| /* |
| * 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 com.android.server.display; |
| |
| import android.annotation.Nullable; |
| import android.content.pm.ApplicationInfo; |
| import android.content.res.Resources; |
| import android.content.res.TypedArray; |
| import android.hardware.display.BrightnessConfiguration; |
| import android.hardware.display.BrightnessCorrection; |
| import android.os.PowerManager; |
| import android.util.MathUtils; |
| import android.util.Pair; |
| import android.util.Slog; |
| import android.util.Spline; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.util.Preconditions; |
| import com.android.server.display.utils.Plog; |
| |
| import java.io.PrintWriter; |
| import java.util.Arrays; |
| |
| /** |
| * A utility to map from an ambient brightness to a display's "backlight" brightness based on the |
| * available display information and brightness configuration. |
| * |
| * Note that without a mapping from the nits to a display backlight level, any |
| * {@link BrightnessConfiguration}s that are set are just ignored. |
| */ |
| public abstract class BrightnessMappingStrategy { |
| private static final String TAG = "BrightnessMappingStrategy"; |
| |
| private static final float LUX_GRAD_SMOOTHING = 0.25f; |
| private static final float MAX_GRAD = 1.0f; |
| |
| protected boolean mLoggingEnabled; |
| |
| private static final Plog PLOG = Plog.createSystemPlog(TAG); |
| |
| @Nullable |
| public static BrightnessMappingStrategy create(Resources resources) { |
| float[] luxLevels = getLuxLevels(resources.getIntArray( |
| com.android.internal.R.array.config_autoBrightnessLevels)); |
| int[] brightnessLevelsBacklight = resources.getIntArray( |
| com.android.internal.R.array.config_autoBrightnessLcdBacklightValues); |
| float[] brightnessLevelsNits = getFloatArray(resources.obtainTypedArray( |
| com.android.internal.R.array.config_autoBrightnessDisplayValuesNits)); |
| float autoBrightnessAdjustmentMaxGamma = resources.getFraction( |
| com.android.internal.R.fraction.config_autoBrightnessAdjustmentMaxGamma, |
| 1, 1); |
| |
| float[] nitsRange = getFloatArray(resources.obtainTypedArray( |
| com.android.internal.R.array.config_screenBrightnessNits)); |
| int[] backlightRange = resources.getIntArray( |
| com.android.internal.R.array.config_screenBrightnessBacklight); |
| |
| if (isValidMapping(nitsRange, backlightRange) |
| && isValidMapping(luxLevels, brightnessLevelsNits)) { |
| int minimumBacklight = resources.getInteger( |
| com.android.internal.R.integer.config_screenBrightnessSettingMinimum); |
| int maximumBacklight = resources.getInteger( |
| com.android.internal.R.integer.config_screenBrightnessSettingMaximum); |
| if (backlightRange[0] > minimumBacklight |
| || backlightRange[backlightRange.length - 1] < maximumBacklight) { |
| Slog.w(TAG, "Screen brightness mapping does not cover whole range of available " + |
| "backlight values, autobrightness functionality may be impaired."); |
| } |
| BrightnessConfiguration.Builder builder = new BrightnessConfiguration.Builder( |
| luxLevels, brightnessLevelsNits); |
| return new PhysicalMappingStrategy(builder.build(), nitsRange, backlightRange, |
| autoBrightnessAdjustmentMaxGamma); |
| } else if (isValidMapping(luxLevels, brightnessLevelsBacklight)) { |
| return new SimpleMappingStrategy(luxLevels, brightnessLevelsBacklight, |
| autoBrightnessAdjustmentMaxGamma); |
| } else { |
| return null; |
| } |
| } |
| |
| private static float[] getLuxLevels(int[] lux) { |
| // The first control point is implicit and always at 0 lux. |
| float[] levels = new float[lux.length + 1]; |
| for (int i = 0; i < lux.length; i++) { |
| levels[i + 1] = (float) lux[i]; |
| } |
| return levels; |
| } |
| |
| private static float[] getFloatArray(TypedArray array) { |
| final int N = array.length(); |
| float[] vals = new float[N]; |
| for (int i = 0; i < N; i++) { |
| vals[i] = array.getFloat(i, -1.0f); |
| } |
| array.recycle(); |
| return vals; |
| } |
| |
| private static boolean isValidMapping(float[] x, float[] y) { |
| if (x == null || y == null || x.length == 0 || y.length == 0) { |
| return false; |
| } |
| if (x.length != y.length) { |
| return false; |
| } |
| final int N = x.length; |
| float prevX = x[0]; |
| float prevY = y[0]; |
| if (prevX < 0 || prevY < 0 || Float.isNaN(prevX) || Float.isNaN(prevY)) { |
| return false; |
| } |
| for (int i = 1; i < N; i++) { |
| if (prevX >= x[i] || prevY > y[i]) { |
| return false; |
| } |
| if (Float.isNaN(x[i]) || Float.isNaN(y[i])) { |
| return false; |
| } |
| prevX = x[i]; |
| prevY = y[i]; |
| } |
| return true; |
| } |
| |
| private static boolean isValidMapping(float[] x, int[] y) { |
| if (x == null || y == null || x.length == 0 || y.length == 0) { |
| return false; |
| } |
| if (x.length != y.length) { |
| return false; |
| } |
| final int N = x.length; |
| float prevX = x[0]; |
| int prevY = y[0]; |
| if (prevX < 0 || prevY < 0 || Float.isNaN(prevX)) { |
| return false; |
| } |
| for (int i = 1; i < N; i++) { |
| if (prevX >= x[i] || prevY > y[i]) { |
| return false; |
| } |
| if (Float.isNaN(x[i])) { |
| return false; |
| } |
| prevX = x[i]; |
| prevY = y[i]; |
| } |
| return true; |
| } |
| |
| /** |
| * Enable/disable logging. |
| * |
| * @param loggingEnabled |
| * Whether logging should be on/off. |
| * |
| * @return Whether the method succeeded or not. |
| */ |
| public boolean setLoggingEnabled(boolean loggingEnabled) { |
| if (mLoggingEnabled == loggingEnabled) { |
| return false; |
| } |
| mLoggingEnabled = loggingEnabled; |
| return true; |
| } |
| |
| /** |
| * Sets the {@link BrightnessConfiguration}. |
| * |
| * @param config The new configuration. If {@code null} is passed, the default configuration is |
| * used. |
| * @return Whether the brightness configuration has changed. |
| */ |
| public abstract boolean setBrightnessConfiguration(@Nullable BrightnessConfiguration config); |
| |
| /** |
| * Returns the desired brightness of the display based on the current ambient lux, including |
| * any context-related corrections. |
| * |
| * The returned brightness will be in the range [0, 1.0], where 1.0 is the display at max |
| * brightness and 0 is the display at minimum brightness. |
| * |
| * @param lux The current ambient brightness in lux. |
| * @param packageName the foreground app package name. |
| * @param category the foreground app package category. |
| * @return The desired brightness of the display normalized to the range [0, 1.0]. |
| */ |
| public abstract float getBrightness(float lux, String packageName, |
| @ApplicationInfo.Category int category); |
| |
| /** |
| * Returns the desired brightness of the display based on the current ambient lux. |
| * |
| * The returned brightness wil be in the range [0, 1.0], where 1.0 is the display at max |
| * brightness and 0 is the display at minimum brightness. |
| * |
| * @param lux The current ambient brightness in lux. |
| * |
| * @return The desired brightness of the display normalized to the range [0, 1.0]. |
| */ |
| public float getBrightness(float lux) { |
| return getBrightness(lux, null /* packageName */, ApplicationInfo.CATEGORY_UNDEFINED); |
| } |
| |
| /** |
| * Returns the current auto-brightness adjustment. |
| * |
| * The returned adjustment is a value in the range [-1.0, 1.0] such that |
| * {@code config_autoBrightnessAdjustmentMaxGamma<sup>-adjustment</sup>} is used to gamma |
| * correct the brightness curve. |
| */ |
| public abstract float getAutoBrightnessAdjustment(); |
| |
| /** |
| * Sets the auto-brightness adjustment. |
| * |
| * @param adjustment The desired auto-brightness adjustment. |
| * @return Whether the auto-brightness adjustment has changed. |
| * |
| * @Deprecated The auto-brightness adjustment should not be set directly, but rather inferred |
| * from user data points. |
| */ |
| public abstract boolean setAutoBrightnessAdjustment(float adjustment); |
| |
| /** |
| * Converts the provided backlight value to nits if possible. |
| * |
| * Returns -1.0f if there's no available mapping for the backlight to nits. |
| */ |
| public abstract float convertToNits(int backlight); |
| |
| /** |
| * Adds a user interaction data point to the brightness mapping. |
| * |
| * This data point <b>must</b> exist on the brightness curve as a result of this call. This is |
| * so that the next time we come to query what the screen brightness should be, we get what the |
| * user requested rather than immediately changing to some other value. |
| * |
| * Currently, we only keep track of one of these at a time to constrain what can happen to the |
| * curve. |
| */ |
| public abstract void addUserDataPoint(float lux, float brightness); |
| |
| /** |
| * Removes any short term adjustments made to the curve from user interactions. |
| * |
| * Note that this does *not* reset the mapping to its initial state, any brightness |
| * configurations that have been applied will continue to be in effect. This solely removes the |
| * effects of user interactions on the model. |
| */ |
| public abstract void clearUserDataPoints(); |
| |
| /** @return True if there are any short term adjustments applied to the curve. */ |
| public abstract boolean hasUserDataPoints(); |
| |
| /** @return True if the current brightness configuration is the default one. */ |
| public abstract boolean isDefaultConfig(); |
| |
| /** @return The default brightness configuration. */ |
| public abstract BrightnessConfiguration getDefaultConfig(); |
| |
| public abstract void dump(PrintWriter pw); |
| |
| protected float normalizeAbsoluteBrightness(int brightness) { |
| brightness = MathUtils.constrain(brightness, |
| PowerManager.BRIGHTNESS_OFF, PowerManager.BRIGHTNESS_ON); |
| return (float) brightness / PowerManager.BRIGHTNESS_ON; |
| } |
| |
| private Pair<float[], float[]> insertControlPoint( |
| float[] luxLevels, float[] brightnessLevels, float lux, float brightness) { |
| final int idx = findInsertionPoint(luxLevels, lux); |
| final float[] newLuxLevels; |
| final float[] newBrightnessLevels; |
| if (idx == luxLevels.length) { |
| newLuxLevels = Arrays.copyOf(luxLevels, luxLevels.length + 1); |
| newBrightnessLevels = Arrays.copyOf(brightnessLevels, brightnessLevels.length + 1); |
| newLuxLevels[idx] = lux; |
| newBrightnessLevels[idx] = brightness; |
| } else if (luxLevels[idx] == lux) { |
| newLuxLevels = Arrays.copyOf(luxLevels, luxLevels.length); |
| newBrightnessLevels = Arrays.copyOf(brightnessLevels, brightnessLevels.length); |
| newBrightnessLevels[idx] = brightness; |
| } else { |
| newLuxLevels = Arrays.copyOf(luxLevels, luxLevels.length + 1); |
| System.arraycopy(newLuxLevels, idx, newLuxLevels, idx+1, luxLevels.length - idx); |
| newLuxLevels[idx] = lux; |
| newBrightnessLevels = Arrays.copyOf(brightnessLevels, brightnessLevels.length + 1); |
| System.arraycopy(newBrightnessLevels, idx, newBrightnessLevels, idx+1, |
| brightnessLevels.length - idx); |
| newBrightnessLevels[idx] = brightness; |
| } |
| smoothCurve(newLuxLevels, newBrightnessLevels, idx); |
| return Pair.create(newLuxLevels, newBrightnessLevels); |
| } |
| |
| /** |
| * Returns the index of the first value that's less than or equal to {@code val}. |
| * |
| * This assumes that {@code arr} is sorted. If all values in {@code arr} are greater |
| * than val, then it will return the length of arr as the insertion point. |
| */ |
| private int findInsertionPoint(float[] arr, float val) { |
| for (int i = 0; i < arr.length; i++) { |
| if (val <= arr[i]) { |
| return i; |
| } |
| } |
| return arr.length; |
| } |
| |
| private void smoothCurve(float[] lux, float[] brightness, int idx) { |
| if (mLoggingEnabled) { |
| PLOG.logCurve("unsmoothed curve", lux, brightness); |
| } |
| float prevLux = lux[idx]; |
| float prevBrightness = brightness[idx]; |
| // Smooth curve for data points above the newly introduced point |
| for (int i = idx+1; i < lux.length; i++) { |
| float currLux = lux[i]; |
| float currBrightness = brightness[i]; |
| float maxBrightness = prevBrightness * permissibleRatio(currLux, prevLux); |
| float newBrightness = MathUtils.constrain( |
| currBrightness, prevBrightness, maxBrightness); |
| if (newBrightness == currBrightness) { |
| break; |
| } |
| prevLux = currLux; |
| prevBrightness = newBrightness; |
| brightness[i] = newBrightness; |
| } |
| // Smooth curve for data points below the newly introduced point |
| prevLux = lux[idx]; |
| prevBrightness = brightness[idx]; |
| for (int i = idx-1; i >= 0; i--) { |
| float currLux = lux[i]; |
| float currBrightness = brightness[i]; |
| float minBrightness = prevBrightness * permissibleRatio(currLux, prevLux); |
| float newBrightness = MathUtils.constrain( |
| currBrightness, minBrightness, prevBrightness); |
| if (newBrightness == currBrightness) { |
| break; |
| } |
| prevLux = currLux; |
| prevBrightness = newBrightness; |
| brightness[i] = newBrightness; |
| } |
| if (mLoggingEnabled) { |
| PLOG.logCurve("smoothed curve", lux, brightness); |
| } |
| } |
| |
| private float permissibleRatio(float currLux, float prevLux) { |
| return MathUtils.exp(MAX_GRAD |
| * (MathUtils.log(currLux + LUX_GRAD_SMOOTHING) |
| - MathUtils.log(prevLux + LUX_GRAD_SMOOTHING))); |
| } |
| |
| protected float inferAutoBrightnessAdjustment(float maxGamma, float desiredBrightness, |
| float currentBrightness) { |
| float adjustment = 0; |
| float gamma = Float.NaN; |
| // Extreme edge cases: use a simpler heuristic, as proper gamma correction around the edges |
| // affects the curve rather drastically. |
| if (currentBrightness <= 0.1f || currentBrightness >= 0.9f) { |
| adjustment = (desiredBrightness - currentBrightness); |
| // Edge case: darkest adjustment possible. |
| } else if (desiredBrightness == 0) { |
| adjustment = -1; |
| // Edge case: brightest adjustment possible. |
| } else if (desiredBrightness == 1) { |
| adjustment = +1; |
| } else { |
| // current^gamma = desired => gamma = log[current](desired) |
| gamma = MathUtils.log(desiredBrightness) / MathUtils.log(currentBrightness); |
| // max^-adjustment = gamma => adjustment = -log[max](gamma) |
| adjustment = -MathUtils.log(gamma) / MathUtils.log(maxGamma); |
| } |
| adjustment = MathUtils.constrain(adjustment, -1, +1); |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "inferAutoBrightnessAdjustment: " + maxGamma + "^" + -adjustment + "=" + |
| MathUtils.pow(maxGamma, -adjustment) + " == " + gamma); |
| Slog.d(TAG, "inferAutoBrightnessAdjustment: " + currentBrightness + "^" + gamma + "=" + |
| MathUtils.pow(currentBrightness, gamma) + " == " + desiredBrightness); |
| } |
| return adjustment; |
| } |
| |
| protected Pair<float[], float[]> getAdjustedCurve(float[] lux, float[] brightness, |
| float userLux, float userBrightness, float adjustment, float maxGamma) { |
| float[] newLux = lux; |
| float[] newBrightness = Arrays.copyOf(brightness, brightness.length); |
| if (mLoggingEnabled) { |
| PLOG.logCurve("unadjusted curve", newLux, newBrightness); |
| } |
| adjustment = MathUtils.constrain(adjustment, -1, 1); |
| float gamma = MathUtils.pow(maxGamma, -adjustment); |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "getAdjustedCurve: " + maxGamma + "^" + -adjustment + "=" + |
| MathUtils.pow(maxGamma, -adjustment) + " == " + gamma); |
| } |
| if (gamma != 1) { |
| for (int i = 0; i < newBrightness.length; i++) { |
| newBrightness[i] = MathUtils.pow(newBrightness[i], gamma); |
| } |
| } |
| if (mLoggingEnabled) { |
| PLOG.logCurve("gamma adjusted curve", newLux, newBrightness); |
| } |
| if (userLux != -1) { |
| Pair<float[], float[]> curve = insertControlPoint(newLux, newBrightness, userLux, |
| userBrightness); |
| newLux = curve.first; |
| newBrightness = curve.second; |
| if (mLoggingEnabled) { |
| PLOG.logCurve("gamma and user adjusted curve", newLux, newBrightness); |
| // This is done for comparison. |
| curve = insertControlPoint(lux, brightness, userLux, userBrightness); |
| PLOG.logCurve("user adjusted curve", curve.first ,curve.second); |
| } |
| } |
| return Pair.create(newLux, newBrightness); |
| } |
| |
| /** |
| * A {@link BrightnessMappingStrategy} that maps from ambient room brightness directly to the |
| * backlight of the display. |
| * |
| * Since we don't have information about the display's physical brightness, any brightness |
| * configurations that are set are just ignored. |
| */ |
| private static class SimpleMappingStrategy extends BrightnessMappingStrategy { |
| // Lux control points |
| private final float[] mLux; |
| // Brightness control points normalized to [0, 1] |
| private final float[] mBrightness; |
| |
| private Spline mSpline; |
| private float mMaxGamma; |
| private float mAutoBrightnessAdjustment; |
| private float mUserLux; |
| private float mUserBrightness; |
| |
| public SimpleMappingStrategy(float[] lux, int[] brightness, float maxGamma) { |
| Preconditions.checkArgument(lux.length != 0 && brightness.length != 0, |
| "Lux and brightness arrays must not be empty!"); |
| Preconditions.checkArgument(lux.length == brightness.length, |
| "Lux and brightness arrays must be the same length!"); |
| Preconditions.checkArrayElementsInRange(lux, 0, Float.MAX_VALUE, "lux"); |
| Preconditions.checkArrayElementsInRange(brightness, |
| 0, Integer.MAX_VALUE, "brightness"); |
| |
| final int N = brightness.length; |
| mLux = new float[N]; |
| mBrightness = new float[N]; |
| for (int i = 0; i < N; i++) { |
| mLux[i] = lux[i]; |
| mBrightness[i] = normalizeAbsoluteBrightness(brightness[i]); |
| } |
| |
| mMaxGamma = maxGamma; |
| mAutoBrightnessAdjustment = 0; |
| mUserLux = -1; |
| mUserBrightness = -1; |
| if (mLoggingEnabled) { |
| PLOG.start("simple mapping strategy"); |
| } |
| computeSpline(); |
| } |
| |
| @Override |
| public boolean setBrightnessConfiguration(@Nullable BrightnessConfiguration config) { |
| return false; |
| } |
| |
| @Override |
| public float getBrightness(float lux, String packageName, |
| @ApplicationInfo.Category int category) { |
| return mSpline.interpolate(lux); |
| } |
| |
| @Override |
| public float getAutoBrightnessAdjustment() { |
| return mAutoBrightnessAdjustment; |
| } |
| |
| @Override |
| public boolean setAutoBrightnessAdjustment(float adjustment) { |
| adjustment = MathUtils.constrain(adjustment, -1, 1); |
| if (adjustment == mAutoBrightnessAdjustment) { |
| return false; |
| } |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "setAutoBrightnessAdjustment: " + mAutoBrightnessAdjustment + " => " + |
| adjustment); |
| PLOG.start("auto-brightness adjustment"); |
| } |
| mAutoBrightnessAdjustment = adjustment; |
| computeSpline(); |
| return true; |
| } |
| |
| @Override |
| public float convertToNits(int backlight) { |
| return -1.0f; |
| } |
| |
| @Override |
| public void addUserDataPoint(float lux, float brightness) { |
| float unadjustedBrightness = getUnadjustedBrightness(lux); |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "addUserDataPoint: (" + lux + "," + brightness + ")"); |
| PLOG.start("add user data point") |
| .logPoint("user data point", lux, brightness) |
| .logPoint("current brightness", lux, unadjustedBrightness); |
| } |
| float adjustment = inferAutoBrightnessAdjustment(mMaxGamma, |
| brightness /* desiredBrightness */, |
| unadjustedBrightness /* currentBrightness */); |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "addUserDataPoint: " + mAutoBrightnessAdjustment + " => " + |
| adjustment); |
| } |
| mAutoBrightnessAdjustment = adjustment; |
| mUserLux = lux; |
| mUserBrightness = brightness; |
| computeSpline(); |
| } |
| |
| @Override |
| public void clearUserDataPoints() { |
| if (mUserLux != -1) { |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "clearUserDataPoints: " + mAutoBrightnessAdjustment + " => 0"); |
| PLOG.start("clear user data points") |
| .logPoint("user data point", mUserLux, mUserBrightness); |
| } |
| mAutoBrightnessAdjustment = 0; |
| mUserLux = -1; |
| mUserBrightness = -1; |
| computeSpline(); |
| } |
| } |
| |
| @Override |
| public boolean hasUserDataPoints() { |
| return mUserLux != -1; |
| } |
| |
| @Override |
| public boolean isDefaultConfig() { |
| return true; |
| } |
| |
| @Override |
| public BrightnessConfiguration getDefaultConfig() { |
| return null; |
| } |
| |
| @Override |
| public void dump(PrintWriter pw) { |
| pw.println("SimpleMappingStrategy"); |
| pw.println(" mSpline=" + mSpline); |
| pw.println(" mMaxGamma=" + mMaxGamma); |
| pw.println(" mAutoBrightnessAdjustment=" + mAutoBrightnessAdjustment); |
| pw.println(" mUserLux=" + mUserLux); |
| pw.println(" mUserBrightness=" + mUserBrightness); |
| } |
| |
| private void computeSpline() { |
| Pair<float[], float[]> curve = getAdjustedCurve(mLux, mBrightness, mUserLux, |
| mUserBrightness, mAutoBrightnessAdjustment, mMaxGamma); |
| mSpline = Spline.createSpline(curve.first, curve.second); |
| } |
| |
| private float getUnadjustedBrightness(float lux) { |
| Spline spline = Spline.createSpline(mLux, mBrightness); |
| return spline.interpolate(lux); |
| } |
| } |
| |
| /** A {@link BrightnessMappingStrategy} that maps from ambient room brightness to the physical |
| * range of the display, rather than to the range of the backlight control (typically 0-255). |
| * |
| * By mapping through the physical brightness, the curve becomes portable across devices and |
| * gives us more resolution in the resulting mapping. |
| */ |
| @VisibleForTesting |
| static class PhysicalMappingStrategy extends BrightnessMappingStrategy { |
| // The current brightness configuration. |
| private BrightnessConfiguration mConfig; |
| |
| // A spline mapping from the current ambient light in lux to the desired display brightness |
| // in nits. |
| private Spline mBrightnessSpline; |
| |
| // A spline mapping from nits to the corresponding backlight value, normalized to the range |
| // [0, 1.0]. |
| private final Spline mNitsToBacklightSpline; |
| |
| // The default brightness configuration. |
| private final BrightnessConfiguration mDefaultConfig; |
| |
| // A spline mapping from the device's backlight value, normalized to the range [0, 1.0], to |
| // a brightness in nits. |
| private Spline mBacklightToNitsSpline; |
| |
| private float mMaxGamma; |
| private float mAutoBrightnessAdjustment; |
| private float mUserLux; |
| private float mUserBrightness; |
| |
| public PhysicalMappingStrategy(BrightnessConfiguration config, float[] nits, |
| int[] backlight, float maxGamma) { |
| Preconditions.checkArgument(nits.length != 0 && backlight.length != 0, |
| "Nits and backlight arrays must not be empty!"); |
| Preconditions.checkArgument(nits.length == backlight.length, |
| "Nits and backlight arrays must be the same length!"); |
| Preconditions.checkNotNull(config); |
| Preconditions.checkArrayElementsInRange(nits, 0, Float.MAX_VALUE, "nits"); |
| Preconditions.checkArrayElementsInRange(backlight, |
| PowerManager.BRIGHTNESS_OFF, PowerManager.BRIGHTNESS_ON, "backlight"); |
| |
| mMaxGamma = maxGamma; |
| mAutoBrightnessAdjustment = 0; |
| mUserLux = -1; |
| mUserBrightness = -1; |
| |
| // Setup the backlight spline |
| final int N = nits.length; |
| float[] normalizedBacklight = new float[N]; |
| for (int i = 0; i < N; i++) { |
| normalizedBacklight[i] = normalizeAbsoluteBrightness(backlight[i]); |
| } |
| |
| mNitsToBacklightSpline = Spline.createSpline(nits, normalizedBacklight); |
| mBacklightToNitsSpline = Spline.createSpline(normalizedBacklight, nits); |
| |
| mDefaultConfig = config; |
| if (mLoggingEnabled) { |
| PLOG.start("physical mapping strategy"); |
| } |
| mConfig = config; |
| computeSpline(); |
| } |
| |
| @Override |
| public boolean setBrightnessConfiguration(@Nullable BrightnessConfiguration config) { |
| if (config == null) { |
| config = mDefaultConfig; |
| } |
| if (config.equals(mConfig)) { |
| return false; |
| } |
| if (mLoggingEnabled) { |
| PLOG.start("brightness configuration"); |
| } |
| mConfig = config; |
| computeSpline(); |
| return true; |
| } |
| |
| @Override |
| public float getBrightness(float lux, String packageName, |
| @ApplicationInfo.Category int category) { |
| float nits = mBrightnessSpline.interpolate(lux); |
| float backlight = mNitsToBacklightSpline.interpolate(nits); |
| // Correct the brightness according to the current application and its category, but |
| // only if no user data point is set (as this will oevrride the user setting). |
| if (mUserLux == -1) { |
| backlight = correctBrightness(backlight, packageName, category); |
| } else if (mLoggingEnabled) { |
| Slog.d(TAG, "user point set, correction not applied"); |
| } |
| return backlight; |
| } |
| |
| @Override |
| public float getAutoBrightnessAdjustment() { |
| return mAutoBrightnessAdjustment; |
| } |
| |
| @Override |
| public boolean setAutoBrightnessAdjustment(float adjustment) { |
| adjustment = MathUtils.constrain(adjustment, -1, 1); |
| if (adjustment == mAutoBrightnessAdjustment) { |
| return false; |
| } |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "setAutoBrightnessAdjustment: " + mAutoBrightnessAdjustment + " => " + |
| adjustment); |
| PLOG.start("auto-brightness adjustment"); |
| } |
| mAutoBrightnessAdjustment = adjustment; |
| computeSpline(); |
| return true; |
| } |
| |
| @Override |
| public float convertToNits(int backlight) { |
| return mBacklightToNitsSpline.interpolate(normalizeAbsoluteBrightness(backlight)); |
| } |
| |
| @Override |
| public void addUserDataPoint(float lux, float brightness) { |
| float unadjustedBrightness = getUnadjustedBrightness(lux); |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "addUserDataPoint: (" + lux + "," + brightness + ")"); |
| PLOG.start("add user data point") |
| .logPoint("user data point", lux, brightness) |
| .logPoint("current brightness", lux, unadjustedBrightness); |
| } |
| float adjustment = inferAutoBrightnessAdjustment(mMaxGamma, |
| brightness /* desiredBrightness */, |
| unadjustedBrightness /* currentBrightness */); |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "addUserDataPoint: " + mAutoBrightnessAdjustment + " => " + |
| adjustment); |
| } |
| mAutoBrightnessAdjustment = adjustment; |
| mUserLux = lux; |
| mUserBrightness = brightness; |
| computeSpline(); |
| } |
| |
| @Override |
| public void clearUserDataPoints() { |
| if (mUserLux != -1) { |
| if (mLoggingEnabled) { |
| Slog.d(TAG, "clearUserDataPoints: " + mAutoBrightnessAdjustment + " => 0"); |
| PLOG.start("clear user data points") |
| .logPoint("user data point", mUserLux, mUserBrightness); |
| } |
| mAutoBrightnessAdjustment = 0; |
| mUserLux = -1; |
| mUserBrightness = -1; |
| computeSpline(); |
| } |
| } |
| |
| @Override |
| public boolean hasUserDataPoints() { |
| return mUserLux != -1; |
| } |
| |
| @Override |
| public boolean isDefaultConfig() { |
| return mDefaultConfig.equals(mConfig); |
| } |
| |
| @Override |
| public BrightnessConfiguration getDefaultConfig() { |
| return mDefaultConfig; |
| } |
| |
| @Override |
| public void dump(PrintWriter pw) { |
| pw.println("PhysicalMappingStrategy"); |
| pw.println(" mConfig=" + mConfig); |
| pw.println(" mBrightnessSpline=" + mBrightnessSpline); |
| pw.println(" mNitsToBacklightSpline=" + mNitsToBacklightSpline); |
| pw.println(" mMaxGamma=" + mMaxGamma); |
| pw.println(" mAutoBrightnessAdjustment=" + mAutoBrightnessAdjustment); |
| pw.println(" mUserLux=" + mUserLux); |
| pw.println(" mUserBrightness=" + mUserBrightness); |
| } |
| |
| private void computeSpline() { |
| Pair<float[], float[]> defaultCurve = mConfig.getCurve(); |
| float[] defaultLux = defaultCurve.first; |
| float[] defaultNits = defaultCurve.second; |
| float[] defaultBacklight = new float[defaultNits.length]; |
| for (int i = 0; i < defaultBacklight.length; i++) { |
| defaultBacklight[i] = mNitsToBacklightSpline.interpolate(defaultNits[i]); |
| } |
| Pair<float[], float[]> curve = getAdjustedCurve(defaultLux, defaultBacklight, mUserLux, |
| mUserBrightness, mAutoBrightnessAdjustment, mMaxGamma); |
| float[] lux = curve.first; |
| float[] backlight = curve.second; |
| float[] nits = new float[backlight.length]; |
| for (int i = 0; i < nits.length; i++) { |
| nits[i] = mBacklightToNitsSpline.interpolate(backlight[i]); |
| } |
| mBrightnessSpline = Spline.createSpline(lux, nits); |
| } |
| |
| private float getUnadjustedBrightness(float lux) { |
| Pair<float[], float[]> curve = mConfig.getCurve(); |
| Spline spline = Spline.createSpline(curve.first, curve.second); |
| return mNitsToBacklightSpline.interpolate(spline.interpolate(lux)); |
| } |
| |
| private float correctBrightness(float brightness, String packageName, int category) { |
| if (packageName != null) { |
| BrightnessCorrection correction = mConfig.getCorrectionByPackageName(packageName); |
| if (correction != null) { |
| return correction.apply(brightness); |
| } |
| } |
| if (category != ApplicationInfo.CATEGORY_UNDEFINED) { |
| BrightnessCorrection correction = mConfig.getCorrectionByCategory(category); |
| if (correction != null) { |
| return correction.apply(brightness); |
| } |
| } |
| return brightness; |
| } |
| } |
| } |
