From 0bdb5dd0a94d0a01b98ee83b280eb16de19d1df1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sami=20Kalliom=C3=A4ki?= <sakal@webrtc.org>
Date: Wed, 28 Mar 2018 16:31:26 +0200
Subject: [PATCH] Fix framerate based bitrate adjuster.
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Fixes target bitrate calculation for framerate based adjuster. Adds new
API to bitrate adjuster - getCodecConfigFramerate() - that returns the
FPS that should be passed to MediaCodec on initialization.

Bug: b/73741487, cl/186656928
Change-Id: Ia4a5e99d302de67fbee0c132ab8e9392bc205b44
Reviewed-on: https://webrtc-review.googlesource.com/65162
Reviewed-by: Magnus Jedvert <magjed@webrtc.org>
Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22716}
---
 sdk/android/src/java/org/webrtc/BaseBitrateAdjuster.java | 2 +-
 sdk/android/src/java/org/webrtc/BitrateAdjuster.java     | 4 ++--
 .../src/java/org/webrtc/DynamicBitrateAdjuster.java      | 9 ++++++---
 .../src/java/org/webrtc/FramerateBitrateAdjuster.java    | 7 ++++++-
 .../src/java/org/webrtc/HardwareVideoEncoder.java        | 4 ++--
 5 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/sdk/android/src/java/org/webrtc/BaseBitrateAdjuster.java b/sdk/android/src/java/org/webrtc/BaseBitrateAdjuster.java
index ca9ebb52a8..19cf5ea38a 100644
--- a/sdk/android/src/java/org/webrtc/BaseBitrateAdjuster.java
+++ b/sdk/android/src/java/org/webrtc/BaseBitrateAdjuster.java
@@ -32,7 +32,7 @@ class BaseBitrateAdjuster implements BitrateAdjuster {
   }
 
   @Override
-  public int getAdjustedFramerate() {
+  public int getCodecConfigFramerate() {
     return targetFps;
   }
 }
diff --git a/sdk/android/src/java/org/webrtc/BitrateAdjuster.java b/sdk/android/src/java/org/webrtc/BitrateAdjuster.java
index 044a43a1eb..854ef067e5 100644
--- a/sdk/android/src/java/org/webrtc/BitrateAdjuster.java
+++ b/sdk/android/src/java/org/webrtc/BitrateAdjuster.java
@@ -26,6 +26,6 @@ interface BitrateAdjuster {
   /** Gets the current bitrate. */
   int getAdjustedBitrateBps();
 
-  /** Gets the current framerate. */
-  int getAdjustedFramerate();
+  /** Gets the framerate for initial codec configuration. */
+  int getCodecConfigFramerate();
 }
diff --git a/sdk/android/src/java/org/webrtc/DynamicBitrateAdjuster.java b/sdk/android/src/java/org/webrtc/DynamicBitrateAdjuster.java
index 742cfad7b6..1f970bbbbd 100644
--- a/sdk/android/src/java/org/webrtc/DynamicBitrateAdjuster.java
+++ b/sdk/android/src/java/org/webrtc/DynamicBitrateAdjuster.java
@@ -86,10 +86,13 @@ class DynamicBitrateAdjuster extends BaseBitrateAdjuster {
     timeSinceLastAdjustmentMs = 0;
   }
 
+  private double getBitrateAdjustmentScale() {
+    return Math.pow(BITRATE_ADJUSTMENT_MAX_SCALE,
+        (double) bitrateAdjustmentScaleExp / BITRATE_ADJUSTMENT_STEPS);
+  }
+
   @Override
   public int getAdjustedBitrateBps() {
-    return (int) (targetBitrateBps
-        * Math.pow(BITRATE_ADJUSTMENT_MAX_SCALE,
-              (double) bitrateAdjustmentScaleExp / BITRATE_ADJUSTMENT_STEPS));
+    return (int) (targetBitrateBps * getBitrateAdjustmentScale());
   }
 }
diff --git a/sdk/android/src/java/org/webrtc/FramerateBitrateAdjuster.java b/sdk/android/src/java/org/webrtc/FramerateBitrateAdjuster.java
index a0a0664bf6..b9d1af66c0 100644
--- a/sdk/android/src/java/org/webrtc/FramerateBitrateAdjuster.java
+++ b/sdk/android/src/java/org/webrtc/FramerateBitrateAdjuster.java
@@ -25,6 +25,11 @@ class FramerateBitrateAdjuster extends BaseBitrateAdjuster {
     }
     super.setTargets(targetBitrateBps, targetFps);
 
-    this.targetBitrateBps *= INITIAL_FPS / this.targetFps;
+    this.targetBitrateBps = this.targetBitrateBps * INITIAL_FPS / this.targetFps;
+  }
+
+  @Override
+  public int getCodecConfigFramerate() {
+    return INITIAL_FPS;
   }
 }
diff --git a/sdk/android/src/java/org/webrtc/HardwareVideoEncoder.java b/sdk/android/src/java/org/webrtc/HardwareVideoEncoder.java
index 7a05f37791..9b895cc993 100644
--- a/sdk/android/src/java/org/webrtc/HardwareVideoEncoder.java
+++ b/sdk/android/src/java/org/webrtc/HardwareVideoEncoder.java
@@ -17,7 +17,6 @@ import android.media.MediaCodecInfo;
 import android.media.MediaFormat;
 import android.opengl.GLES20;
 import android.os.Bundle;
-import javax.annotation.Nullable;
 import android.view.Surface;
 import java.io.IOException;
 import java.nio.ByteBuffer;
@@ -26,6 +25,7 @@ import java.util.Map;
 import java.util.concurrent.BlockingDeque;
 import java.util.concurrent.LinkedBlockingDeque;
 import java.util.concurrent.TimeUnit;
+import javax.annotation.Nullable;
 import org.webrtc.ThreadUtils.ThreadChecker;
 
 /** Android hardware video encoder. */
@@ -186,7 +186,7 @@ class HardwareVideoEncoder implements VideoEncoder {
       format.setInteger(MediaFormat.KEY_BIT_RATE, adjustedBitrate);
       format.setInteger(KEY_BITRATE_MODE, VIDEO_ControlRateConstant);
       format.setInteger(MediaFormat.KEY_COLOR_FORMAT, colorFormat);
-      format.setInteger(MediaFormat.KEY_FRAME_RATE, bitrateAdjuster.getAdjustedFramerate());
+      format.setInteger(MediaFormat.KEY_FRAME_RATE, bitrateAdjuster.getCodecConfigFramerate());
       format.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, keyFrameIntervalSec);
       if (codecType == VideoCodecType.H264) {
         String profileLevelId = params.get(VideoCodecInfo.H264_FMTP_PROFILE_LEVEL_ID);