
+import android.view.WindowMetrics;
+
+import androidx.test.filters.SmallTest;
 
 import com.android.systemui.SysuiTestCase;
 import com.android.systemui.flags.FeatureFlags;
+import com.android.systemui.util.concurrency.FakeExecutor;
+import com.android.systemui.util.time.FakeSystemClock;
 import com.android.systemui.wallpapers.gl.ImageWallpaperRenderer;
 
 import org.junit.Before;
@@ -56,7 +73,6 @@ import java.util.concurrent.CountDownLatch;
 @SmallTest
 @RunWith(AndroidTestingRunner.class)
 @TestableLooper.RunWithLooper
-@Ignore
 public class ImageWallpaperTest extends SysuiTestCase {
     private static final int LOW_BMP_WIDTH = 128;
     private static final int LOW_BMP_HEIGHT = 128;
@@ -65,45 +81,87 @@ public class ImageWallpaperTest extends SysuiTestCase {
     private static final int DISPLAY_WIDTH = 1920;
     private static final int DISPLAY_HEIGHT = 1080;
 
+    @Mock
+    private WindowManager mWindowManager;
+    @Mock
+    private WindowMetrics mWindowMetrics;
+    @Mock
+    private DisplayManager mDisplayManager;
+    @Mock
+    private WallpaperManager mWallpaperManager;
     @Mock
     private SurfaceHolder mSurfaceHolder;
     @Mock
+    private Surface mSurface;
+    @Mock
     private Context mMockContext;
+
     @Mock
     private Bitmap mWallpaperBitmap;
+    private int mBitmapWidth = 1;
+    private int mBitmapHeight = 1;
+
     @Mock
     private Handler mHandler;
     @Mock
     private FeatureFlags mFeatureFlags;
 
+    FakeSystemClock mFakeSystemClock = new FakeSystemClock();
+    FakeExecutor mFakeMainExecutor = new FakeExecutor(mFakeSystemClock);
+    FakeExecutor mFakeBackgroundExecutor = new FakeExecutor(mFakeSystemClock);
+
     private CountDownLatch mEventCountdown;
 
     @Before
     public void setUp() throws Exception {
         allowTestableLooperAsMainThread();
         MockitoAnnotations.initMocks(this);
-        mEventCountdown = new CountDownLatch(1);
+        //mEventCountdown = new CountDownLatch(1);
 
-        WallpaperManager wallpaperManager = mock(WallpaperManager.class);
+        // set up window manager
+        when(mWindowMetrics.getBounds()).thenReturn(
+                new Rect(0, 0, DISPLAY_WIDTH, DISPLAY_HEIGHT));
+        when(mWindowManager.getCurrentWindowMetrics()).thenReturn(mWindowMetrics);
+        when(mMockContext.getSystemService(WindowManager.class)).thenReturn(mWindowManager);
+
+        // set up display manager
+        doNothing().when(mDisplayManager).registerDisplayListener(any(), any());
+        when(mMockContext.getSystemService(DisplayManager.class)).thenReturn(mDisplayManager);
+
+        // set up bitmap
+        when(mWallpaperBitmap.getColorSpace()).thenReturn(ColorSpace.get(ColorSpace.Named.SRGB));
+        when(mWallpaperBitmap.getConfig()).thenReturn(Bitmap.Config.ARGB_8888);
+        when(mWallpaperBitmap.getWidth()).thenReturn(mBitmapWidth);
+        when(mWallpaperBitmap.getHeight()).thenReturn(mBitmapHeight);
+
+        // set up wallpaper manager
+        when(mWallpaperManager.peekBitmapDimensions()).thenReturn(
+                new Rect(0, 0, mBitmapWidth, mBitmapHeight));
+        when(mWallpaperManager.getBitmap(false)).thenReturn(mWallpaperBitmap);
+        when(mMockContext.getSystemService(WallpaperManager.class)).thenReturn(mWallpaperManager);
+
+        // set up surface
+        when(mSurfaceHolder.getSurface()).thenReturn(mSurface);
+        doNothing().when(mSurface).hwuiDestroy();
+
+        // TODO remove code below. Outdated, used in only in old GL tests (that are ignored)
         Resources resources = mock(Resources.class);
-
-        when(mMockContext.getSystemService(WallpaperManager.class)).thenReturn(wallpaperManager);
-        when(mMockContext.getResources()).thenReturn(resources);
         when(resources.getConfiguration()).thenReturn(mock(Configuration.class));
-
+        when(mMockContext.getResources()).thenReturn(resources);
         DisplayInfo displayInfo = new DisplayInfo();
         displayInfo.logicalWidth = DISPLAY_WIDTH;
         displayInfo.logicalHeight = DISPLAY_HEIGHT;
         when(mMockContext.getDisplay()).thenReturn(
                 new Display(mock(DisplayManagerGlobal.class), 0, displayInfo, (Resources) null));
+    }
 
-        when(wallpaperManager.getBitmap(false)).thenReturn(mWallpaperBitmap);
+    private void setBitmapDimensions(int bitmapWidth, int bitmapHeight) {
-        when(mWallpaperBitmap.getColorSpace()).thenReturn(ColorSpace.get(ColorSpace.Named.SRGB));
+        mBitmapWidth = bitmapWidth;
-        when(mWallpaperBitmap.getConfig()).thenReturn(Bitmap.Config.ARGB_8888);
+        mBitmapHeight = bitmapHeight;
     }
 
     private ImageWallpaper createImageWallpaper() {
-        return new ImageWallpaper(mFeatureFlags) {
+        return new ImageWallpaper(mFeatureFlags, mFakeBackgroundExecutor, mFakeMainExecutor) {
             @Override
             public Engine onCreateEngine() {
                 return new GLEngine(mHandler) {
@@ -130,6 +188,7 @@ public class ImageWallpaperTest extends SysuiTestCase {
     }
 
     @Test
+    @Ignore
     public void testBitmapWallpaper_normal() {
         // Will use a image wallpaper with dimensions DISPLAY_WIDTH x DISPLAY_WIDTH.
         // Then we expect the surface size will be also DISPLAY_WIDTH x DISPLAY_WIDTH.
@@ -140,6 +199,7 @@ public class ImageWallpaperTest extends SysuiTestCase {
     }
 
     @Test
+    @Ignore
     public void testBitmapWallpaper_low_resolution() {
         // Will use a image wallpaper with dimensions BMP_WIDTH x BMP_HEIGHT.
         // Then we expect the surface size will be also BMP_WIDTH x BMP_HEIGHT.
@@ -150,6 +210,7 @@ public class ImageWallpaperTest extends SysuiTestCase {
     }
 
     @Test
+    @Ignore
     public void testBitmapWallpaper_too_small() {
         // Will use a image wallpaper with dimensions INVALID_BMP_WIDTH x INVALID_BMP_HEIGHT.
         // Then we expect the surface size will be also MIN_SURFACE_WIDTH x MIN_SURFACE_HEIGHT.
@@ -166,8 +227,7 @@ public class ImageWallpaperTest extends SysuiTestCase {
 
         ImageWallpaper.GLEngine engineSpy = spy(wallpaperEngine);
 
-        when(mWallpaperBitmap.getWidth()).thenReturn(bmpWidth);
+        setBitmapDimensions(bmpWidth, bmpHeight);
-        when(mWallpaperBitmap.getHeight()).thenReturn(bmpHeight);
 
         ImageWallpaperRenderer renderer = new ImageWallpaperRenderer(mMockContext);
         doReturn(renderer).when(engineSpy).getRendererInstance();
@@ -177,4 +237,116 @@ public class ImageWallpaperTest extends SysuiTestCase {
         assertWithMessage("setFixedSizeAllowed should have been called.").that(
                 mEventCountdown.getCount()).isEqualTo(0);
     }
+
+
+    private ImageWallpaper createImageWallpaperCanvas() {
+        return new ImageWallpaper(mFeatureFlags, mFakeBackgroundExecutor, mFakeMainExecutor) {
+            @Override
+            public Engine onCreateEngine() {
+                return new CanvasEngine() {
+                    @Override
+                    public Context getDisplayContext() {
+                        return mMockContext;
+                    }
+
+                    @Override
+                    public SurfaceHolder getSurfaceHolder() {
+                        return mSurfaceHolder;
+                    }
+
+                    @Override
+                    public void setFixedSizeAllowed(boolean allowed) {
+                        super.setFixedSizeAllowed(allowed);
+                        assertWithMessage("mFixedSizeAllowed should be true").that(
+                                allowed).isTrue();
+                    }
+                };
+            }
+        };
+    }
+
+    private ImageWallpaper.CanvasEngine getSpyEngine() {
+        ImageWallpaper imageWallpaper = createImageWallpaperCanvas();
+        ImageWallpaper.CanvasEngine engine =
+                (ImageWallpaper.CanvasEngine) imageWallpaper.onCreateEngine();
+        ImageWallpaper.CanvasEngine spyEngine = spy(engine);
+        doNothing().when(spyEngine).drawFrameOnCanvas(any(Bitmap.class));
+        doNothing().when(spyEngine).reportEngineShown(anyBoolean());
+        doAnswer(invocation -> {
+            ((ImageWallpaper.CanvasEngine) invocation.getMock()).onMiniBitmapUpdated();
+            return null;
+        }).when(spyEngine).recomputeColorExtractorMiniBitmap();
+        return spyEngine;
+    }
+
+    @Test
+    public void testMinSurface() {
+
+        // test that the surface is always at least MIN_SURFACE_WIDTH x MIN_SURFACE_HEIGHT
+        testMinSurfaceHelper(8, 8);
+        testMinSurfaceHelper(100, 2000);
+        testMinSurfaceHelper(200, 1);
+        testMinSurfaceHelper(0, 1);
+        testMinSurfaceHelper(1, 0);
+        testMinSurfaceHelper(0, 0);
+    }
+
+    private void testMinSurfaceHelper(int bitmapWidth, int bitmapHeight) {
+
+        clearInvocations(mSurfaceHolder);
+        setBitmapDimensions(bitmapWidth, bitmapHeight);
+
+        ImageWallpaper imageWallpaper = createImageWallpaperCanvas();
+        ImageWallpaper.CanvasEngine engine =
+                (ImageWallpaper.CanvasEngine) imageWallpaper.onCreateEngine();
+        engine.onCreate(mSurfaceHolder);
+
+        verify(mSurfaceHolder, times(1)).setFixedSize(
+                intThat(greaterThanOrEqualTo(ImageWallpaper.CanvasEngine.MIN_SURFACE_WIDTH)),
+                intThat(greaterThanOrEqualTo(ImageWallpaper.CanvasEngine.MIN_SURFACE_HEIGHT)));
+    }
+
+    @Test
+    public void testZeroBitmap() {
+        // test that a frame is never drawn with a 0 bitmap
+        testZeroBitmapHelper(0, 1);
+        testZeroBitmapHelper(1, 0);
+        testZeroBitmapHelper(0, 0);
+    }
+
+    private void testZeroBitmapHelper(int bitmapWidth, int bitmapHeight) {
+
+        clearInvocations(mSurfaceHolder);
+        setBitmapDimensions(bitmapWidth, bitmapHeight);
+
+        ImageWallpaper imageWallpaper = createImageWallpaperCanvas();
+        ImageWallpaper.CanvasEngine engine =
+                (ImageWallpaper.CanvasEngine) imageWallpaper.onCreateEngine();
+        ImageWallpaper.CanvasEngine spyEngine = spy(engine);
+        spyEngine.onCreate(mSurfaceHolder);
+        spyEngine.onSurfaceRedrawNeeded(mSurfaceHolder);
+        verify(spyEngine, never()).drawFrameOnCanvas(any());
+    }
+
+    @Test
+    public void testLoadDrawAndUnloadBitmap() {
+        setBitmapDimensions(LOW_BMP_WIDTH, LOW_BMP_HEIGHT);
+
+        ImageWallpaper.CanvasEngine spyEngine = getSpyEngine();
+        spyEngine.onCreate(mSurfaceHolder);
+        spyEngine.onSurfaceRedrawNeeded(mSurfaceHolder);
+        assertThat(mFakeBackgroundExecutor.numPending()).isAtLeast(1);
+
+        int n = 0;
+        while (mFakeBackgroundExecutor.numPending() + mFakeMainExecutor.numPending() >= 1) {
+            n++;
+            assertThat(n).isAtMost(10);
+            mFakeBackgroundExecutor.runNextReady();
+            mFakeMainExecutor.runNextReady();
+            mFakeSystemClock.advanceTime(1000);
+        }
+
+        verify(spyEngine, times(1)).drawFrameOnCanvas(mWallpaperBitmap);
+        assertThat(spyEngine.isBitmapLoaded()).isFalse();
+    }
 }

packages/SystemUI/tests/src/com/android/systemui/wallpapers/canvas/ImageCanvasWallpaperRendererTest.java

@@ -1,133 +0,0 @@
-/*
- * Copyright (C) 2022 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.wallpapers.canvas;
-
-import static org.hamcrest.Matchers.greaterThanOrEqualTo;
-import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.ArgumentMatchers.anyInt;
-import static org.mockito.Mockito.clearInvocations;
-import static org.mockito.Mockito.never;
-import static org.mockito.Mockito.spy;
-import static org.mockito.Mockito.times;
-import static org.mockito.Mockito.verify;
-import static org.mockito.Mockito.when;
-import static org.mockito.hamcrest.MockitoHamcrest.intThat;
-
-import android.graphics.Bitmap;
-import android.test.suitebuilder.annotation.SmallTest;
-import android.testing.AndroidTestingRunner;
-import android.testing.TestableLooper;
-import android.view.DisplayInfo;
-import android.view.SurfaceHolder;
-
-import com.android.systemui.SysuiTestCase;
-
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.Mock;
-import org.mockito.MockitoAnnotations;
-
-@SmallTest
-@RunWith(AndroidTestingRunner.class)
-@TestableLooper.RunWithLooper
-public class ImageCanvasWallpaperRendererTest extends SysuiTestCase {
-
-    private static final int MOBILE_DISPLAY_WIDTH = 720;
-    private static final int MOBILE_DISPLAY_HEIGHT = 1600;
-
-    @Mock
-    private SurfaceHolder mMockSurfaceHolder;
-
-    @Mock
-    private DisplayInfo mMockDisplayInfo;
-
-    @Mock
-    private Bitmap mMockBitmap;
-
-    @Before
-    public void setUp() throws Exception {
-        allowTestableLooperAsMainThread();
-        MockitoAnnotations.initMocks(this);
-    }
-
-    private void setDimensions(
-            int bitmapWidth, int bitmapHeight,
-            int displayWidth, int displayHeight) {
-        when(mMockBitmap.getWidth()).thenReturn(bitmapWidth);
-        when(mMockBitmap.getHeight()).thenReturn(bitmapHeight);
-        mMockDisplayInfo.logicalWidth = displayWidth;
-        mMockDisplayInfo.logicalHeight = displayHeight;
-    }
-
-    private void testMinDimensions(
-            int bitmapWidth, int bitmapHeight) {
-
-        clearInvocations(mMockSurfaceHolder);
-        setDimensions(bitmapWidth, bitmapHeight,
-                ImageCanvasWallpaperRendererTest.MOBILE_DISPLAY_WIDTH,
-                ImageCanvasWallpaperRendererTest.MOBILE_DISPLAY_HEIGHT);
-
-        ImageCanvasWallpaperRenderer renderer =
-                new ImageCanvasWallpaperRenderer(mMockSurfaceHolder);
-        renderer.drawFrame(mMockBitmap, true);
-
-        verify(mMockSurfaceHolder, times(1)).setFixedSize(
-                intThat(greaterThanOrEqualTo(ImageCanvasWallpaperRenderer.MIN_SURFACE_WIDTH)),
-                intThat(greaterThanOrEqualTo(ImageCanvasWallpaperRenderer.MIN_SURFACE_HEIGHT)));
-    }
-
-    @Test
-    public void testMinSurface() {
-        // test that the surface is always at least MIN_SURFACE_WIDTH x MIN_SURFACE_HEIGHT
-        testMinDimensions(8, 8);
-
-        testMinDimensions(100, 2000);
-
-        testMinDimensions(200, 1);
-    }
-
-    private void testZeroDimensions(int bitmapWidth, int bitmapHeight) {
-
-        clearInvocations(mMockSurfaceHolder);
-        setDimensions(bitmapWidth, bitmapHeight,
-                ImageCanvasWallpaperRendererTest.MOBILE_DISPLAY_WIDTH,
-                ImageCanvasWallpaperRendererTest.MOBILE_DISPLAY_HEIGHT);
-
-        ImageCanvasWallpaperRenderer renderer =
-                new ImageCanvasWallpaperRenderer(mMockSurfaceHolder);
-        ImageCanvasWallpaperRenderer spyRenderer = spy(renderer);
-        spyRenderer.drawFrame(mMockBitmap, true);
-
-        verify(mMockSurfaceHolder, never()).setFixedSize(anyInt(), anyInt());
-        verify(spyRenderer, never()).drawWallpaperWithCanvas(any());
-    }
-
-    @Test
-    public void testZeroBitmap() {
-        // test that updateSurfaceSize is not called with a bitmap of width 0 or height 0
-        testZeroDimensions(
-                0, 1
-        );
-
-        testZeroDimensions(1, 0
-        );
-
-        testZeroDimensions(0, 0
-        );
-    }
-}

packages/SystemUI/tests/src/com/android/systemui/wallpapers/canvas/WallpaperColorExtractorTest.java

@@ -0,0 +1,350 @@
+/*
+ * Copyright (C) 2022 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.wallpapers.canvas;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.when;
+
+import android.app.WallpaperColors;
+import android.graphics.Bitmap;
+import android.graphics.Color;
+import android.graphics.Rect;
+import android.graphics.RectF;
+import android.testing.AndroidTestingRunner;
+import android.testing.TestableLooper;
+
+import androidx.test.filters.SmallTest;
+
+import com.android.systemui.SysuiTestCase;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.Executor;
+
+@SmallTest
+@RunWith(AndroidTestingRunner.class)
+@TestableLooper.RunWithLooper
+public class WallpaperColorExtractorTest extends SysuiTestCase {
+    private static final int LOW_BMP_WIDTH = 128;
+    private static final int LOW_BMP_HEIGHT = 128;
+    private static final int HIGH_BMP_WIDTH = 3000;
+    private static final int HIGH_BMP_HEIGHT = 4000;
+    private static final int VERY_LOW_BMP_WIDTH = 1;
+    private static final int VERY_LOW_BMP_HEIGHT = 1;
+    private static final int DISPLAY_WIDTH = 1920;
+    private static final int DISPLAY_HEIGHT = 1080;
+
+    private static final int PAGES_LOW = 4;
+    private static final int PAGES_HIGH = 7;
+
+    private static final int MIN_AREAS = 4;
+    private static final int MAX_AREAS = 10;
+
+    private int mMiniBitmapWidth;
+    private int mMiniBitmapHeight;
+
+    @Mock
+    private Executor mBackgroundExecutor;
+
+    private int mColorsProcessed;
+    private int mMiniBitmapUpdatedCount;
+    private int mActivatedCount;
+    private int mDeactivatedCount;
+
+    @Before
+    public void setUp() throws Exception {
+        allowTestableLooperAsMainThread();
+        MockitoAnnotations.initMocks(this);
+        doAnswer(invocation ->  {
+            ((Runnable) invocation.getArgument(0)).run();
+            return null;
+        }).when(mBackgroundExecutor).execute(any(Runnable.class));
+    }
+
+    private void resetCounters() {
+        mColorsProcessed = 0;
+        mMiniBitmapUpdatedCount = 0;
+        mActivatedCount = 0;
+        mDeactivatedCount = 0;
+    }
+
+    private Bitmap getMockBitmap(int width, int height) {
+        Bitmap bitmap = mock(Bitmap.class);
+        when(bitmap.getWidth()).thenReturn(width);
+        when(bitmap.getHeight()).thenReturn(height);
+        return bitmap;
+    }
+
+    private WallpaperColorExtractor getSpyWallpaperColorExtractor() {
+
+        WallpaperColorExtractor wallpaperColorExtractor = new WallpaperColorExtractor(
+                mBackgroundExecutor,
+                new WallpaperColorExtractor.WallpaperColorExtractorCallback() {
+                    @Override
+                    public void onColorsProcessed(List<RectF> regions,
+                            List<WallpaperColors> colors) {
+                        assertThat(regions.size()).isEqualTo(colors.size());
+                        mColorsProcessed += regions.size();
+                    }
+
+                    @Override
+                    public void onMiniBitmapUpdated() {
+                        mMiniBitmapUpdatedCount++;
+                    }
+
+                    @Override
+                    public void onActivated() {
+                        mActivatedCount++;
+                    }
+
+                    @Override
+                    public void onDeactivated() {
+                        mDeactivatedCount++;
+                    }
+                });
+        WallpaperColorExtractor spyWallpaperColorExtractor = spy(wallpaperColorExtractor);
+
+        doAnswer(invocation -> {
+            mMiniBitmapWidth = invocation.getArgument(1);
+            mMiniBitmapHeight = invocation.getArgument(2);
+            return getMockBitmap(mMiniBitmapWidth, mMiniBitmapHeight);
+        }).when(spyWallpaperColorExtractor).createMiniBitmap(any(Bitmap.class), anyInt(), anyInt());
+
+
+        doAnswer(invocation -> getMockBitmap(
+                        invocation.getArgument(1),
+                        invocation.getArgument(2)))
+                .when(spyWallpaperColorExtractor)
+                .createMiniBitmap(any(Bitmap.class), anyInt(), anyInt());
+
+        doReturn(new WallpaperColors(Color.valueOf(0), Color.valueOf(0), Color.valueOf(0)))
+                .when(spyWallpaperColorExtractor).getLocalWallpaperColors(any(Rect.class));
+
+        return spyWallpaperColorExtractor;
+    }
+
+    private RectF randomArea() {
+        float width = (float) Math.random();
+        float startX = (float) (Math.random() * (1 - width));
+        float height = (float) Math.random();
+        float startY = (float) (Math.random() * (1 - height));
+        return new RectF(startX, startY, startX + width, startY + height);
+    }
+
+    private List<RectF> listOfRandomAreas(int min, int max) {
+        int nAreas = randomBetween(min, max);
+        List<RectF> result = new ArrayList<>();
+        for (int i = 0; i < nAreas; i++) {
+            result.add(randomArea());
+        }
+        return result;
+    }
+
+    private int randomBetween(int minIncluded, int maxIncluded) {
+        return (int) (Math.random() * ((maxIncluded - minIncluded) + 1)) + minIncluded;
+    }
+
+    /**
+     * Test that for bitmaps of random dimensions, the mini bitmap is always created
+     * with either a width <= SMALL_SIDE or a height <= SMALL_SIDE
+     */
+    @Test
+    public void testMiniBitmapCreation() {
+        WallpaperColorExtractor spyWallpaperColorExtractor = getSpyWallpaperColorExtractor();
+        int nSimulations = 10;
+        for (int i = 0; i < nSimulations; i++) {
+            resetCounters();
+            int width = randomBetween(LOW_BMP_WIDTH, HIGH_BMP_WIDTH);
+            int height = randomBetween(LOW_BMP_HEIGHT, HIGH_BMP_HEIGHT);
+            Bitmap bitmap = getMockBitmap(width, height);
+            spyWallpaperColorExtractor.onBitmapChanged(bitmap);
+
+            assertThat(mMiniBitmapUpdatedCount).isEqualTo(1);
+            assertThat(Math.min(mMiniBitmapWidth, mMiniBitmapHeight))
+                    .isAtMost(WallpaperColorExtractor.SMALL_SIDE);
+        }
+    }
+
+    /**
+     * Test that for bitmaps with both width and height <= SMALL_SIDE,
+     * the mini bitmap is always created with both width and height <= SMALL_SIDE
+     */
+    @Test
+    public void testSmallMiniBitmapCreation() {
+        WallpaperColorExtractor spyWallpaperColorExtractor = getSpyWallpaperColorExtractor();
+        int nSimulations = 10;
+        for (int i = 0; i < nSimulations; i++) {
+            resetCounters();
+            int width = randomBetween(VERY_LOW_BMP_WIDTH, LOW_BMP_WIDTH);
+            int height = randomBetween(VERY_LOW_BMP_HEIGHT, LOW_BMP_HEIGHT);
+            Bitmap bitmap = getMockBitmap(width, height);
+            spyWallpaperColorExtractor.onBitmapChanged(bitmap);
+
+            assertThat(mMiniBitmapUpdatedCount).isEqualTo(1);
+            assertThat(Math.max(mMiniBitmapWidth, mMiniBitmapHeight))
+                    .isAtMost(WallpaperColorExtractor.SMALL_SIDE);
+        }
+    }
+
+    /**
+     * Test that for a new color extractor with information
+     * (number of pages, display dimensions, wallpaper bitmap) given in random order,
+     * the colors are processed and all the callbacks are properly executed.
+     */
+    @Test
+    public void testNewColorExtraction() {
+        Bitmap bitmap = getMockBitmap(HIGH_BMP_WIDTH, HIGH_BMP_HEIGHT);
+
+        int nSimulations = 10;
+        for (int i = 0; i < nSimulations; i++) {
+            resetCounters();
+            WallpaperColorExtractor spyWallpaperColorExtractor = getSpyWallpaperColorExtractor();
+            List<RectF> regions = listOfRandomAreas(MIN_AREAS, MAX_AREAS);
+            int nPages = randomBetween(PAGES_LOW, PAGES_HIGH);
+            List<Runnable> tasks = Arrays.asList(
+                    () -> spyWallpaperColorExtractor.onPageChanged(nPages),
+                    () -> spyWallpaperColorExtractor.onBitmapChanged(bitmap),
+                    () -> spyWallpaperColorExtractor.setDisplayDimensions(
+                            DISPLAY_WIDTH, DISPLAY_HEIGHT),
+                    () -> spyWallpaperColorExtractor.addLocalColorsAreas(
+                            regions));
+            Collections.shuffle(tasks);
+            tasks.forEach(Runnable::run);
+
+            assertThat(mActivatedCount).isEqualTo(1);
+            assertThat(mMiniBitmapUpdatedCount).isEqualTo(1);
+            assertThat(mColorsProcessed).isEqualTo(regions.size());
+
+            spyWallpaperColorExtractor.removeLocalColorAreas(regions);
+            assertThat(mDeactivatedCount).isEqualTo(1);
+        }
+    }
+
+    /**
+     * Test that the method removeLocalColorAreas behaves properly and does not call
+     * the onDeactivated callback unless all color areas are removed.
+     */
+    @Test
+    public void testRemoveColors() {
+        Bitmap bitmap = getMockBitmap(HIGH_BMP_WIDTH, HIGH_BMP_HEIGHT);
+        int nSimulations = 10;
+        for (int i = 0; i < nSimulations; i++) {
+            resetCounters();
+            WallpaperColorExtractor spyWallpaperColorExtractor = getSpyWallpaperColorExtractor();
+            List<RectF> regions1 = listOfRandomAreas(MIN_AREAS / 2, MAX_AREAS / 2);
+            List<RectF> regions2 = listOfRandomAreas(MIN_AREAS / 2, MAX_AREAS / 2);
+            List<RectF> regions = new ArrayList<>();
+            regions.addAll(regions1);
+            regions.addAll(regions2);
+            int nPages = randomBetween(PAGES_LOW, PAGES_HIGH);
+            List<Runnable> tasks = Arrays.asList(
+                    () -> spyWallpaperColorExtractor.onPageChanged(nPages),
+                    () -> spyWallpaperColorExtractor.onBitmapChanged(bitmap),
+                    () -> spyWallpaperColorExtractor.setDisplayDimensions(
+                            DISPLAY_WIDTH, DISPLAY_HEIGHT),
+                    () -> spyWallpaperColorExtractor.removeLocalColorAreas(regions1));
+
+            spyWallpaperColorExtractor.addLocalColorsAreas(regions);
+            assertThat(mActivatedCount).isEqualTo(1);
+            Collections.shuffle(tasks);
+            tasks.forEach(Runnable::run);
+
+            assertThat(mMiniBitmapUpdatedCount).isEqualTo(1);
+            assertThat(mDeactivatedCount).isEqualTo(0);
+            spyWallpaperColorExtractor.removeLocalColorAreas(regions2);
+            assertThat(mDeactivatedCount).isEqualTo(1);
+        }
+    }
+
+    /**
+     * Test that if we change some information (wallpaper bitmap, number of pages),
+     * the colors are correctly recomputed.
+     * Test that if we remove some color areas in the middle of the process,
+     * only the remaining areas are recomputed.
+     */
+    @Test
+    public void testRecomputeColorExtraction() {
+        Bitmap bitmap = getMockBitmap(HIGH_BMP_WIDTH, HIGH_BMP_HEIGHT);
+        WallpaperColorExtractor spyWallpaperColorExtractor = getSpyWallpaperColorExtractor();
+        List<RectF> regions1 = listOfRandomAreas(MIN_AREAS / 2, MAX_AREAS / 2);
+        List<RectF> regions2 = listOfRandomAreas(MIN_AREAS / 2, MAX_AREAS / 2);
+        List<RectF> regions = new ArrayList<>();
+        regions.addAll(regions1);
+        regions.addAll(regions2);
+        spyWallpaperColorExtractor.addLocalColorsAreas(regions);
+        assertThat(mActivatedCount).isEqualTo(1);
+        int nPages = PAGES_LOW;
+        spyWallpaperColorExtractor.onBitmapChanged(bitmap);
+        spyWallpaperColorExtractor.onPageChanged(nPages);
+        spyWallpaperColorExtractor.setDisplayDimensions(DISPLAY_WIDTH, DISPLAY_HEIGHT);
+
+        int nSimulations = 20;
+        for (int i = 0; i < nSimulations; i++) {
+            resetCounters();
+
+            // verify that if we remove some regions, they are not recomputed after other changes
+            if (i == nSimulations / 2) {
+                regions.removeAll(regions2);
+                spyWallpaperColorExtractor.removeLocalColorAreas(regions2);
+            }
+
+            if (Math.random() >= 0.5) {
+                int nPagesNew = randomBetween(PAGES_LOW, PAGES_HIGH);
+                if (nPagesNew == nPages) continue;
+                nPages = nPagesNew;
+                spyWallpaperColorExtractor.onPageChanged(nPagesNew);
+            } else {
+                Bitmap newBitmap = getMockBitmap(HIGH_BMP_WIDTH, HIGH_BMP_HEIGHT);
+                spyWallpaperColorExtractor.onBitmapChanged(newBitmap);
+                assertThat(mMiniBitmapUpdatedCount).isEqualTo(1);
+            }
+            assertThat(mColorsProcessed).isEqualTo(regions.size());
+        }
+        spyWallpaperColorExtractor.removeLocalColorAreas(regions);
+        assertThat(mDeactivatedCount).isEqualTo(1);
+    }
+
+    @Test
+    public void testCleanUp() {
+        resetCounters();
+        Bitmap bitmap = getMockBitmap(HIGH_BMP_WIDTH, HIGH_BMP_HEIGHT);
+        doNothing().when(bitmap).recycle();
+        WallpaperColorExtractor spyWallpaperColorExtractor = getSpyWallpaperColorExtractor();
+        spyWallpaperColorExtractor.onPageChanged(PAGES_LOW);
+        spyWallpaperColorExtractor.onBitmapChanged(bitmap);
+        assertThat(mMiniBitmapUpdatedCount).isEqualTo(1);
+        spyWallpaperColorExtractor.cleanUp();
+        spyWallpaperColorExtractor.addLocalColorsAreas(listOfRandomAreas(MIN_AREAS, MAX_AREAS));
+        assertThat(mColorsProcessed).isEqualTo(0);
+    }
+}