commit f9c69a2c37f7e7369282a092bd73ee9d0fc6bc48
author Michael Wright <michaelwr@google.com> Tue Mar 30 18:21:08 2021 +0000
committer Gerrit Code Review <noreply-gerritcodereview@google.com> Tue Mar 30 18:21:08 2021 +0000
tree 5aad1bf55239f929b7c639ed53ea3a5b10237ac6
parent ba4eeb87ddb9da0ddf21e803a984ceab4b5f557c
parent 2aaa220e0f1e6343abe4c160313d85e02aba1689

Merge "[Improvement]Fix loss of permissibleRatio calcaulation accuracy."

services/core/java/com/android/server/display/BrightnessMappingStrategy.java

diff --git a/services/core/java/com/android/server/display/BrightnessMappingStrategy.java b/services/core/java/com/android/server/display/BrightnessMappingStrategy.java
index 6f12155..6a407e9 100644
--- a/services/core/java/com/android/server/display/BrightnessMappingStrategy.java
+++ b/services/core/java/com/android/server/display/BrightnessMappingStrategy.java
@@ -440,9 +440,8 @@
     }
 
     private float permissibleRatio(float currLux, float prevLux) {
-        return MathUtils.exp(MAX_GRAD
-                * (MathUtils.log(currLux + LUX_GRAD_SMOOTHING)
-                    - MathUtils.log(prevLux + LUX_GRAD_SMOOTHING)));
+        return MathUtils.pow((currLux + LUX_GRAD_SMOOTHING)
+                / (prevLux + LUX_GRAD_SMOOTHING), MAX_GRAD);
     }
 
     protected float inferAutoBrightnessAdjustment(float maxGamma, float desiredBrightness,