From 8a15dd858a41b141a03e3c541affcc8d68441466 Mon Sep 17 00:00:00 2001
From: Bo-Rong Chen <borongchen@google.com>
Date: Thu, 11 Apr 2024 16:40:13 -0700
Subject: [PATCH] [media] Revise OpusAudioDecoder::Reset() via OPUS_RESET_STATE
 (#2727)

This PR (https://github.com/youtube/cobalt/pull/2501) recreates
OpusAudioDecoder in OpusAudioDecoder::Reset(), as originally Cobalt
recreates OpusAudioDecoder on PartialAudio tests. Change to reset a
previously initialized state using the #OPUS_RESET_STATE CTL as stated
in the opus document.

b/327281974
---
 starboard/shared/opus/opus_audio_decoder.cc | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/starboard/shared/opus/opus_audio_decoder.cc b/starboard/shared/opus/opus_audio_decoder.cc
index 85ba47e6eb1f..fa8e00a69e2f 100644
--- a/starboard/shared/opus/opus_audio_decoder.cc
+++ b/starboard/shared/opus/opus_audio_decoder.cc
@@ -51,6 +51,9 @@ OpusAudioDecoder::OpusAudioDecoder(const AudioStreamInfo& audio_stream_info)
 }
 
 OpusAudioDecoder::~OpusAudioDecoder() {
+  if (is_valid()) {
+    opus_multistream_decoder_ctl(decoder_, OPUS_RESET_STATE);
+  }
   TeardownCodec();
 }
 
@@ -218,8 +221,9 @@ void OpusAudioDecoder::InitializeCodec() {
 }
 
 void OpusAudioDecoder::TeardownCodec() {
-  if (decoder_) {
+  if (is_valid()) {
     opus_multistream_decoder_destroy(decoder_);
+    decoder_ = NULL;
   }
 }
 
@@ -241,9 +245,19 @@ scoped_refptr<OpusAudioDecoder::DecodedAudio> OpusAudioDecoder::Read(
 void OpusAudioDecoder::Reset() {
   SB_DCHECK(BelongsToCurrentThread());
 
-  TeardownCodec();
-  InitializeCodec();
+  if (is_valid()) {
+    int error = opus_multistream_decoder_ctl(decoder_, OPUS_RESET_STATE);
+    if (error != OPUS_OK) {
+      SB_LOG(ERROR) << "Failed to reset OpusAudioDecoder with error: "
+                    << opus_strerror(error);
+
+      // If fail to reset opus decoder, re-create it.
+      TeardownCodec();
+      InitializeCodec();
+    }
+  }
 
+  frames_per_au_ = kMaxOpusFramesPerAU;
   stream_ended_ = false;
   while (!decoded_audios_.empty()) {
     decoded_audios_.pop();