diff --git a/api/lineage_current.txt b/api/lineage_current.txt index bce4e37e..eb4dabfe 100644 --- a/api/lineage_current.txt +++ b/api/lineage_current.txt @@ -1622,7 +1622,7 @@ package lineageos.util { method public static int findPerceptuallyNearestColor(int, int[]); method public static int findPerceptuallyNearestSolidColor(int); method public static int generateAlertColorFromDrawable(android.graphics.drawable.Drawable); - method public static com.android.internal.util.cm.palette.Palette.Swatch getDominantSwatch(com.android.internal.util.cm.palette.Palette); + method public static lineageos.util.palette.Palette.Swatch getDominantSwatch(lineageos.util.palette.Palette); method public static float[] temperatureToRGB(int); } diff --git a/sdk/src/java/lineageos/util/palette/ColorCutQuantizer.java b/sdk/src/java/lineageos/util/palette/ColorCutQuantizer.java new file mode 100644 index 00000000..374669b3 --- /dev/null +++ b/sdk/src/java/lineageos/util/palette/ColorCutQuantizer.java @@ -0,0 +1,517 @@ +/* + * Copyright 2014 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 lineageos.util.palette; + +import android.graphics.Color; +import android.util.TimingLogger; + +import lineageos.util.palette.Palette.Swatch; + +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Collection; +import java.util.Comparator; +import java.util.List; +import java.util.PriorityQueue; + +/** + * An color quantizer based on the Median-cut algorithm, but optimized for picking out distinct + * colors rather than representation colors. + * + * The color space is represented as a 3-dimensional cube with each dimension being an RGB + * component. The cube is then repeatedly divided until we have reduced the color space to the + * requested number of colors. An average color is then generated from each cube. + * + * What makes this different to median-cut is that median-cut divided cubes so that all of the cubes + * have roughly the same population, where this quantizer divides boxes based on their color volume. + * This means that the color space is divided into distinct colors, rather than representative + * colors. + * + * @hide + */ +final class ColorCutQuantizer { + + private static final String LOG_TAG = "ColorCutQuantizer"; + private static final boolean LOG_TIMINGS = false; + + private static final int COMPONENT_RED = -3; + private static final int COMPONENT_GREEN = -2; + private static final int COMPONENT_BLUE = -1; + + private static final int QUANTIZE_WORD_WIDTH = 5; + private static final int QUANTIZE_WORD_MASK = (1 << QUANTIZE_WORD_WIDTH) - 1; + + final int[] mColors; + final int[] mHistogram; + final List mQuantizedColors; + final TimingLogger mTimingLogger; + final Palette.Filter[] mFilters; + + private final float[] mTempHsl = new float[3]; + + /** + * Constructor. + * + * @param pixels histogram representing an image's pixel data + * @param maxColors The maximum number of colors that should be in the result palette. + * @param filters Set of filters to use in the quantization stage + */ + ColorCutQuantizer(final int[] pixels, final int maxColors, final Palette.Filter[] filters) { + mTimingLogger = LOG_TIMINGS ? new TimingLogger(LOG_TAG, "Creation") : null; + mFilters = filters; + + final int[] hist = mHistogram = new int[1 << (QUANTIZE_WORD_WIDTH * 3)]; + for (int i = 0; i < pixels.length; i++) { + final int quantizedColor = quantizeFromRgb888(pixels[i]); + // Now update the pixel value to the quantized value + pixels[i] = quantizedColor; + // And update the histogram + hist[quantizedColor]++; + } + + if (LOG_TIMINGS) { + mTimingLogger.addSplit("Histogram created"); + } + + // Now let's count the number of distinct colors + int distinctColorCount = 0; + for (int color = 0; color < hist.length; color++) { + if (hist[color] > 0 && shouldIgnoreColor(color)) { + // If we should ignore the color, set the population to 0 + hist[color] = 0; + } + if (hist[color] > 0) { + // If the color has population, increase the distinct color count + distinctColorCount++; + } + } + + if (LOG_TIMINGS) { + mTimingLogger.addSplit("Filtered colors and distinct colors counted"); + } + + // Now lets go through create an array consisting of only distinct colors + final int[] colors = mColors = new int[distinctColorCount]; + int distinctColorIndex = 0; + for (int color = 0; color < hist.length; color++) { + if (hist[color] > 0) { + colors[distinctColorIndex++] = color; + } + } + + if (LOG_TIMINGS) { + mTimingLogger.addSplit("Distinct colors copied into array"); + } + + if (distinctColorCount <= maxColors) { + // The image has fewer colors than the maximum requested, so just return the colors + mQuantizedColors = new ArrayList<>(); + for (int color : colors) { + mQuantizedColors.add(new Swatch(approximateToRgb888(color), hist[color])); + } + + if (LOG_TIMINGS) { + mTimingLogger.addSplit("Too few colors present. Copied to Swatches"); + mTimingLogger.dumpToLog(); + } + } else { + // We need use quantization to reduce the number of colors + mQuantizedColors = quantizePixels(maxColors); + + if (LOG_TIMINGS) { + mTimingLogger.addSplit("Quantized colors computed"); + mTimingLogger.dumpToLog(); + } + } + } + + /** + * @return the list of quantized colors + */ + List getQuantizedColors() { + return mQuantizedColors; + } + + private List quantizePixels(int maxColors) { + // Create the priority queue which is sorted by volume descending. This means we always + // split the largest box in the queue + final PriorityQueue pq = new PriorityQueue<>(maxColors, VBOX_COMPARATOR_VOLUME); + + // To start, offer a box which contains all of the colors + pq.offer(new Vbox(0, mColors.length - 1)); + + // Now go through the boxes, splitting them until we have reached maxColors or there are no + // more boxes to split + splitBoxes(pq, maxColors); + + // Finally, return the average colors of the color boxes + return generateAverageColors(pq); + } + + /** + * Iterate through the {@link java.util.Queue}, popping + * {@link ColorCutQuantizer.Vbox} objects from the queue + * and splitting them. Once split, the new box and the remaining box are offered back to the + * queue. + * + * @param queue {@link java.util.PriorityQueue} to poll for boxes + * @param maxSize Maximum amount of boxes to split + */ + private void splitBoxes(final PriorityQueue queue, final int maxSize) { + while (queue.size() < maxSize) { + final Vbox vbox = queue.poll(); + + if (vbox != null && vbox.canSplit()) { + // First split the box, and offer the result + queue.offer(vbox.splitBox()); + + if (LOG_TIMINGS) { + mTimingLogger.addSplit("Box split"); + } + // Then offer the box back + queue.offer(vbox); + } else { + if (LOG_TIMINGS) { + mTimingLogger.addSplit("All boxes split"); + } + // If we get here then there are no more boxes to split, so return + return; + } + } + } + + private List generateAverageColors(Collection vboxes) { + ArrayList colors = new ArrayList<>(vboxes.size()); + for (Vbox vbox : vboxes) { + Swatch swatch = vbox.getAverageColor(); + if (!shouldIgnoreColor(swatch)) { + // As we're averaging a color box, we can still get colors which we do not want, so + // we check again here + colors.add(swatch); + } + } + return colors; + } + + /** + * Represents a tightly fitting box around a color space. + */ + private class Vbox { + // lower and upper index are inclusive + private int mLowerIndex; + private int mUpperIndex; + // Population of colors within this box + private int mPopulation; + + private int mMinRed, mMaxRed; + private int mMinGreen, mMaxGreen; + private int mMinBlue, mMaxBlue; + + Vbox(int lowerIndex, int upperIndex) { + mLowerIndex = lowerIndex; + mUpperIndex = upperIndex; + fitBox(); + } + + final int getVolume() { + return (mMaxRed - mMinRed + 1) * (mMaxGreen - mMinGreen + 1) * + (mMaxBlue - mMinBlue + 1); + } + + final boolean canSplit() { + return getColorCount() > 1; + } + + final int getColorCount() { + return 1 + mUpperIndex - mLowerIndex; + } + + /** + * Recomputes the boundaries of this box to tightly fit the colors within the box. + */ + final void fitBox() { + final int[] colors = mColors; + final int[] hist = mHistogram; + + // Reset the min and max to opposite values + int minRed, minGreen, minBlue; + minRed = minGreen = minBlue = Integer.MAX_VALUE; + int maxRed, maxGreen, maxBlue; + maxRed = maxGreen = maxBlue = Integer.MIN_VALUE; + int count = 0; + + for (int i = mLowerIndex; i <= mUpperIndex; i++) { + final int color = colors[i]; + count += hist[color]; + + final int r = quantizedRed(color); + final int g = quantizedGreen(color); + final int b = quantizedBlue(color); + if (r > maxRed) { + maxRed = r; + } + if (r < minRed) { + minRed = r; + } + if (g > maxGreen) { + maxGreen = g; + } + if (g < minGreen) { + minGreen = g; + } + if (b > maxBlue) { + maxBlue = b; + } + if (b < minBlue) { + minBlue = b; + } + } + + mMinRed = minRed; + mMaxRed = maxRed; + mMinGreen = minGreen; + mMaxGreen = maxGreen; + mMinBlue = minBlue; + mMaxBlue = maxBlue; + mPopulation = count; + } + + /** + * Split this color box at the mid-point along it's longest dimension + * + * @return the new ColorBox + */ + final Vbox splitBox() { + if (!canSplit()) { + throw new IllegalStateException("Can not split a box with only 1 color"); + } + + // find median along the longest dimension + final int splitPoint = findSplitPoint(); + + Vbox newBox = new Vbox(splitPoint + 1, mUpperIndex); + + // Now change this box's upperIndex and recompute the color boundaries + mUpperIndex = splitPoint; + fitBox(); + + return newBox; + } + + /** + * @return the dimension which this box is largest in + */ + final int getLongestColorDimension() { + final int redLength = mMaxRed - mMinRed; + final int greenLength = mMaxGreen - mMinGreen; + final int blueLength = mMaxBlue - mMinBlue; + + if (redLength >= greenLength && redLength >= blueLength) { + return COMPONENT_RED; + } else if (greenLength >= redLength && greenLength >= blueLength) { + return COMPONENT_GREEN; + } else { + return COMPONENT_BLUE; + } + } + + /** + * Finds the point within this box's lowerIndex and upperIndex index of where to split. + * + * This is calculated by finding the longest color dimension, and then sorting the + * sub-array based on that dimension value in each color. The colors are then iterated over + * until a color is found with at least the midpoint of the whole box's dimension midpoint. + * + * @return the index of the colors array to split from + */ + final int findSplitPoint() { + final int longestDimension = getLongestColorDimension(); + final int[] colors = mColors; + final int[] hist = mHistogram; + + // We need to sort the colors in this box based on the longest color dimension. + // As we can't use a Comparator to define the sort logic, we modify each color so that + // it's most significant is the desired dimension + modifySignificantOctet(colors, longestDimension, mLowerIndex, mUpperIndex); + + // Now sort... Arrays.sort uses a exclusive toIndex so we need to add 1 + Arrays.sort(colors, mLowerIndex, mUpperIndex + 1); + + // Now revert all of the colors so that they are packed as RGB again + modifySignificantOctet(colors, longestDimension, mLowerIndex, mUpperIndex); + + final int midPoint = mPopulation / 2; + for (int i = mLowerIndex, count = 0; i <= mUpperIndex; i++) { + count += hist[colors[i]]; + if (count >= midPoint) { + return i; + } + } + + return mLowerIndex; + } + + /** + * @return the average color of this box. + */ + final Swatch getAverageColor() { + final int[] colors = mColors; + final int[] hist = mHistogram; + int redSum = 0; + int greenSum = 0; + int blueSum = 0; + int totalPopulation = 0; + + for (int i = mLowerIndex; i <= mUpperIndex; i++) { + final int color = colors[i]; + final int colorPopulation = hist[color]; + + totalPopulation += colorPopulation; + redSum += colorPopulation * quantizedRed(color); + greenSum += colorPopulation * quantizedGreen(color); + blueSum += colorPopulation * quantizedBlue(color); + } + + final int redMean = Math.round(redSum / (float) totalPopulation); + final int greenMean = Math.round(greenSum / (float) totalPopulation); + final int blueMean = Math.round(blueSum / (float) totalPopulation); + + return new Swatch(approximateToRgb888(redMean, greenMean, blueMean), totalPopulation); + } + } + + /** + * Modify the significant octet in a packed color int. Allows sorting based on the value of a + * single color component. This relies on all components being the same word size. + * + * @see Vbox#findSplitPoint() + */ + private static void modifySignificantOctet(final int[] a, final int dimension, + final int lower, final int upper) { + switch (dimension) { + case COMPONENT_RED: + // Already in RGB, no need to do anything + break; + case COMPONENT_GREEN: + // We need to do a RGB to GRB swap, or vice-versa + for (int i = lower; i <= upper; i++) { + final int color = a[i]; + a[i] = quantizedGreen(color) << (QUANTIZE_WORD_WIDTH + QUANTIZE_WORD_WIDTH) + | quantizedRed(color) << QUANTIZE_WORD_WIDTH + | quantizedBlue(color); + } + break; + case COMPONENT_BLUE: + // We need to do a RGB to BGR swap, or vice-versa + for (int i = lower; i <= upper; i++) { + final int color = a[i]; + a[i] = quantizedBlue(color) << (QUANTIZE_WORD_WIDTH + QUANTIZE_WORD_WIDTH) + | quantizedGreen(color) << QUANTIZE_WORD_WIDTH + | quantizedRed(color); + } + break; + } + } + + private boolean shouldIgnoreColor(int color565) { + final int rgb = approximateToRgb888(color565); + ColorUtils.colorToHSL(rgb, mTempHsl); + return shouldIgnoreColor(rgb, mTempHsl); + } + + private boolean shouldIgnoreColor(Swatch color) { + return shouldIgnoreColor(color.getRgb(), color.getHsl()); + } + + private boolean shouldIgnoreColor(int rgb, float[] hsl) { + if (mFilters != null && mFilters.length > 0) { + for (int i = 0, count = mFilters.length; i < count; i++) { + if (!mFilters[i].isAllowed(rgb, hsl)) { + return true; + } + } + } + return false; + } + + /** + * Comparator which sorts {@link Vbox} instances based on their volume, in descending order + */ + private static final Comparator VBOX_COMPARATOR_VOLUME = new Comparator() { + @Override + public int compare(Vbox lhs, Vbox rhs) { + return rhs.getVolume() - lhs.getVolume(); + } + }; + + /** + * Quantized a RGB888 value to have a word width of {@value #QUANTIZE_WORD_WIDTH}. + */ + private static int quantizeFromRgb888(int color) { + int r = modifyWordWidth(Color.red(color), 8, QUANTIZE_WORD_WIDTH); + int g = modifyWordWidth(Color.green(color), 8, QUANTIZE_WORD_WIDTH); + int b = modifyWordWidth(Color.blue(color), 8, QUANTIZE_WORD_WIDTH); + return r << (QUANTIZE_WORD_WIDTH + QUANTIZE_WORD_WIDTH) | g << QUANTIZE_WORD_WIDTH | b; + } + + /** + * Quantized RGB888 values to have a word width of {@value #QUANTIZE_WORD_WIDTH}. + */ + private static int approximateToRgb888(int r, int g, int b) { + return Color.rgb(modifyWordWidth(r, QUANTIZE_WORD_WIDTH, 8), + modifyWordWidth(g, QUANTIZE_WORD_WIDTH, 8), + modifyWordWidth(b, QUANTIZE_WORD_WIDTH, 8)); + } + + private static int approximateToRgb888(int color) { + return approximateToRgb888(quantizedRed(color), quantizedGreen(color), quantizedBlue(color)); + } + + /** + * @return red component of the quantized color + */ + private static int quantizedRed(int color) { + return (color >> (QUANTIZE_WORD_WIDTH + QUANTIZE_WORD_WIDTH)) & QUANTIZE_WORD_MASK; + } + + /** + * @return green component of a quantized color + */ + private static int quantizedGreen(int color) { + return (color >> QUANTIZE_WORD_WIDTH) & QUANTIZE_WORD_MASK; + } + + /** + * @return blue component of a quantized color + */ + private static int quantizedBlue(int color) { + return color & QUANTIZE_WORD_MASK; + } + + private static int modifyWordWidth(int value, int currentWidth, int targetWidth) { + final int newValue; + if (targetWidth > currentWidth) { + // If we're approximating up in word width, we'll shift up + newValue = value << (targetWidth - currentWidth); + } else { + // Else, we will just shift and keep the MSB + newValue = value >> (currentWidth - targetWidth); + } + return newValue & ((1 << targetWidth) - 1); + } + +} diff --git a/sdk/src/java/lineageos/util/palette/ColorUtils.java b/sdk/src/java/lineageos/util/palette/ColorUtils.java new file mode 100644 index 00000000..7416fb7f --- /dev/null +++ b/sdk/src/java/lineageos/util/palette/ColorUtils.java @@ -0,0 +1,299 @@ +/* + * Copyright 2015 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 lineageos.util.palette; + +import android.graphics.Color; + +/** + * A set of color-related utility methods, building upon those available in {@code Color}. + * + * @hide + */ +public class ColorUtils { + + private static final int MIN_ALPHA_SEARCH_MAX_ITERATIONS = 10; + private static final int MIN_ALPHA_SEARCH_PRECISION = 10; + + private ColorUtils() {} + + /** + * Composite two potentially translucent colors over each other and returns the result. + */ + public static int compositeColors(int foreground, int background) { + int bgAlpha = Color.alpha(background); + int fgAlpha = Color.alpha(foreground); + int a = compositeAlpha(fgAlpha, bgAlpha); + + int r = compositeComponent(Color.red(foreground), fgAlpha, + Color.red(background), bgAlpha, a); + int g = compositeComponent(Color.green(foreground), fgAlpha, + Color.green(background), bgAlpha, a); + int b = compositeComponent(Color.blue(foreground), fgAlpha, + Color.blue(background), bgAlpha, a); + + return Color.argb(a, r, g, b); + } + + private static int compositeAlpha(int foregroundAlpha, int backgroundAlpha) { + return 0xFF - (((0xFF - backgroundAlpha) * (0xFF - foregroundAlpha)) / 0xFF); + } + + private static int compositeComponent(int fgC, int fgA, int bgC, int bgA, int a) { + if (a == 0) return 0; + return ((0xFF * fgC * fgA) + (bgC * bgA * (0xFF - fgA))) / (a * 0xFF); + } + + /** + * Returns the luminance of a color. + * + * Formula defined here: http://www.w3.org/TR/2008/REC-WCAG20-20081211/#relativeluminancedef + */ + public static double calculateLuminance(int color) { + double red = Color.red(color) / 255d; + red = red < 0.03928 ? red / 12.92 : Math.pow((red + 0.055) / 1.055, 2.4); + + double green = Color.green(color) / 255d; + green = green < 0.03928 ? green / 12.92 : Math.pow((green + 0.055) / 1.055, 2.4); + + double blue = Color.blue(color) / 255d; + blue = blue < 0.03928 ? blue / 12.92 : Math.pow((blue + 0.055) / 1.055, 2.4); + + return (0.2126 * red) + (0.7152 * green) + (0.0722 * blue); + } + + /** + * Returns the contrast ratio between {@code foreground} and {@code background}. + * {@code background} must be opaque. + *

+ * Formula defined + * here. + */ + public static double calculateContrast(int foreground, int background) { + if (Color.alpha(background) != 255) { + throw new IllegalArgumentException("background can not be translucent"); + } + if (Color.alpha(foreground) < 255) { + // If the foreground is translucent, composite the foreground over the background + foreground = compositeColors(foreground, background); + } + + final double luminance1 = calculateLuminance(foreground) + 0.05; + final double luminance2 = calculateLuminance(background) + 0.05; + + // Now return the lighter luminance divided by the darker luminance + return Math.max(luminance1, luminance2) / Math.min(luminance1, luminance2); + } + + /** + * Calculates the minimum alpha value which can be applied to {@code foreground} so that would + * have a contrast value of at least {@code minContrastRatio} when compared to + * {@code background}. + * + * @param foreground the foreground color. + * @param background the background color. Should be opaque. + * @param minContrastRatio the minimum contrast ratio. + * @return the alpha value in the range 0-255, or -1 if no value could be calculated. + */ + public static int calculateMinimumAlpha(int foreground, int background, + float minContrastRatio) { + if (Color.alpha(background) != 255) { + throw new IllegalArgumentException("background can not be translucent"); + } + + // First lets check that a fully opaque foreground has sufficient contrast + int testForeground = setAlphaComponent(foreground, 255); + double testRatio = calculateContrast(testForeground, background); + if (testRatio < minContrastRatio) { + // Fully opaque foreground does not have sufficient contrast, return error + return -1; + } + + // Binary search to find a value with the minimum value which provides sufficient contrast + int numIterations = 0; + int minAlpha = 0; + int maxAlpha = 255; + + while (numIterations <= MIN_ALPHA_SEARCH_MAX_ITERATIONS && + (maxAlpha - minAlpha) > MIN_ALPHA_SEARCH_PRECISION) { + final int testAlpha = (minAlpha + maxAlpha) / 2; + + testForeground = setAlphaComponent(foreground, testAlpha); + testRatio = calculateContrast(testForeground, background); + + if (testRatio < minContrastRatio) { + minAlpha = testAlpha; + } else { + maxAlpha = testAlpha; + } + + numIterations++; + } + + // Conservatively return the max of the range of possible alphas, which is known to pass. + return maxAlpha; + } + + /** + * Convert RGB components to HSL (hue-saturation-lightness). + *

    + *
  • hsl[0] is Hue [0 .. 360)
    • + *
  • hsl[1] is Saturation [0...1]
    • + *
  • hsl[2] is Lightness [0...1]
    • + *
+ * + * @param r red component value [0..255] + * @param g green component value [0..255] + * @param b blue component value [0..255] + * @param hsl 3 element array which holds the resulting HSL components. + */ + public static void RGBToHSL(int r, int g, int b, float[] hsl) { + final float rf = r / 255f; + final float gf = g / 255f; + final float bf = b / 255f; + + final float max = Math.max(rf, Math.max(gf, bf)); + final float min = Math.min(rf, Math.min(gf, bf)); + final float deltaMaxMin = max - min; + + float h, s; + float l = (max + min) / 2f; + + if (max == min) { + // Monochromatic + h = s = 0f; + } else { + if (max == rf) { + h = ((gf - bf) / deltaMaxMin) % 6f; + } else if (max == gf) { + h = ((bf - rf) / deltaMaxMin) + 2f; + } else { + h = ((rf - gf) / deltaMaxMin) + 4f; + } + + s = deltaMaxMin / (1f - Math.abs(2f * l - 1f)); + } + + h = (h * 60f) % 360f; + if (h < 0) { + h += 360f; + } + + hsl[0] = constrain(h, 0f, 360f); + hsl[1] = constrain(s, 0f, 1f); + hsl[2] = constrain(l, 0f, 1f); + } + + /** + * Convert the ARGB color to its HSL (hue-saturation-lightness) components. + *
    + *
  • hsl[0] is Hue [0 .. 360)
    • + *
  • hsl[1] is Saturation [0...1]
    • + *
  • hsl[2] is Lightness [0...1]
    • + *
+ * + * @param color the ARGB color to convert. The alpha component is ignored. + * @param hsl 3 element array which holds the resulting HSL components. + */ + public static void colorToHSL(int color, float[] hsl) { + RGBToHSL(Color.red(color), Color.green(color), Color.blue(color), hsl); + } + + /** + * Convert HSL (hue-saturation-lightness) components to a RGB color. + *
    + *
  • hsl[0] is Hue [0 .. 360)
    • + *
  • hsl[1] is Saturation [0...1]
    • + *
  • hsl[2] is Lightness [0...1]
    • + *
+ * If hsv values are out of range, they are pinned. + * + * @param hsl 3 element array which holds the input HSL components. + * @return the resulting RGB color + */ + public static int HSLToColor(float[] hsl) { + final float h = hsl[0]; + final float s = hsl[1]; + final float l = hsl[2]; + + final float c = (1f - Math.abs(2 * l - 1f)) * s; + final float m = l - 0.5f * c; + final float x = c * (1f - Math.abs((h / 60f % 2f) - 1f)); + + final int hueSegment = (int) h / 60; + + int r = 0, g = 0, b = 0; + + switch (hueSegment) { + case 0: + r = Math.round(255 * (c + m)); + g = Math.round(255 * (x + m)); + b = Math.round(255 * m); + break; + case 1: + r = Math.round(255 * (x + m)); + g = Math.round(255 * (c + m)); + b = Math.round(255 * m); + break; + case 2: + r = Math.round(255 * m); + g = Math.round(255 * (c + m)); + b = Math.round(255 * (x + m)); + break; + case 3: + r = Math.round(255 * m); + g = Math.round(255 * (x + m)); + b = Math.round(255 * (c + m)); + break; + case 4: + r = Math.round(255 * (x + m)); + g = Math.round(255 * m); + b = Math.round(255 * (c + m)); + break; + case 5: + case 6: + r = Math.round(255 * (c + m)); + g = Math.round(255 * m); + b = Math.round(255 * (x + m)); + break; + } + + r = constrain(r, 0, 255); + g = constrain(g, 0, 255); + b = constrain(b, 0, 255); + + return Color.rgb(r, g, b); + } + + /** + * Set the alpha component of {@code color} to be {@code alpha}. + */ + public static int setAlphaComponent(int color, int alpha) { + if (alpha < 0 || alpha > 255) { + throw new IllegalArgumentException("alpha must be between 0 and 255."); + } + return (color & 0x00ffffff) | (alpha << 24); + } + + private static float constrain(float amount, float low, float high) { + return amount < low ? low : (amount > high ? high : amount); + } + + private static int constrain(int amount, int low, int high) { + return amount < low ? low : (amount > high ? high : amount); + } + +} diff --git a/sdk/src/java/lineageos/util/palette/DefaultGenerator.java b/sdk/src/java/lineageos/util/palette/DefaultGenerator.java new file mode 100644 index 00000000..0cf2e235 --- /dev/null +++ b/sdk/src/java/lineageos/util/palette/DefaultGenerator.java @@ -0,0 +1,244 @@ +/* + * Copyright 2015 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 lineageos.util.palette; + +import lineageos.util.palette.Palette.Swatch; + +import java.util.List; + +/** + * @hide + */ +class DefaultGenerator extends Palette.Generator { + + private static final float TARGET_DARK_LUMA = 0.26f; + private static final float MAX_DARK_LUMA = 0.45f; + + private static final float MIN_LIGHT_LUMA = 0.55f; + private static final float TARGET_LIGHT_LUMA = 0.74f; + + private static final float MIN_NORMAL_LUMA = 0.3f; + private static final float TARGET_NORMAL_LUMA = 0.5f; + private static final float MAX_NORMAL_LUMA = 0.7f; + + private static final float TARGET_MUTED_SATURATION = 0.3f; + private static final float MAX_MUTED_SATURATION = 0.4f; + + private static final float TARGET_VIBRANT_SATURATION = 1f; + private static final float MIN_VIBRANT_SATURATION = 0.35f; + + private static final float WEIGHT_SATURATION = 3f; + private static final float WEIGHT_LUMA = 6f; + private static final float WEIGHT_POPULATION = 1f; + + private List mSwatches; + + private int mHighestPopulation; + + private Swatch mVibrantSwatch; + private Swatch mMutedSwatch; + private Swatch mDarkVibrantSwatch; + private Swatch mDarkMutedSwatch; + private Swatch mLightVibrantSwatch; + private Swatch mLightMutedSwatch; + + @Override + public void generate(final List swatches) { + mSwatches = swatches; + + mHighestPopulation = findMaxPopulation(); + + generateVariationColors(); + + // Now try and generate any missing colors + generateEmptySwatches(); + } + + @Override + public Swatch getVibrantSwatch() { + return mVibrantSwatch; + } + + @Override + public Swatch getLightVibrantSwatch() { + return mLightVibrantSwatch; + } + + @Override + public Swatch getDarkVibrantSwatch() { + return mDarkVibrantSwatch; + } + + @Override + public Swatch getMutedSwatch() { + return mMutedSwatch; + } + + @Override + public Swatch getLightMutedSwatch() { + return mLightMutedSwatch; + } + + @Override + public Swatch getDarkMutedSwatch() { + return mDarkMutedSwatch; + } + + private void generateVariationColors() { + mVibrantSwatch = findColorVariation(TARGET_NORMAL_LUMA, MIN_NORMAL_LUMA, MAX_NORMAL_LUMA, + TARGET_VIBRANT_SATURATION, MIN_VIBRANT_SATURATION, 1f); + + mLightVibrantSwatch = findColorVariation(TARGET_LIGHT_LUMA, MIN_LIGHT_LUMA, 1f, + TARGET_VIBRANT_SATURATION, MIN_VIBRANT_SATURATION, 1f); + + mDarkVibrantSwatch = findColorVariation(TARGET_DARK_LUMA, 0f, MAX_DARK_LUMA, + TARGET_VIBRANT_SATURATION, MIN_VIBRANT_SATURATION, 1f); + + mMutedSwatch = findColorVariation(TARGET_NORMAL_LUMA, MIN_NORMAL_LUMA, MAX_NORMAL_LUMA, + TARGET_MUTED_SATURATION, 0f, MAX_MUTED_SATURATION); + + mLightMutedSwatch = findColorVariation(TARGET_LIGHT_LUMA, MIN_LIGHT_LUMA, 1f, + TARGET_MUTED_SATURATION, 0f, MAX_MUTED_SATURATION); + + mDarkMutedSwatch = findColorVariation(TARGET_DARK_LUMA, 0f, MAX_DARK_LUMA, + TARGET_MUTED_SATURATION, 0f, MAX_MUTED_SATURATION); + } + + /** + * Try and generate any missing swatches from the swatches we did find. + */ + private void generateEmptySwatches() { + if (mVibrantSwatch == null) { + // If we do not have a vibrant color... + if (mDarkVibrantSwatch != null) { + // ...but we do have a dark vibrant, generate the value by modifying the luma + final float[] newHsl = copyHslValues(mDarkVibrantSwatch); + newHsl[2] = TARGET_NORMAL_LUMA; + mVibrantSwatch = new Swatch(ColorUtils.HSLToColor(newHsl), 0); + } + } + + if (mDarkVibrantSwatch == null) { + // If we do not have a dark vibrant color... + if (mVibrantSwatch != null) { + // ...but we do have a vibrant, generate the value by modifying the luma + final float[] newHsl = copyHslValues(mVibrantSwatch); + newHsl[2] = TARGET_DARK_LUMA; + mDarkVibrantSwatch = new Swatch(ColorUtils.HSLToColor(newHsl), 0); + } + } + } + + /** + * Find the {@link Palette.Swatch} with the highest population value and return the population. + */ + private int findMaxPopulation() { + int population = 0; + for (Swatch swatch : mSwatches) { + population = Math.max(population, swatch.getPopulation()); + } + return population; + } + + private Swatch findColorVariation(float targetLuma, float minLuma, float maxLuma, + float targetSaturation, float minSaturation, float maxSaturation) { + Swatch max = null; + float maxValue = 0f; + + for (Swatch swatch : mSwatches) { + final float sat = swatch.getHsl()[1]; + final float luma = swatch.getHsl()[2]; + + if (sat >= minSaturation && sat <= maxSaturation && + luma >= minLuma && luma <= maxLuma && + !isAlreadySelected(swatch)) { + float value = createComparisonValue(sat, targetSaturation, luma, targetLuma, + swatch.getPopulation(), mHighestPopulation); + if (max == null || value > maxValue) { + max = swatch; + maxValue = value; + } + } + } + + return max; + } + + /** + * @return true if we have already selected {@code swatch} + */ + private boolean isAlreadySelected(Swatch swatch) { + return mVibrantSwatch == swatch || mDarkVibrantSwatch == swatch || + mLightVibrantSwatch == swatch || mMutedSwatch == swatch || + mDarkMutedSwatch == swatch || mLightMutedSwatch == swatch; + } + + private static float createComparisonValue(float saturation, float targetSaturation, + float luma, float targetLuma, + int population, int maxPopulation) { + return createComparisonValue(saturation, targetSaturation, WEIGHT_SATURATION, + luma, targetLuma, WEIGHT_LUMA, + population, maxPopulation, WEIGHT_POPULATION); + } + + private static float createComparisonValue( + float saturation, float targetSaturation, float saturationWeight, + float luma, float targetLuma, float lumaWeight, + int population, int maxPopulation, float populationWeight) { + return weightedMean( + invertDiff(saturation, targetSaturation), saturationWeight, + invertDiff(luma, targetLuma), lumaWeight, + population / (float) maxPopulation, populationWeight + ); + } + + /** + * Copy a {@link Swatch}'s HSL values into a new float[]. + */ + private static float[] copyHslValues(Swatch color) { + final float[] newHsl = new float[3]; + System.arraycopy(color.getHsl(), 0, newHsl, 0, 3); + return newHsl; + } + + /** + * Returns a value in the range 0-1. 1 is returned when {@code value} equals the + * {@code targetValue} and then decreases as the absolute difference between {@code value} and + * {@code targetValue} increases. + * + * @param value the item's value + * @param targetValue the value which we desire + */ + private static float invertDiff(float value, float targetValue) { + return 1f - Math.abs(value - targetValue); + } + + private static float weightedMean(float... values) { + float sum = 0f; + float sumWeight = 0f; + + for (int i = 0; i < values.length; i += 2) { + float value = values[i]; + float weight = values[i + 1]; + + sum += (value * weight); + sumWeight += weight; + } + + return sum / sumWeight; + } +} diff --git a/sdk/src/java/lineageos/util/palette/Palette.java b/sdk/src/java/lineageos/util/palette/Palette.java new file mode 100644 index 00000000..cf960dda --- /dev/null +++ b/sdk/src/java/lineageos/util/palette/Palette.java @@ -0,0 +1,740 @@ +/* + * Copyright 2014 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 lineageos.util.palette; + +import android.graphics.Bitmap; +import android.graphics.Color; +import android.os.AsyncTask; +import android.annotation.ColorInt; +import android.annotation.Nullable; +import android.util.TimingLogger; + +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Collections; +import java.util.List; + +/** + * A helper class to extract prominent colors from an image. + *

+ * A number of colors with different profiles are extracted from the image: + *

    + *
  • Vibrant
    • + *
  • Vibrant Dark
    • + *
  • Vibrant Light
    • + *
  • Muted
    • + *
  • Muted Dark
    • + *
  • Muted Light
    • + *
+ * These can be retrieved from the appropriate getter method. + * + *

+ * Instances are created with a {@link Builder} which supports several options to tweak the + * generated Palette. See that class' documentation for more information. + *

+ * Generation should always be completed on a background thread, ideally the one in + * which you load your image on. {@link Builder} supports both synchronous and asynchronous + * generation: + * + * 

+ * // Synchronous
+ * Palette p = Palette.from(bitmap).generate();
+ *
+ * // Asynchronous
+ * Palette.from(bitmap).generate(new PaletteAsyncListener() {
+ *     public void onGenerated(Palette p) {
+ *         // Use generated instance
+ *     }
+ * });
+ *
+ * + * @hide + */ +public final class Palette { + + /** + * Listener to be used with {@link #generateAsync(Bitmap, PaletteAsyncListener)} or + * {@link #generateAsync(Bitmap, int, PaletteAsyncListener)} + */ + public interface PaletteAsyncListener { + + /** + * Called when the {@link Palette} has been generated. + */ + void onGenerated(Palette palette); + } + + private static final int DEFAULT_RESIZE_BITMAP_MAX_DIMENSION = 192; + private static final int DEFAULT_CALCULATE_NUMBER_COLORS = 16; + + private static final float MIN_CONTRAST_TITLE_TEXT = 3.0f; + private static final float MIN_CONTRAST_BODY_TEXT = 4.5f; + + private static final String LOG_TAG = "Palette"; + private static final boolean LOG_TIMINGS = false; + + /** + * Start generating a {@link Palette} with the returned {@link Builder} instance. + */ + public static Builder from(Bitmap bitmap) { + return new Builder(bitmap); + } + + /** + * Generate a {@link Palette} from the pre-generated list of {@link Palette.Swatch} swatches. + * This is useful for testing, or if you want to resurrect a {@link Palette} instance from a + * list of swatches. Will return null if the {@code swatches} is null. + */ + public static Palette from(List swatches) { + return new Builder(swatches).generate(); + } + + /** + * @deprecated Use {@link Builder} to generate the Palette. + */ + @Deprecated + public static Palette generate(Bitmap bitmap) { + return from(bitmap).generate(); + } + + /** + * @deprecated Use {@link Builder} to generate the Palette. + */ + @Deprecated + public static Palette generate(Bitmap bitmap, int numColors) { + return from(bitmap).maximumColorCount(numColors).generate(); + } + + /** + * @deprecated Use {@link Builder} to generate the Palette. + */ + @Deprecated + public static AsyncTask generateAsync( + Bitmap bitmap, PaletteAsyncListener listener) { + return from(bitmap).generate(listener); + } + + /** + * @deprecated Use {@link Builder} to generate the Palette. + */ + @Deprecated + public static AsyncTask generateAsync( + final Bitmap bitmap, final int numColors, final PaletteAsyncListener listener) { + return from(bitmap).maximumColorCount(numColors).generate(listener); + } + + private final List mSwatches; + private final Generator mGenerator; + + private Palette(List swatches, Generator generator) { + mSwatches = swatches; + mGenerator = generator; + } + + /** + * Returns all of the swatches which make up the palette. + */ + public List getSwatches() { + return Collections.unmodifiableList(mSwatches); + } + + /** + * Returns the most vibrant swatch in the palette. Might be null. + */ + @Nullable + public Swatch getVibrantSwatch() { + return mGenerator.getVibrantSwatch(); + } + + /** + * Returns a light and vibrant swatch from the palette. Might be null. + */ + @Nullable + public Swatch getLightVibrantSwatch() { + return mGenerator.getLightVibrantSwatch(); + } + + /** + * Returns a dark and vibrant swatch from the palette. Might be null. + */ + @Nullable + public Swatch getDarkVibrantSwatch() { + return mGenerator.getDarkVibrantSwatch(); + } + + /** + * Returns a muted swatch from the palette. Might be null. + */ + @Nullable + public Swatch getMutedSwatch() { + return mGenerator.getMutedSwatch(); + } + + /** + * Returns a muted and light swatch from the palette. Might be null. + */ + @Nullable + public Swatch getLightMutedSwatch() { + return mGenerator.getLightMutedSwatch(); + } + + /** + * Returns a muted and dark swatch from the palette. Might be null. + */ + @Nullable + public Swatch getDarkMutedSwatch() { + return mGenerator.getDarkMutedSwatch(); + } + + /** + * Returns the most vibrant color in the palette as an RGB packed int. + * + * @param defaultColor value to return if the swatch isn't available + */ + @ColorInt + public int getVibrantColor(@ColorInt int defaultColor) { + Swatch swatch = getVibrantSwatch(); + return swatch != null ? swatch.getRgb() : defaultColor; + } + + /** + * Returns a light and vibrant color from the palette as an RGB packed int. + * + * @param defaultColor value to return if the swatch isn't available + */ + @ColorInt + public int getLightVibrantColor(@ColorInt int defaultColor) { + Swatch swatch = getLightVibrantSwatch(); + return swatch != null ? swatch.getRgb() : defaultColor; + } + + /** + * Returns a dark and vibrant color from the palette as an RGB packed int. + * + * @param defaultColor value to return if the swatch isn't available + */ + @ColorInt + public int getDarkVibrantColor(@ColorInt int defaultColor) { + Swatch swatch = getDarkVibrantSwatch(); + return swatch != null ? swatch.getRgb() : defaultColor; + } + + /** + * Returns a muted color from the palette as an RGB packed int. + * + * @param defaultColor value to return if the swatch isn't available + */ + @ColorInt + public int getMutedColor(@ColorInt int defaultColor) { + Swatch swatch = getMutedSwatch(); + return swatch != null ? swatch.getRgb() : defaultColor; + } + + /** + * Returns a muted and light color from the palette as an RGB packed int. + * + * @param defaultColor value to return if the swatch isn't available + */ + @ColorInt + public int getLightMutedColor(@ColorInt int defaultColor) { + Swatch swatch = getLightMutedSwatch(); + return swatch != null ? swatch.getRgb() : defaultColor; + } + + /** + * Returns a muted and dark color from the palette as an RGB packed int. + * + * @param defaultColor value to return if the swatch isn't available + */ + @ColorInt + public int getDarkMutedColor(@ColorInt int defaultColor) { + Swatch swatch = getDarkMutedSwatch(); + return swatch != null ? swatch.getRgb() : defaultColor; + } + + /** + * Scale the bitmap down so that it's largest dimension is {@code targetMaxDimension}. + * If {@code bitmap} is smaller than this, then it is returned. + */ + private static Bitmap scaleBitmapDown(Bitmap bitmap, final int targetMaxDimension) { + final int maxDimension = Math.max(bitmap.getWidth(), bitmap.getHeight()); + + if (maxDimension <= targetMaxDimension) { + // If the bitmap is small enough already, just return it + return bitmap; + } + + final float scaleRatio = targetMaxDimension / (float) maxDimension; + return Bitmap.createScaledBitmap(bitmap, + Math.round(bitmap.getWidth() * scaleRatio), + Math.round(bitmap.getHeight() * scaleRatio), + false); + } + + /** + * Represents a color swatch generated from an image's palette. The RGB color can be retrieved + * by calling {@link #getRgb()}. + */ + public static final class Swatch { + private final int mRed, mGreen, mBlue; + private final int mRgb; + private final int mPopulation; + + private boolean mGeneratedTextColors; + private int mTitleTextColor; + private int mBodyTextColor; + + private float[] mHsl; + + public Swatch(@ColorInt int color, int population) { + mRed = Color.red(color); + mGreen = Color.green(color); + mBlue = Color.blue(color); + mRgb = color; + mPopulation = population; + } + + Swatch(int red, int green, int blue, int population) { + mRed = red; + mGreen = green; + mBlue = blue; + mRgb = Color.rgb(red, green, blue); + mPopulation = population; + } + + /** + * @return this swatch's RGB color value + */ + @ColorInt + public int getRgb() { + return mRgb; + } + + /** + * Return this swatch's HSL values. + * hsv[0] is Hue [0 .. 360) + * hsv[1] is Saturation [0...1] + * hsv[2] is Lightness [0...1] + */ + public float[] getHsl() { + if (mHsl == null) { + mHsl = new float[3]; + ColorUtils.RGBToHSL(mRed, mGreen, mBlue, mHsl); + } + return mHsl; + } + + /** + * @return the number of pixels represented by this swatch + */ + public int getPopulation() { + return mPopulation; + } + + /** + * Returns an appropriate color to use for any 'title' text which is displayed over this + * {@link Swatch}'s color. This color is guaranteed to have sufficient contrast. + */ + @ColorInt + public int getTitleTextColor() { + ensureTextColorsGenerated(); + return mTitleTextColor; + } + + /** + * Returns an appropriate color to use for any 'body' text which is displayed over this + * {@link Swatch}'s color. This color is guaranteed to have sufficient contrast. + */ + @ColorInt + public int getBodyTextColor() { + ensureTextColorsGenerated(); + return mBodyTextColor; + } + + private void ensureTextColorsGenerated() { + if (!mGeneratedTextColors) { + // First check white, as most colors will be dark + final int lightBodyAlpha = ColorUtils.calculateMinimumAlpha( + Color.WHITE, mRgb, MIN_CONTRAST_BODY_TEXT); + final int lightTitleAlpha = ColorUtils.calculateMinimumAlpha( + Color.WHITE, mRgb, MIN_CONTRAST_TITLE_TEXT); + + if (lightBodyAlpha != -1 && lightTitleAlpha != -1) { + // If we found valid light values, use them and return + mBodyTextColor = ColorUtils.setAlphaComponent(Color.WHITE, lightBodyAlpha); + mTitleTextColor = ColorUtils.setAlphaComponent(Color.WHITE, lightTitleAlpha); + mGeneratedTextColors = true; + return; + } + + final int darkBodyAlpha = ColorUtils.calculateMinimumAlpha( + Color.BLACK, mRgb, MIN_CONTRAST_BODY_TEXT); + final int darkTitleAlpha = ColorUtils.calculateMinimumAlpha( + Color.BLACK, mRgb, MIN_CONTRAST_TITLE_TEXT); + + if (darkBodyAlpha != -1 && darkBodyAlpha != -1) { + // If we found valid dark values, use them and return + mBodyTextColor = ColorUtils.setAlphaComponent(Color.BLACK, darkBodyAlpha); + mTitleTextColor = ColorUtils.setAlphaComponent(Color.BLACK, darkTitleAlpha); + mGeneratedTextColors = true; + return; + } + + // If we reach here then we can not find title and body values which use the same + // lightness, we need to use mismatched values + mBodyTextColor = lightBodyAlpha != -1 + ? ColorUtils.setAlphaComponent(Color.WHITE, lightBodyAlpha) + : ColorUtils.setAlphaComponent(Color.BLACK, darkBodyAlpha); + mTitleTextColor = lightTitleAlpha != -1 + ? ColorUtils.setAlphaComponent(Color.WHITE, lightTitleAlpha) + : ColorUtils.setAlphaComponent(Color.BLACK, darkTitleAlpha); + mGeneratedTextColors = true; + } + } + + @Override + public String toString() { + return new StringBuilder(getClass().getSimpleName()) + .append(" [RGB: #").append(Integer.toHexString(getRgb())).append(']') + .append(" [HSL: ").append(Arrays.toString(getHsl())).append(']') + .append(" [Population: ").append(mPopulation).append(']') + .append(" [Title Text: #").append(Integer.toHexString(getTitleTextColor())) + .append(']') + .append(" [Body Text: #").append(Integer.toHexString(getBodyTextColor())) + .append(']').toString(); + } + + @Override + public boolean equals(Object o) { + if (this == o) { + return true; + } + if (o == null || getClass() != o.getClass()) { + return false; + } + + Swatch swatch = (Swatch) o; + return mPopulation == swatch.mPopulation && mRgb == swatch.mRgb; + } + + @Override + public int hashCode() { + return 31 * mRgb + mPopulation; + } + } + + /** + * Builder class for generating {@link Palette} instances. + */ + public static final class Builder { + private List mSwatches; + private Bitmap mBitmap; + private int mMaxColors = DEFAULT_CALCULATE_NUMBER_COLORS; + private int mResizeMaxDimension = DEFAULT_RESIZE_BITMAP_MAX_DIMENSION; + private final List mFilters = new ArrayList<>(); + + private Generator mGenerator; + + /** + * Construct a new {@link Builder} using a source {@link Bitmap} + */ + public Builder(Bitmap bitmap) { + this(); + if (bitmap == null || bitmap.isRecycled()) { + throw new IllegalArgumentException("Bitmap is not valid"); + } + mBitmap = bitmap; + } + + /** + * Construct a new {@link Builder} using a list of {@link Swatch} instances. + * Typically only used for testing. + */ + public Builder(List swatches) { + this(); + if (swatches == null || swatches.isEmpty()) { + throw new IllegalArgumentException("List of Swatches is not valid"); + } + mSwatches = swatches; + } + + private Builder() { + mFilters.add(DEFAULT_FILTER); + } + + /** + * Set the {@link Generator} to use when generating the {@link Palette}. If this is called + * with {@code null} then the default generator will be used. + */ + Builder generator(Generator generator) { + mGenerator = generator; + return this; + } + + /** + * Set the maximum number of colors to use in the quantization step when using a + * {@link android.graphics.Bitmap} as the source. + *

+ * Good values for depend on the source image type. For landscapes, good values are in + * the range 10-16. For images which are largely made up of people's faces then this + * value should be increased to ~24. + */ + public Builder maximumColorCount(int colors) { + mMaxColors = colors; + return this; + } + + /** + * Set the resize value when using a {@link android.graphics.Bitmap} as the source. + * If the bitmap's largest dimension is greater than the value specified, then the bitmap + * will be resized so that it's largest dimension matches {@code maxDimension}. If the + * bitmap is smaller or equal, the original is used as-is. + *

+ * This value has a large effect on the processing time. The larger the resized image is, + * the greater time it will take to generate the palette. The smaller the image is, the + * more detail is lost in the resulting image and thus less precision for color selection. + */ + public Builder resizeBitmapSize(int maxDimension) { + mResizeMaxDimension = maxDimension; + return this; + } + + /** + * Clear all added filters. This includes any default filters added automatically by + * {@link Palette}. + */ + public Builder clearFilters() { + mFilters.clear(); + return this; + } + + /** + * Add a filter to be able to have fine grained controlled over the colors which are + * allowed in the resulting palette. + * + * @param filter filter to add. + */ + public Builder addFilter(Filter filter) { + if (filter != null) { + mFilters.add(filter); + } + return this; + } + + /** + * Generate and return the {@link Palette} synchronously. + */ + public Palette generate() { + final TimingLogger logger = LOG_TIMINGS + ? new TimingLogger(LOG_TAG, "Generation") + : null; + + List swatches; + + if (mBitmap != null) { + // We have a Bitmap so we need to quantization to reduce the number of colors + + if (mResizeMaxDimension <= 0) { + throw new IllegalArgumentException( + "Minimum dimension size for resizing should should be >= 1"); + } + + // First we'll scale down the bitmap so it's largest dimension is as specified + final Bitmap scaledBitmap = scaleBitmapDown(mBitmap, mResizeMaxDimension); + + if (logger != null) { + logger.addSplit("Processed Bitmap"); + } + + // Now generate a quantizer from the Bitmap + final int width = scaledBitmap.getWidth(); + final int height = scaledBitmap.getHeight(); + final int[] pixels = new int[width * height]; + scaledBitmap.getPixels(pixels, 0, width, 0, 0, width, height); + + final ColorCutQuantizer quantizer = new ColorCutQuantizer(pixels, mMaxColors, + mFilters.isEmpty() ? null : mFilters.toArray(new Filter[mFilters.size()])); + + // If created a new bitmap, recycle it + if (scaledBitmap != mBitmap) { + scaledBitmap.recycle(); + } + swatches = quantizer.getQuantizedColors(); + + if (logger != null) { + logger.addSplit("Color quantization completed"); + } + } else { + // Else we're using the provided swatches + swatches = mSwatches; + } + + // If we haven't been provided with a generator, use the default + if (mGenerator == null) { + mGenerator = new DefaultGenerator(); + } + + // Now call let the Generator do it's thing + mGenerator.generate(swatches); + + if (logger != null) { + logger.addSplit("Generator.generate() completed"); + } + + // Now create a Palette instance + Palette p = new Palette(swatches, mGenerator); + + if (logger != null) { + logger.addSplit("Created Palette"); + logger.dumpToLog(); + } + + return p; + } + + /** + * Generate the {@link Palette} asynchronously. The provided listener's + * {@link PaletteAsyncListener#onGenerated} method will be called with the palette when + * generated. + */ + public AsyncTask generate(final PaletteAsyncListener listener) { + if (listener == null) { + throw new IllegalArgumentException("listener can not be null"); + } + + AsyncTask task = new AsyncTask() { + @Override + protected Palette doInBackground(Bitmap... params) { + return generate(); + } + + @Override + protected void onPostExecute(Palette colorExtractor) { + listener.onGenerated(colorExtractor); + } + }; + task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, mBitmap); + return task; + } + } + + static abstract class Generator { + + /** + * This method will be called with the {@link Palette.Swatch} that represent an image. + * You should process this list so that you have appropriate values when the other methods in + * class are called. + *

+ * This method will probably be called on a background thread. + */ + public abstract void generate(List swatches); + + /** + * Return the most vibrant {@link Palette.Swatch} + */ + public Palette.Swatch getVibrantSwatch() { + return null; + } + + /** + * Return a light and vibrant {@link Palette.Swatch} + */ + public Palette.Swatch getLightVibrantSwatch() { + return null; + } + + /** + * Return a dark and vibrant {@link Palette.Swatch} + */ + public Palette.Swatch getDarkVibrantSwatch() { + return null; + } + + /** + * Return a muted {@link Palette.Swatch} + */ + public Palette.Swatch getMutedSwatch() { + return null; + } + + /** + * Return a muted and light {@link Palette.Swatch} + */ + public Palette.Swatch getLightMutedSwatch() { + return null; + } + + /** + * Return a muted and dark {@link Palette.Swatch} + */ + public Palette.Swatch getDarkMutedSwatch() { + return null; + } + } + + /** + * A Filter provides a mechanism for exercising fine-grained control over which colors + * are valid within a resulting {@link Palette}. + */ + public interface Filter { + /** + * Hook to allow clients to be able filter colors from resulting palette. + * + * @param rgb the color in RGB888. + * @param hsl HSL representation of the color. + * + * @return true if the color is allowed, false if not. + * + * @see Builder#addFilter(Filter) + */ + boolean isAllowed(int rgb, float[] hsl); + } + + /** + * The default filter. + */ + private static final Filter DEFAULT_FILTER = new Filter() { + private static final float BLACK_MAX_LIGHTNESS = 0.05f; + private static final float WHITE_MIN_LIGHTNESS = 0.95f; + + @Override + public boolean isAllowed(int rgb, float[] hsl) { + return !isWhite(hsl) && !isBlack(hsl) && !isNearRedILine(hsl); + } + + /** + * @return true if the color represents a color which is close to black. + */ + private boolean isBlack(float[] hslColor) { + return hslColor[2] <= BLACK_MAX_LIGHTNESS; + } + + /** + * @return true if the color represents a color which is close to white. + */ + private boolean isWhite(float[] hslColor) { + return hslColor[2] >= WHITE_MIN_LIGHTNESS; + } + + /** + * @return true if the color lies close to the red side of the I line. + */ + private boolean isNearRedILine(float[] hslColor) { + return hslColor[0] >= 10f && hslColor[0] <= 37f && hslColor[1] <= 0.82f; + } + }; +}