From c007857ab9cc977a21d0099225e520388342c0d4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Per=20=C3=85hgren?= <peah@webrtc.org>
Date: Mon, 2 Oct 2017 14:47:38 +0200
Subject: [PATCH] AEC3 tunings to increase transparency
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This CL fine-tunes the internal AEC3 parameters to increase the
transparency of the nearend signal.

Bug: webrtc:8322
Change-Id: I2e35165082d88b8f2b1e8367d8ed0e29bd67b4e5
Reviewed-on: https://webrtc-review.googlesource.com/5365
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Commit-Queue: Per Åhgren <peah@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20082}
---
 .../audio_processing/aec3/suppression_gain.cc    |  2 +-
 .../audio_processing/include/audio_processing.h  | 16 ++++++++--------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/modules/audio_processing/aec3/suppression_gain.cc b/modules/audio_processing/aec3/suppression_gain.cc
index 83ae63c95e..9183e9181a 100644
--- a/modules/audio_processing/aec3/suppression_gain.cc
+++ b/modules/audio_processing/aec3/suppression_gain.cc
@@ -176,7 +176,7 @@ void GainToNoAudibleEcho(
     const std::array<float, kFftLengthBy2Plus1>& one_by_echo,
     std::array<float, kFftLengthBy2Plus1>* gain) {
   const float nearend_masking_margin =
-      low_noise_render ? 0.1f
+      low_noise_render ? 0.3f
                        : (saturated_echo ? config.param.gain_mask.m2
                                          : config.param.gain_mask.m3);
 
diff --git a/modules/audio_processing/include/audio_processing.h b/modules/audio_processing/include/audio_processing.h
index 6baa69118c..21d6018a6f 100644
--- a/modules/audio_processing/include/audio_processing.h
+++ b/modules/audio_processing/include/audio_processing.h
@@ -279,21 +279,21 @@ class AudioProcessing : public rtc::RefCountInterface {
         } erle;
 
         struct EpStrength {
-          float lf = 100.f;
-          float mf = 1000.f;
-          float hf = 5000.f;
+          float lf = 10.f;
+          float mf = 100.f;
+          float hf = 200.f;
           float default_len = 0.f;
         } ep_strength;
 
         struct Mask {
           float m1 = 0.01f;
           float m2 = 0.001f;
-          float m3 = 0.01f;
-          float m4 = 0.1f;
+          float m3 = 0.02f;  // Do not change.
+          float m4 = 0.3f;
         } gain_mask;
 
         struct EchoAudibility {
-          float low_render_limit = 192.f;
+          float low_render_limit = 4 * 64.f;
           float normal_render_limit = 64.f;
           float active_render_limit = 100.f;
         } echo_audibility;
@@ -313,8 +313,8 @@ class AudioProcessing : public rtc::RefCountInterface {
             float min_dec;
           };
 
-          GainChanges low_noise = {8.f, 8.f, 2.f, 2.f, 4.f, 4.f};
-          GainChanges normal = {4.f, 4.f, 2.f, 2.f, 1.2f, 2.f};
+          GainChanges low_noise = {8.f, 10.f, 2.f, 4.f, 4.f, 4.f};
+          GainChanges normal = {4.f, 10.f, 1.5f, 4.f, 2.f, 4.f};
           GainChanges saturation = {1.2f, 1.2f, 1.5f, 1.5f, 1.f, 1.f};
 
           float floor_first_increase = 0.001f;