replicant-vendor_cmsdk/sdk/src/java/cyanogenmod/util/ColorUtils.java

527 lines
21 KiB
Java

/*
* Copyright (c) 2011-2016 The CyanogenMod 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 cyanogenmod.util;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.MathUtils;
import com.android.internal.util.cm.palette.Palette;
import java.util.Collections;
import java.util.Comparator;
/**
* Helper class for colorspace conversions, and color-related
* algorithms which may be generally useful.
*/
public class ColorUtils {
private static int[] SOLID_COLORS = new int[] {
Color.RED, 0xFFFFA500, Color.YELLOW, Color.GREEN, Color.CYAN,
Color.BLUE, Color.MAGENTA, Color.WHITE, Color.BLACK
};
/**
* Drop the alpha component from an RGBA packed int and return
* a non sign-extended RGB int.
*
* @param rgba
* @return rgb
*/
public static int dropAlpha(int rgba) {
return rgba & 0x00FFFFFF;
}
/**
* Converts an RGB packed int into L*a*b space, which is well-suited for finding
* perceptual differences in color
*
* @param rgb A 32-bit value of packed RGB ints
* @return array of Lab values of size 3
*/
public static float[] convertRGBtoLAB(int rgb) {
float[] lab = new float[3];
float fx, fy, fz;
float eps = 216.f / 24389.f;
float k = 24389.f / 27.f;
float Xr = 0.964221f; // reference white D50
float Yr = 1.0f;
float Zr = 0.825211f;
// RGB to XYZ
float r = Color.red(rgb) / 255.f; //R 0..1
float g = Color.green(rgb) / 255.f; //G 0..1
float b = Color.blue(rgb) / 255.f; //B 0..1
// assuming sRGB (D65)
if (r <= 0.04045)
r = r / 12;
else
r = (float) Math.pow((r + 0.055) / 1.055, 2.4);
if (g <= 0.04045)
g = g / 12;
else
g = (float) Math.pow((g + 0.055) / 1.055, 2.4);
if (b <= 0.04045)
b = b / 12;
else
b = (float) Math.pow((b + 0.055) / 1.055, 2.4);
float X = 0.436052025f * r + 0.385081593f * g + 0.143087414f * b;
float Y = 0.222491598f * r + 0.71688606f * g + 0.060621486f * b;
float Z = 0.013929122f * r + 0.097097002f * g + 0.71418547f * b;
// XYZ to Lab
float xr = X / Xr;
float yr = Y / Yr;
float zr = Z / Zr;
if (xr > eps)
fx = (float) Math.pow(xr, 1 / 3.);
else
fx = (float) ((k * xr + 16.) / 116.);
if (yr > eps)
fy = (float) Math.pow(yr, 1 / 3.);
else
fy = (float) ((k * yr + 16.) / 116.);
if (zr > eps)
fz = (float) Math.pow(zr, 1 / 3.);
else
fz = (float) ((k * zr + 16.) / 116);
float Ls = (116 * fy) - 16;
float as = 500 * (fx - fy);
float bs = 200 * (fy - fz);
lab[0] = (2.55f * Ls + .5f);
lab[1] = (as + .5f);
lab[2] = (bs + .5f);
return lab;
}
/**
* Calculate the colour difference value between two colours in lab space.
* This code is from OpenIMAJ under BSD License
*
* @param L1 first colour's L component
* @param a1 first colour's a component
* @param b1 first colour's b component
* @param L2 second colour's L component
* @param a2 second colour's a component
* @param b2 second colour's b component
* @return the CIE 2000 colour difference
*/
public static double calculateDeltaE(double L1, double a1, double b1,
double L2, double a2, double b2) {
double Lmean = (L1 + L2) / 2.0;
double C1 = Math.sqrt(a1 * a1 + b1 * b1);
double C2 = Math.sqrt(a2 * a2 + b2 * b2);
double Cmean = (C1 + C2) / 2.0;
double G = (1 - Math.sqrt(Math.pow(Cmean, 7) / (Math.pow(Cmean, 7) + Math.pow(25, 7)))) / 2;
double a1prime = a1 * (1 + G);
double a2prime = a2 * (1 + G);
double C1prime = Math.sqrt(a1prime * a1prime + b1 * b1);
double C2prime = Math.sqrt(a2prime * a2prime + b2 * b2);
double Cmeanprime = (C1prime + C2prime) / 2;
double h1prime = Math.atan2(b1, a1prime)
+ 2 * Math.PI * (Math.atan2(b1, a1prime) < 0 ? 1 : 0);
double h2prime = Math.atan2(b2, a2prime)
+ 2 * Math.PI * (Math.atan2(b2, a2prime) < 0 ? 1 : 0);
double Hmeanprime = ((Math.abs(h1prime - h2prime) > Math.PI)
? (h1prime + h2prime + 2 * Math.PI) / 2 : (h1prime + h2prime) / 2);
double T = 1.0 - 0.17 * Math.cos(Hmeanprime - Math.PI / 6.0)
+ 0.24 * Math.cos(2 * Hmeanprime) + 0.32 * Math.cos(3 * Hmeanprime + Math.PI / 30)
- 0.2 * Math.cos(4 * Hmeanprime - 21 * Math.PI / 60);
double deltahprime = ((Math.abs(h1prime - h2prime) <= Math.PI) ? h2prime - h1prime
: (h2prime <= h1prime) ? h2prime - h1prime + 2 * Math.PI
: h2prime - h1prime - 2 * Math.PI);
double deltaLprime = L2 - L1;
double deltaCprime = C2prime - C1prime;
double deltaHprime = 2.0 * Math.sqrt(C1prime * C2prime) * Math.sin(deltahprime / 2.0);
double SL = 1.0 + ((0.015 * (Lmean - 50) * (Lmean - 50))
/ (Math.sqrt(20 + (Lmean - 50) * (Lmean - 50))));
double SC = 1.0 + 0.045 * Cmeanprime;
double SH = 1.0 + 0.015 * Cmeanprime * T;
double deltaTheta = (30 * Math.PI / 180)
* Math.exp(-((180 / Math.PI * Hmeanprime - 275) / 25)
* ((180 / Math.PI * Hmeanprime - 275) / 25));
double RC = (2
* Math.sqrt(Math.pow(Cmeanprime, 7) / (Math.pow(Cmeanprime, 7) + Math.pow(25, 7))));
double RT = (-RC * Math.sin(2 * deltaTheta));
double KL = 1;
double KC = 1;
double KH = 1;
double deltaE = Math.sqrt(
((deltaLprime / (KL * SL)) * (deltaLprime / (KL * SL))) +
((deltaCprime / (KC * SC)) * (deltaCprime / (KC * SC))) +
((deltaHprime / (KH * SH)) * (deltaHprime / (KH * SH))) +
(RT * (deltaCprime / (KC * SC)) * (deltaHprime / (KH * SH))));
return deltaE;
}
/**
* Finds the "perceptually nearest" color from a list of colors to
* the given RGB value. This is done by converting to
* L*a*b colorspace and using the CIE2000 deltaE algorithm.
*
* @param rgb The original color to start with
* @param colors An array of colors to test
* @return RGB packed int of nearest color in the list
*/
public static int findPerceptuallyNearestColor(int rgb, int[] colors) {
int nearestColor = 0;
double closest = Double.MAX_VALUE;
float[] original = convertRGBtoLAB(rgb);
for (int i = 0; i < colors.length; i++) {
float[] cl = convertRGBtoLAB(colors[i]);
double deltaE = calculateDeltaE(original[0], original[1], original[2],
cl[0], cl[1], cl[2]);
if (deltaE < closest) {
nearestColor = colors[i];
closest = deltaE;
}
}
return nearestColor;
}
/**
* Convenience method to find the nearest "solid" color (having RGB components
* of either 0 or 255) to the given color. This is useful for cases such as
* LED notification lights which may not be able to display the full range
* of colors due to hardware limitations.
*
* @param rgb
* @return the perceptually nearest color in RGB
*/
public static int findPerceptuallyNearestSolidColor(int rgb) {
return findPerceptuallyNearestColor(rgb, SOLID_COLORS);
}
/**
* Given a Palette, pick out the dominant swatch based on population
*
* @param palette
* @return the dominant Swatch
*/
public static Palette.Swatch getDominantSwatch(Palette palette) {
if (palette == null || palette.getSwatches().size() == 0) {
return null;
}
// find most-represented swatch based on population
return Collections.max(palette.getSwatches(), new Comparator<Palette.Swatch>() {
@Override
public int compare(Palette.Swatch sw1, Palette.Swatch sw2) {
return Integer.compare(sw1.getPopulation(), sw2.getPopulation());
}
});
}
/**
* Takes a drawable and uses Palette to generate a suitable "alert"
* color which can be used for an external notification mechanism
* such as an RGB LED. This will always pick a solid color having
* RGB components of 255 or 0.
*
* @param drawable The drawable to generate a color for
* @return a suitable solid color which corresponds to the image
*/
public static int generateAlertColorFromDrawable(Drawable drawable) {
int alertColor = Color.BLACK;
Bitmap bitmap = null;
if (drawable == null) {
return alertColor;
}
if (drawable instanceof BitmapDrawable) {
bitmap = ((BitmapDrawable) drawable).getBitmap();
} else {
bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(),
drawable.getIntrinsicHeight(),
Bitmap.Config.ARGB_8888);
}
if (bitmap != null) {
Palette p = Palette.from(bitmap).generate();
if (p == null) {
return alertColor;
}
// First try the dominant color
final Palette.Swatch dominantSwatch = getDominantSwatch(p);
int iconColor = alertColor;
if (dominantSwatch != null) {
iconColor = dominantSwatch.getRgb();
alertColor = findPerceptuallyNearestSolidColor(iconColor);
}
// Try the most saturated color if we got white or black (boring)
if (alertColor == Color.BLACK || alertColor == Color.WHITE) {
iconColor = p.getVibrantColor(Color.WHITE);
alertColor = findPerceptuallyNearestSolidColor(iconColor);
}
if (!(drawable instanceof BitmapDrawable)) {
bitmap.recycle();
}
}
return alertColor;
}
/**
* Convert a color temperature value (in Kelvin) to a RGB units as floats.
* This can be used in a transform matrix or hardware gamma control.
*
* @param degreesK
* @return array of floats representing rgb values 0->1
*/
public static float[] temperatureToRGB(int degreesK) {
int k = MathUtils.constrain(degreesK, 1000, 20000);
float a = (k % 100) / 100.0f;
int i = ((k - 1000)/ 100) * 3;
return new float[] { interp(i, a), interp(i+1, a), interp(i+2, a) };
}
private static float interp(int i, float a) {
return MathUtils.lerp((float)sColorTable[i], (float)sColorTable[i+3], a);
}
/**
* This table is a modified version of the original blackbody chart, found here:
* http://www.vendian.org/mncharity/dir3/blackbody/UnstableURLs/bbr_color.html
*
* Created by Ingo Thiel.
*/
private static final double[] sColorTable = new double[] {
1.00000000, 0.18172716, 0.00000000,
1.00000000, 0.25503671, 0.00000000,
1.00000000, 0.30942099, 0.00000000,
1.00000000, 0.35357379, 0.00000000,
1.00000000, 0.39091524, 0.00000000,
1.00000000, 0.42322816, 0.00000000,
1.00000000, 0.45159884, 0.00000000,
1.00000000, 0.47675916, 0.00000000,
1.00000000, 0.49923747, 0.00000000,
1.00000000, 0.51943421, 0.00000000,
1.00000000, 0.54360078, 0.08679949,
1.00000000, 0.56618736, 0.14065513,
1.00000000, 0.58734976, 0.18362641,
1.00000000, 0.60724493, 0.22137978,
1.00000000, 0.62600248, 0.25591950,
1.00000000, 0.64373109, 0.28819679,
1.00000000, 0.66052319, 0.31873863,
1.00000000, 0.67645822, 0.34786758,
1.00000000, 0.69160518, 0.37579588,
1.00000000, 0.70602449, 0.40267128,
1.00000000, 0.71976951, 0.42860152,
1.00000000, 0.73288760, 0.45366838,
1.00000000, 0.74542112, 0.47793608,
1.00000000, 0.75740814, 0.50145662,
1.00000000, 0.76888303, 0.52427322,
1.00000000, 0.77987699, 0.54642268,
1.00000000, 0.79041843, 0.56793692,
1.00000000, 0.80053332, 0.58884417,
1.00000000, 0.81024551, 0.60916971,
1.00000000, 0.81957693, 0.62893653,
1.00000000, 0.82854786, 0.64816570,
1.00000000, 0.83717703, 0.66687674,
1.00000000, 0.84548188, 0.68508786,
1.00000000, 0.85347859, 0.70281616,
1.00000000, 0.86118227, 0.72007777,
1.00000000, 0.86860704, 0.73688797,
1.00000000, 0.87576611, 0.75326132,
1.00000000, 0.88267187, 0.76921169,
1.00000000, 0.88933596, 0.78475236,
1.00000000, 0.89576933, 0.79989606,
1.00000000, 0.90198230, 0.81465502,
1.00000000, 0.90963069, 0.82838210,
1.00000000, 0.91710889, 0.84190889,
1.00000000, 0.92441842, 0.85523742,
1.00000000, 0.93156127, 0.86836903,
1.00000000, 0.93853986, 0.88130458,
1.00000000, 0.94535695, 0.89404470,
1.00000000, 0.95201559, 0.90658983,
1.00000000, 0.95851906, 0.91894041,
1.00000000, 0.96487079, 0.93109690,
1.00000000, 0.97107439, 0.94305985,
1.00000000, 0.97713351, 0.95482993,
1.00000000, 0.98305189, 0.96640795,
1.00000000, 0.98883326, 0.97779486,
1.00000000, 0.99448139, 0.98899179,
1.00000000, 1.00000000, 1.00000000,
0.98947904, 0.99348723, 1.00000000,
0.97940448, 0.98722715, 1.00000000,
0.96975025, 0.98120637, 1.00000000,
0.96049223, 0.97541240, 1.00000000,
0.95160805, 0.96983355, 1.00000000,
0.94303638, 0.96443333, 1.00000000,
0.93480451, 0.95923080, 1.00000000,
0.92689056, 0.95421394, 1.00000000,
0.91927697, 0.94937330, 1.00000000,
0.91194747, 0.94470005, 1.00000000,
0.90488690, 0.94018594, 1.00000000,
0.89808115, 0.93582323, 1.00000000,
0.89151710, 0.93160469, 1.00000000,
0.88518247, 0.92752354, 1.00000000,
0.87906581, 0.92357340, 1.00000000,
0.87315640, 0.91974827, 1.00000000,
0.86744421, 0.91604254, 1.00000000,
0.86191983, 0.91245088, 1.00000000,
0.85657444, 0.90896831, 1.00000000,
0.85139976, 0.90559011, 1.00000000,
0.84638799, 0.90231183, 1.00000000,
0.84153180, 0.89912926, 1.00000000,
0.83682430, 0.89603843, 1.00000000,
0.83225897, 0.89303558, 1.00000000,
0.82782969, 0.89011714, 1.00000000,
0.82353066, 0.88727974, 1.00000000,
0.81935641, 0.88452017, 1.00000000,
0.81530175, 0.88183541, 1.00000000,
0.81136180, 0.87922257, 1.00000000,
0.80753191, 0.87667891, 1.00000000,
0.80380769, 0.87420182, 1.00000000,
0.80018497, 0.87178882, 1.00000000,
0.79665980, 0.86943756, 1.00000000,
0.79322843, 0.86714579, 1.00000000,
0.78988728, 0.86491137, 1.00000000,
0.78663296, 0.86273225, 1.00000000,
0.78346225, 0.86060650, 1.00000000,
0.78037207, 0.85853224, 1.00000000,
0.77735950, 0.85650771, 1.00000000,
0.77442176, 0.85453121, 1.00000000,
0.77155617, 0.85260112, 1.00000000,
0.76876022, 0.85071588, 1.00000000,
0.76603147, 0.84887402, 1.00000000,
0.76336762, 0.84707411, 1.00000000,
0.76076645, 0.84531479, 1.00000000,
0.75822586, 0.84359476, 1.00000000,
0.75574383, 0.84191277, 1.00000000,
0.75331843, 0.84026762, 1.00000000,
0.75094780, 0.83865816, 1.00000000,
0.74863017, 0.83708329, 1.00000000,
0.74636386, 0.83554194, 1.00000000,
0.74414722, 0.83403311, 1.00000000,
0.74197871, 0.83255582, 1.00000000,
0.73985682, 0.83110912, 1.00000000,
0.73778012, 0.82969211, 1.00000000,
0.73574723, 0.82830393, 1.00000000,
0.73375683, 0.82694373, 1.00000000,
0.73180765, 0.82561071, 1.00000000,
0.72989845, 0.82430410, 1.00000000,
0.72802807, 0.82302316, 1.00000000,
0.72619537, 0.82176715, 1.00000000,
0.72439927, 0.82053539, 1.00000000,
0.72263872, 0.81932722, 1.00000000,
0.72091270, 0.81814197, 1.00000000,
0.71922025, 0.81697905, 1.00000000,
0.71756043, 0.81583783, 1.00000000,
0.71593234, 0.81471775, 1.00000000,
0.71433510, 0.81361825, 1.00000000,
0.71276788, 0.81253878, 1.00000000,
0.71122987, 0.81147883, 1.00000000,
0.70972029, 0.81043789, 1.00000000,
0.70823838, 0.80941546, 1.00000000,
0.70678342, 0.80841109, 1.00000000,
0.70535469, 0.80742432, 1.00000000,
0.70395153, 0.80645469, 1.00000000,
0.70257327, 0.80550180, 1.00000000,
0.70121928, 0.80456522, 1.00000000,
0.69988894, 0.80364455, 1.00000000,
0.69858167, 0.80273941, 1.00000000,
0.69729688, 0.80184943, 1.00000000,
0.69603402, 0.80097423, 1.00000000,
0.69479255, 0.80011347, 1.00000000,
0.69357196, 0.79926681, 1.00000000,
0.69237173, 0.79843391, 1.00000000,
0.69119138, 0.79761446, 1.00000000,
0.69003044, 0.79680814, 1.00000000,
0.68888844, 0.79601466, 1.00000000,
0.68776494, 0.79523371, 1.00000000,
0.68665951, 0.79446502, 1.00000000,
0.68557173, 0.79370830, 1.00000000,
0.68450119, 0.79296330, 1.00000000,
0.68344751, 0.79222975, 1.00000000,
0.68241029, 0.79150740, 1.00000000,
0.68138918, 0.79079600, 1.00000000,
0.68038380, 0.79009531, 1.00000000,
0.67939381, 0.78940511, 1.00000000,
0.67841888, 0.78872517, 1.00000000,
0.67745866, 0.78805526, 1.00000000,
0.67651284, 0.78739518, 1.00000000,
0.67558112, 0.78674472, 1.00000000,
0.67466317, 0.78610368, 1.00000000,
0.67375872, 0.78547186, 1.00000000,
0.67286748, 0.78484907, 1.00000000,
0.67198916, 0.78423512, 1.00000000,
0.67112350, 0.78362984, 1.00000000,
0.67027024, 0.78303305, 1.00000000,
0.66942911, 0.78244457, 1.00000000,
0.66859988, 0.78186425, 1.00000000,
0.66778228, 0.78129191, 1.00000000,
0.66697610, 0.78072740, 1.00000000,
0.66618110, 0.78017057, 1.00000000,
0.66539706, 0.77962127, 1.00000000,
0.66462376, 0.77907934, 1.00000000,
0.66386098, 0.77854465, 1.00000000,
0.66310852, 0.77801705, 1.00000000,
0.66236618, 0.77749642, 1.00000000,
0.66163375, 0.77698261, 1.00000000,
0.66091106, 0.77647551, 1.00000000,
0.66019791, 0.77597498, 1.00000000,
0.65949412, 0.77548090, 1.00000000,
0.65879952, 0.77499315, 1.00000000,
0.65811392, 0.77451161, 1.00000000,
0.65743716, 0.77403618, 1.00000000,
0.65676908, 0.77356673, 1.00000000,
0.65610952, 0.77310316, 1.00000000,
0.65545831, 0.77264537, 1.00000000,
0.65481530, 0.77219324, 1.00000000,
0.65418036, 0.77174669, 1.00000000,
0.65355332, 0.77130560, 1.00000000,
0.65293404, 0.77086988, 1.00000000,
0.65232240, 0.77043944, 1.00000000,
0.65171824, 0.77001419, 1.00000000,
0.65112144, 0.76959404, 1.00000000,
0.65053187, 0.76917889, 1.00000000,
0.64994941, 0.76876866, 1.00000000,
0.64937392, 0.76836326, 1.00000000
};
}