| /* |
| * Copyright (C) 2017 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 android.app; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.graphics.Bitmap; |
| import android.graphics.Canvas; |
| import android.graphics.Color; |
| import android.graphics.drawable.Drawable; |
| import android.os.Parcel; |
| import android.os.Parcelable; |
| import android.util.Size; |
| |
| import com.android.internal.graphics.ColorUtils; |
| import com.android.internal.graphics.palette.Palette; |
| import com.android.internal.graphics.palette.VariationalKMeansQuantizer; |
| |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| |
| /** |
| * Provides information about the colors of a wallpaper. |
| * <p> |
| * Exposes the 3 most visually representative colors of a wallpaper. Can be either |
| * {@link WallpaperColors#getPrimaryColor()}, {@link WallpaperColors#getSecondaryColor()} |
| * or {@link WallpaperColors#getTertiaryColor()}. |
| */ |
| public final class WallpaperColors implements Parcelable { |
| |
| /** |
| * Specifies that dark text is preferred over the current wallpaper for best presentation. |
| * <p> |
| * eg. A launcher may set its text color to black if this flag is specified. |
| * @hide |
| */ |
| public static final int HINT_SUPPORTS_DARK_TEXT = 0x1; |
| |
| /** |
| * Specifies that dark theme is preferred over the current wallpaper for best presentation. |
| * <p> |
| * eg. A launcher may set its drawer color to black if this flag is specified. |
| * @hide |
| */ |
| public static final int HINT_SUPPORTS_DARK_THEME = 0x2; |
| |
| // Maximum size that a bitmap can have to keep our calculations sane |
| private static final int MAX_BITMAP_SIZE = 112; |
| |
| // Even though we have a maximum size, we'll mainly match bitmap sizes |
| // using the area instead. This way our comparisons are aspect ratio independent. |
| private static final int MAX_WALLPAPER_EXTRACTION_AREA = MAX_BITMAP_SIZE * MAX_BITMAP_SIZE; |
| |
| // When extracting the main colors, only consider colors |
| // present in at least MIN_COLOR_OCCURRENCE of the image |
| private static final float MIN_COLOR_OCCURRENCE = 0.05f; |
| |
| // Decides when dark theme is optimal for this wallpaper |
| private static final float DARK_THEME_MEAN_LUMINANCE = 0.25f; |
| // Minimum mean luminosity that an image needs to have to support dark text |
| private static final float BRIGHT_IMAGE_MEAN_LUMINANCE = 0.75f; |
| // We also check if the image has dark pixels in it, |
| // to avoid bright images with some dark spots. |
| private static final float DARK_PIXEL_LUMINANCE = 0.45f; |
| private static final float MAX_DARK_AREA = 0.05f; |
| |
| private final ArrayList<Color> mMainColors; |
| private int mColorHints; |
| |
| public WallpaperColors(Parcel parcel) { |
| mMainColors = new ArrayList<>(); |
| final int count = parcel.readInt(); |
| for (int i = 0; i < count; i++) { |
| final int colorInt = parcel.readInt(); |
| Color color = Color.valueOf(colorInt); |
| mMainColors.add(color); |
| } |
| mColorHints = parcel.readInt(); |
| } |
| |
| /** |
| * Constructs {@link WallpaperColors} from a drawable. |
| * <p> |
| * Main colors will be extracted from the drawable. |
| * |
| * @param drawable Source where to extract from. |
| */ |
| public static WallpaperColors fromDrawable(Drawable drawable) { |
| int width = drawable.getIntrinsicWidth(); |
| int height = drawable.getIntrinsicHeight(); |
| |
| // Some drawables do not have intrinsic dimensions |
| if (width <= 0 || height <= 0) { |
| width = MAX_BITMAP_SIZE; |
| height = MAX_BITMAP_SIZE; |
| } |
| |
| Size optimalSize = calculateOptimalSize(width, height); |
| Bitmap bitmap = Bitmap.createBitmap(optimalSize.getWidth(), optimalSize.getHeight(), |
| Bitmap.Config.ARGB_8888); |
| final Canvas bmpCanvas = new Canvas(bitmap); |
| drawable.setBounds(0, 0, bitmap.getWidth(), bitmap.getHeight()); |
| drawable.draw(bmpCanvas); |
| |
| final WallpaperColors colors = WallpaperColors.fromBitmap(bitmap); |
| bitmap.recycle(); |
| |
| return colors; |
| } |
| |
| /** |
| * Constructs {@link WallpaperColors} from a bitmap. |
| * <p> |
| * Main colors will be extracted from the bitmap. |
| * |
| * @param bitmap Source where to extract from. |
| */ |
| public static WallpaperColors fromBitmap(@NonNull Bitmap bitmap) { |
| if (bitmap == null) { |
| throw new IllegalArgumentException("Bitmap can't be null"); |
| } |
| |
| final int bitmapArea = bitmap.getWidth() * bitmap.getHeight(); |
| boolean shouldRecycle = false; |
| if (bitmapArea > MAX_WALLPAPER_EXTRACTION_AREA) { |
| shouldRecycle = true; |
| Size optimalSize = calculateOptimalSize(bitmap.getWidth(), bitmap.getHeight()); |
| bitmap = Bitmap.createScaledBitmap(bitmap, optimalSize.getWidth(), |
| optimalSize.getHeight(), true /* filter */); |
| } |
| |
| final Palette palette = Palette |
| .from(bitmap) |
| .setQuantizer(new VariationalKMeansQuantizer()) |
| .maximumColorCount(5) |
| .clearFilters() |
| .resizeBitmapArea(MAX_WALLPAPER_EXTRACTION_AREA) |
| .generate(); |
| |
| // Remove insignificant colors and sort swatches by population |
| final ArrayList<Palette.Swatch> swatches = new ArrayList<>(palette.getSwatches()); |
| final float minColorArea = bitmap.getWidth() * bitmap.getHeight() * MIN_COLOR_OCCURRENCE; |
| swatches.removeIf(s -> s.getPopulation() < minColorArea); |
| swatches.sort((a, b) -> b.getPopulation() - a.getPopulation()); |
| |
| final int swatchesSize = swatches.size(); |
| Color primary = null, secondary = null, tertiary = null; |
| |
| swatchLoop: |
| for (int i = 0; i < swatchesSize; i++) { |
| Color color = Color.valueOf(swatches.get(i).getRgb()); |
| switch (i) { |
| case 0: |
| primary = color; |
| break; |
| case 1: |
| secondary = color; |
| break; |
| case 2: |
| tertiary = color; |
| break; |
| default: |
| // out of bounds |
| break swatchLoop; |
| } |
| } |
| |
| int hints = calculateHints(bitmap); |
| |
| if (shouldRecycle) { |
| bitmap.recycle(); |
| } |
| |
| return new WallpaperColors(primary, secondary, tertiary, hints); |
| } |
| |
| /** |
| * Constructs a new object from three colors. |
| * |
| * @param primaryColor Primary color. |
| * @param secondaryColor Secondary color. |
| * @param tertiaryColor Tertiary color. |
| * @see WallpaperColors#fromBitmap(Bitmap) |
| * @see WallpaperColors#fromDrawable(Drawable) |
| */ |
| public WallpaperColors(@NonNull Color primaryColor, @Nullable Color secondaryColor, |
| @Nullable Color tertiaryColor) { |
| this(primaryColor, secondaryColor, tertiaryColor, 0); |
| } |
| |
| /** |
| * Constructs a new object from three colors, where hints can be specified. |
| * |
| * @param primaryColor Primary color. |
| * @param secondaryColor Secondary color. |
| * @param tertiaryColor Tertiary color. |
| * @param colorHints A combination of WallpaperColor hints. |
| * @see WallpaperColors#HINT_SUPPORTS_DARK_TEXT |
| * @see WallpaperColors#fromBitmap(Bitmap) |
| * @see WallpaperColors#fromDrawable(Drawable) |
| * @hide |
| */ |
| public WallpaperColors(@NonNull Color primaryColor, @Nullable Color secondaryColor, |
| @Nullable Color tertiaryColor, int colorHints) { |
| |
| if (primaryColor == null) { |
| throw new IllegalArgumentException("Primary color should never be null."); |
| } |
| |
| mMainColors = new ArrayList<>(3); |
| mMainColors.add(primaryColor); |
| if (secondaryColor != null) { |
| mMainColors.add(secondaryColor); |
| } |
| if (tertiaryColor != null) { |
| if (secondaryColor == null) { |
| throw new IllegalArgumentException("tertiaryColor can't be specified when " |
| + "secondaryColor is null"); |
| } |
| mMainColors.add(tertiaryColor); |
| } |
| |
| mColorHints = colorHints; |
| } |
| |
| public static final Creator<WallpaperColors> CREATOR = new Creator<WallpaperColors>() { |
| @Override |
| public WallpaperColors createFromParcel(Parcel in) { |
| return new WallpaperColors(in); |
| } |
| |
| @Override |
| public WallpaperColors[] newArray(int size) { |
| return new WallpaperColors[size]; |
| } |
| }; |
| |
| @Override |
| public int describeContents() { |
| return 0; |
| } |
| |
| @Override |
| public void writeToParcel(Parcel dest, int flags) { |
| List<Color> mainColors = getMainColors(); |
| int count = mainColors.size(); |
| dest.writeInt(count); |
| for (int i = 0; i < count; i++) { |
| Color color = mainColors.get(i); |
| dest.writeInt(color.toArgb()); |
| } |
| dest.writeInt(mColorHints); |
| } |
| |
| /** |
| * Gets the most visually representative color of the wallpaper. |
| * "Visually representative" means easily noticeable in the image, |
| * probably happening at high frequency. |
| * |
| * @return A color. |
| */ |
| public @NonNull Color getPrimaryColor() { |
| return mMainColors.get(0); |
| } |
| |
| /** |
| * Gets the second most preeminent color of the wallpaper. Can be null. |
| * |
| * @return A color, may be null. |
| */ |
| public @Nullable Color getSecondaryColor() { |
| return mMainColors.size() < 2 ? null : mMainColors.get(1); |
| } |
| |
| /** |
| * Gets the third most preeminent color of the wallpaper. Can be null. |
| * |
| * @return A color, may be null. |
| */ |
| public @Nullable Color getTertiaryColor() { |
| return mMainColors.size() < 3 ? null : mMainColors.get(2); |
| } |
| |
| /** |
| * List of most preeminent colors, sorted by importance. |
| * |
| * @return List of colors. |
| * @hide |
| */ |
| public @NonNull List<Color> getMainColors() { |
| return Collections.unmodifiableList(mMainColors); |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (o == null || getClass() != o.getClass()) { |
| return false; |
| } |
| |
| WallpaperColors other = (WallpaperColors) o; |
| return mMainColors.equals(other.mMainColors) |
| && mColorHints == other.mColorHints; |
| } |
| |
| @Override |
| public int hashCode() { |
| return 31 * mMainColors.hashCode() + mColorHints; |
| } |
| |
| /** |
| * Combination of WallpaperColor hints. |
| * |
| * @see WallpaperColors#HINT_SUPPORTS_DARK_TEXT |
| * @return True if dark text is supported. |
| * @hide |
| */ |
| public int getColorHints() { |
| return mColorHints; |
| } |
| |
| /** |
| * @param colorHints Combination of WallpaperColors hints. |
| * @see WallpaperColors#HINT_SUPPORTS_DARK_TEXT |
| * @hide |
| */ |
| public void setColorHints(int colorHints) { |
| mColorHints = colorHints; |
| } |
| |
| /** |
| * Checks if image is bright and clean enough to support light text. |
| * |
| * @param source What to read. |
| * @return Whether image supports dark text or not. |
| */ |
| private static int calculateHints(Bitmap source) { |
| if (source == null) { |
| return 0; |
| } |
| |
| int[] pixels = new int[source.getWidth() * source.getHeight()]; |
| double totalLuminance = 0; |
| final int maxDarkPixels = (int) (pixels.length * MAX_DARK_AREA); |
| int darkPixels = 0; |
| source.getPixels(pixels, 0 /* offset */, source.getWidth(), 0 /* x */, 0 /* y */, |
| source.getWidth(), source.getHeight()); |
| |
| // This bitmap was already resized to fit the maximum allowed area. |
| // Let's just loop through the pixels, no sweat! |
| float[] tmpHsl = new float[3]; |
| for (int i = 0; i < pixels.length; i++) { |
| ColorUtils.colorToHSL(pixels[i], tmpHsl); |
| final float luminance = tmpHsl[2]; |
| final int alpha = Color.alpha(pixels[i]); |
| // Make sure we don't have a dark pixel mass that will |
| // make text illegible. |
| if (luminance < DARK_PIXEL_LUMINANCE && alpha != 0) { |
| darkPixels++; |
| } |
| totalLuminance += luminance; |
| } |
| |
| int hints = 0; |
| double meanLuminance = totalLuminance / pixels.length; |
| if (meanLuminance > BRIGHT_IMAGE_MEAN_LUMINANCE && darkPixels < maxDarkPixels) { |
| hints |= HINT_SUPPORTS_DARK_TEXT; |
| } |
| if (meanLuminance < DARK_THEME_MEAN_LUMINANCE) { |
| hints |= HINT_SUPPORTS_DARK_THEME; |
| } |
| |
| return hints; |
| } |
| |
| private static Size calculateOptimalSize(int width, int height) { |
| // Calculate how big the bitmap needs to be. |
| // This avoids unnecessary processing and allocation inside Palette. |
| final int requestedArea = width * height; |
| double scale = 1; |
| if (requestedArea > MAX_WALLPAPER_EXTRACTION_AREA) { |
| scale = Math.sqrt(MAX_WALLPAPER_EXTRACTION_AREA / (double) requestedArea); |
| } |
| int newWidth = (int) (width * scale); |
| int newHeight = (int) (height * scale); |
| // Dealing with edge cases of the drawable being too wide or too tall. |
| // Width or height would end up being 0, in this case we'll set it to 1. |
| if (newWidth == 0) { |
| newWidth = 1; |
| } |
| if (newHeight == 0) { |
| newHeight = 1; |
| } |
| |
| return new Size(newWidth, newHeight); |
| } |
| } |