Mixing audio with different latency requirements

media/base/audio_renderer_mixer_input.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/base/audio_renderer_mixer_input.h"
 
 #include <cmath>
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "media/base/audio_renderer_mixer.h"
 #include "media/base/audio_renderer_mixer_pool.h"
 
 namespace media {
 
 AudioRendererMixerInput::AudioRendererMixerInput(
     AudioRendererMixerPool* mixer_pool,
     int owner_id,
     const std::string& device_id,
-    const url::Origin& security_origin)
+    const url::Origin& security_origin,
+    AudioLatency::LatencyType latency)
     : mixer_pool_(mixer_pool),
       started_(false),
       playing_(false),
       volume_(1.0f),
       owner_id_(owner_id),
       device_id_(device_id),
       security_origin_(security_origin),
+      latency_(latency),
       mixer_(nullptr),
       callback_(nullptr),
       error_cb_(base::Bind(&AudioRendererMixerInput::OnRenderError,
                            base::Unretained(this))) {
   DCHECK(mixer_pool_);
 }
 
 AudioRendererMixerInput::~AudioRendererMixerInput() {
   DCHECK(!started_);
   DCHECK(!mixer_);
 }
 
 void AudioRendererMixerInput::Initialize(
     const AudioParameters& params,
     AudioRendererSink::RenderCallback* callback) {
   DCHECK(!started_);
   DCHECK(!mixer_);
   DCHECK(callback);
 
   params_ = params;
   callback_ = callback;
 }
 
 void AudioRendererMixerInput::Start() {
   DCHECK(!started_);
   DCHECK(!mixer_);
   DCHECK(callback_);  // Initialized.
 
   started_ = true;
-  mixer_ = mixer_pool_->GetMixer(owner_id_, params_, device_id_,
+  mixer_ = mixer_pool_->GetMixer(owner_id_, params_, latency_, device_id_,
                                  security_origin_, nullptr);
   if (!mixer_) {
     callback_->OnRenderError();
     return;
   }
 
   // Note: OnRenderError() may be called immediately after this call returns.
   mixer_->AddErrorCallback(error_cb_);
 
   if (!pending_switch_callback_.is_null()) {
     SwitchOutputDevice(pending_switch_device_id_,
                        pending_switch_security_origin_,
                        base::ResetAndReturn(&pending_switch_callback_));
   }
 }
 
 void AudioRendererMixerInput::Stop() {
   // Stop() may be called at any time, if Pause() hasn't been called we need to
   // remove our mixer input before shutdown.
   Pause();
 
   if (mixer_) {
     // TODO(dalecurtis): This is required so that |callback_| isn't called after
     // Stop() by an error event since it may outlive this ref-counted object. We
     // should instead have sane ownership semantics: http://crbug.com/151051
     mixer_->RemoveErrorCallback(error_cb_);
-    mixer_pool_->ReturnMixer(owner_id_, params_, device_id_, security_origin_);
+    mixer_pool_->ReturnMixer(mixer_);
     mixer_ = nullptr;
   }
 
   started_ = false;
 
   if (!pending_switch_callback_.is_null()) {
     base::ResetAndReturn(&pending_switch_callback_)
         .Run(OUTPUT_DEVICE_STATUS_ERROR_INTERNAL);
   }
 }
@@ skipping 47 matching lines @@
     return;
   }
 
   DCHECK(pending_switch_callback_.is_null());
   if (device_id == device_id_) {
     callback.Run(OUTPUT_DEVICE_STATUS_OK);
     return;
   }
 
   OutputDeviceStatus new_mixer_status = OUTPUT_DEVICE_STATUS_ERROR_INTERNAL;
-  AudioRendererMixer* new_mixer = mixer_pool_->GetMixer(
-      owner_id_, params_, device_id, security_origin, &new_mixer_status);
+  AudioRendererMixer* new_mixer =
+      mixer_pool_->GetMixer(owner_id_, params_, latency_, device_id,
+                            security_origin, &new_mixer_status);
   if (new_mixer_status != OUTPUT_DEVICE_STATUS_OK) {
     callback.Run(new_mixer_status);
     return;
   }
 
   bool was_playing = playing_;
   Stop();
   device_id_ = device_id;
   security_origin_ = security_origin;
   mixer_ = new_mixer;
@@ skipping 23 matching lines @@
     base::AutoLock auto_lock(volume_lock_);
     return frames_filled > 0 ? volume_ : 0;
   }
 }
 
 void AudioRendererMixerInput::OnRenderError() {
   callback_->OnRenderError();
 }
 
 }  // namespace media