[Chromecast] Fix fade-out frames in ALSA mixer

chromecast/media/cma/backend/alsa/stream_mixer_alsa_input_impl.cc

Index: chromecast/media/cma/backend/alsa/stream_mixer_alsa_input_impl.cc
diff --git a/chromecast/media/cma/backend/alsa/stream_mixer_alsa_input_impl.cc b/chromecast/media/cma/backend/alsa/stream_mixer_alsa_input_impl.cc
index 0a8f0a462da7a4550cd0060682e3d5ac05139214..1e7cc895cc43fcefb9ff7106d9cf1178d2614106 100644
--- a/chromecast/media/cma/backend/alsa/stream_mixer_alsa_input_impl.cc
+++ b/chromecast/media/cma/backend/alsa/stream_mixer_alsa_input_impl.cc
@@ -69,6 +69,7 @@ StreamMixerAlsaInputImpl::StreamMixerAlsaInputImpl(
       mixer_(mixer),
       mixer_task_runner_(mixer_->task_runner()),
       caller_task_runner_(base::ThreadTaskRunnerHandle::Get()),
+      resample_ratio_(1.0),
       state_(kStateUninitialized),
       volume_multiplier_(1.0f),
       queued_frames_(0),
@@ -80,12 +81,14 @@ StreamMixerAlsaInputImpl::StreamMixerAlsaInputImpl(
       fade_out_frames_total_(0),
       zeroed_frames_(0),
       weak_factory_(this) {
+  LOG(INFO) << "Create " << this;
   DCHECK(delegate_);
   DCHECK(mixer_);
   weak_this_ = weak_factory_.GetWeakPtr();
 }
 
 StreamMixerAlsaInputImpl::~StreamMixerAlsaInputImpl() {
+  LOG(INFO) << "Destroy " << this;
   DCHECK(mixer_task_runner_->BelongsToCurrentThread());
 }
 
@@ -111,10 +114,10 @@ void StreamMixerAlsaInputImpl::Initialize(
   DCHECK(mixer_task_runner_->BelongsToCurrentThread());
   DCHECK(!IsDeleting());
   if (mixer_->output_samples_per_second() != input_samples_per_second_) {
-    double resample_ratio = static_cast<double>(input_samples_per_second_) /
-                            mixer_->output_samples_per_second();
+    resample_ratio_ = static_cast<double>(input_samples_per_second_) /
+                      mixer_->output_samples_per_second();
     resampler_.reset(new ::media::MultiChannelResampler(
-        kNumOutputChannels, resample_ratio, kDefaultReadSize,
+        kNumOutputChannels, resample_ratio_, kDefaultReadSize,
         base::Bind(&StreamMixerAlsaInputImpl::ReadCB, base::Unretained(this))));
     resampler_->PrimeWithSilence();
   }
@@ -146,11 +149,14 @@ void StreamMixerAlsaInputImpl::PrepareToDelete(
   {
     base::AutoLock lock(queue_lock_);
     if (state_ == kStateGotEos) {
-      fade_out_frames_total_ = queued_frames_including_resampler_;
-      fade_frames_remaining_ = queued_frames_including_resampler_;
+      fade_out_frames_total_ =
+          queued_frames_including_resampler_ / resample_ratio_;
+      fade_frames_remaining_ =
+          queued_frames_including_resampler_ / resample_ratio_;
     } else if (state_ == kStateNormalPlayback) {
       fade_out_frames_total_ =
-          std::min(static_cast<int>(queued_frames_including_resampler_),
+          std::min(static_cast<int>(queued_frames_including_resampler_ /
+                                    resample_ratio_),
                    NormalFadeFrames());
       fade_frames_remaining_ = fade_out_frames_total_;
     }
@@ -221,6 +227,7 @@ void StreamMixerAlsaInputImpl::DidQueueData(bool end_of_stream) {
   RUN_ON_MIXER_THREAD(DidQueueData, end_of_stream);
   DCHECK(!IsDeleting());
   if (end_of_stream) {
+    LOG(INFO) << "End of stream for " << this;
     state_ = kStateGotEos;
   } else if (state_ == kStateUninitialized) {
     state_ = kStateNormalPlayback;
@@ -240,9 +247,10 @@ void StreamMixerAlsaInputImpl::AfterWriteFrames(
     base::AutoLock lock(queue_lock_);
     mixer_rendering_delay_ = mixer_rendering_delay;
     queued_frames_ = 0;
-    for (const auto& data : queue_)
+    for (const auto& data : queue_) {
       queued_frames_ +=
           data->data_size() / (kNumOutputChannels * sizeof(float));
+    }
     queued_frames_ -= current_buffer_offset_;
     DCHECK_GE(queued_frames_, 0);
     queued_frames_including_resampler_ =
@@ -253,8 +261,10 @@ void StreamMixerAlsaInputImpl::AfterWriteFrames(
       pending_data_ = nullptr;
       total_delay = QueueData(data);
       queued_more_data = true;
-      if (data->end_of_stream())
+      if (data->end_of_stream()) {
+        LOG(INFO) << "End of stream for " << this;
         state_ = kStateGotEos;
+      }
     }
   }
 
@@ -273,7 +283,8 @@ int StreamMixerAlsaInputImpl::MaxReadSize() {
   {
     base::AutoLock lock(queue_lock_);
     if (state_ == kStateGotEos)
-      return std::max(static_cast<int>(queued_frames_including_resampler_),
+      return std::max(static_cast<int>(queued_frames_including_resampler_ /
+                                       resample_ratio_),
                       kDefaultReadSize);
     queued_frames = queued_frames_;
   }
@@ -368,12 +379,13 @@ void StreamMixerAlsaInputImpl::FillFrames(int frame_delay,
       }
       frames_left -= frames_to_copy;
       frames_filled += frames_to_copy;
-      LOG_IF(WARNING, zeroed_frames_ > 0) << "Filled a total of "
-                                          << zeroed_frames_ << " frames with 0";
+      LOG_IF(WARNING, state_ != kStateFinalFade && zeroed_frames_ > 0)
+          << "Filled a total of " << zeroed_frames_ << " frames with 0";
       zeroed_frames_ = 0;
     } else {
       // No data left in queue; fill remaining frames with zeros.
-      LOG_IF(WARNING, zeroed_frames_ == 0) << "Starting to fill frames with 0";
+      LOG_IF(WARNING, state_ != kStateFinalFade && zeroed_frames_ == 0)
+          << "Starting to fill frames with 0";
       zeroed_frames_ += frames_left;
       output->ZeroFramesPartial(frames_filled, frames_left);
       frames_filled += frames_left;
@@ -485,6 +497,7 @@ void StreamMixerAlsaInputImpl::SetPaused(bool paused) {
 
 void StreamMixerAlsaInputImpl::SetVolumeMultiplier(float multiplier) {
   RUN_ON_MIXER_THREAD(SetVolumeMultiplier, multiplier);
+  LOG(INFO) << this << ": stream volume = " << multiplier;
   DCHECK(!IsDeleting());
   if (multiplier > 1.0f)
     multiplier = 1.0f;