commit 7fa4a729245a401209310400e7a4df4e416e96a2
author Alex Glaznev <glaznev@google.com> Tue Jan 17 23:32:02 2017
committer Alex Glaznev <glaznev@google.com> Tue Jan 17 23:32:02 2017
tree 3110223553bdc8dda445d2e60264381069f66c54
parent 6dbbd89f1876df167cbd4c6eb8b4ade488de1fc1

Increase bitrate adjustment values for VP8 Exynos encoder

For low bitrates actual encoder output bitrate may differ from target
by 3-4 times.
Also adjust adaptation speed based on bitrate variation from the target.

BUG=b/34233384
R=wzh@webrtc.org

Review-Url: https://codereview.webrtc.org/2640543003 .
Cr-Commit-Position: refs/heads/master@{#16128}

webrtc/sdk/android/api/org/webrtc/MediaCodecVideoEncoder.java

diff --git a/webrtc/sdk/android/api/org/webrtc/MediaCodecVideoEncoder.java b/webrtc/sdk/android/api/org/webrtc/MediaCodecVideoEncoder.java
index c3e2133..0c47c38 100644
--- a/webrtc/sdk/android/api/org/webrtc/MediaCodecVideoEncoder.java
+++ b/webrtc/sdk/android/api/org/webrtc/MediaCodecVideoEncoder.java
@@ -49,10 +49,10 @@
   private static final int BITRATE_ADJUSTMENT_FPS = 30;
   private static final int MAXIMUM_INITIAL_FPS = 30;
   private static final double BITRATE_CORRECTION_SEC = 3.0;
-  // Maximum bitrate correction scale - no more than 2 times.
-  private static final double BITRATE_CORRECTION_MAX_SCALE = 2;
+  // Maximum bitrate correction scale - no more than 4 times.
+  private static final double BITRATE_CORRECTION_MAX_SCALE = 4;
   // Amount of correction steps to reach correction maximum scale.
-  private static final int BITRATE_CORRECTION_STEPS = 10;
+  private static final int BITRATE_CORRECTION_STEPS = 20;
   // Forced key frame interval - used to reduce color distortions on Qualcomm platform.
   private static final long QCOM_VP8_KEY_FRAME_INTERVAL_ANDROID_M_MS = 25000;
   private static final long QCOM_VP8_KEY_FRAME_INTERVAL_ANDROID_N_MS = 15000;
@@ -753,12 +753,14 @@
       boolean bitrateAdjustmentScaleChanged = false;
       if (bitrateAccumulator > bitrateAccumulatorMax) {
         // Encoder generates too high bitrate - need to reduce the scale.
+        int bitrateAdjustmentInc = (int) (bitrateAccumulator / bitrateAccumulatorMax + 0.5);
+        bitrateAdjustmentScaleExp -= bitrateAdjustmentInc;
         bitrateAccumulator = bitrateAccumulatorMax;
-        bitrateAdjustmentScaleExp--;
         bitrateAdjustmentScaleChanged = true;
       } else if (bitrateAccumulator < -bitrateAccumulatorMax) {
         // Encoder generates too low bitrate - need to increase the scale.
-        bitrateAdjustmentScaleExp++;
+        int bitrateAdjustmentInc = (int) (-bitrateAccumulator / bitrateAccumulatorMax + 0.5);
+        bitrateAdjustmentScaleExp += bitrateAdjustmentInc;
         bitrateAccumulator = -bitrateAccumulatorMax;
         bitrateAdjustmentScaleChanged = true;
       }