content/browser/media/audio_stream_monitor.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/media/audio_stream_monitor.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "content/browser/web_contents/web_contents_impl.h"
  10 #include "content/public/browser/browser_thread.h"
  11 #include "content/public/browser/invalidate_type.h"
  12 #include "content/public/browser/render_frame_host.h"
  13
  14 namespace content {
  15
  16 namespace {
  17
  18 AudioStreamMonitor* AudioStreamMonitorFromRenderFrame(int render_process_id,
  19                                                       int render_frame_id) {
  20   DCHECK_CURRENTLY_ON(BrowserThread::UI);
  21   WebContentsImpl* const web_contents =
  22       static_cast<WebContentsImpl*>(WebContents::FromRenderFrameHost(
  23           RenderFrameHost::FromID(render_process_id, render_frame_id)));
  24
  25   return web_contents ? web_contents->audio_stream_monitor() : nullptr;
  26 }
  27
  28 }  // namespace
  29
  30 AudioStreamMonitor::AudioStreamMonitor(WebContents* contents)
  31     : web_contents_(contents),
  32       clock_(&default_tick_clock_),
  33       was_recently_audible_(false)
  34 {
  35   DCHECK(web_contents_);
  36 }
  37
  38 AudioStreamMonitor::~AudioStreamMonitor() {}
  39
  40 bool AudioStreamMonitor::WasRecentlyAudible() const {
  41   DCHECK(thread_checker_.CalledOnValidThread());
  42   return was_recently_audible_;
  43 }
  44
  45 // static
  46 void AudioStreamMonitor::StartMonitoringStream(
  47     int render_process_id,
  48     int render_frame_id,
  49     int stream_id,
  50     const ReadPowerAndClipCallback& read_power_callback) {
  51   if (!monitoring_available())
  52     return;
  53   BrowserThread::PostTask(BrowserThread::UI,
  54                           FROM_HERE,
  55                           base::Bind(&StartMonitoringHelper,
  56                                      render_process_id,
  57                                      render_frame_id,
  58                                      stream_id,
  59                                      read_power_callback));
  60 }
  61
  62 // static
  63 void AudioStreamMonitor::StopMonitoringStream(int render_process_id,
  64                                               int render_frame_id,
  65                                               int stream_id) {
  66   if (!media::AudioOutputController::will_monitor_audio_levels())
  67     return;
  68   BrowserThread::PostTask(BrowserThread::UI,
  69                           FROM_HERE,
  70                           base::Bind(&StopMonitoringHelper,
  71                                      render_process_id,
  72                                      render_frame_id,
  73                                      stream_id));
  74 }
  75
  76 // static
  77 void AudioStreamMonitor::StartMonitoringHelper(
  78     int render_process_id,
  79     int render_frame_id,
  80     int stream_id,
  81     const ReadPowerAndClipCallback& read_power_callback) {
  82   DCHECK_CURRENTLY_ON(BrowserThread::UI);
  83   AudioStreamMonitor* const monitor =
  84       AudioStreamMonitorFromRenderFrame(render_process_id, render_frame_id);
  85   if (monitor) {
  86     monitor->StartMonitoringStreamOnUIThread(
  87         render_process_id, stream_id, read_power_callback);
  88   }
  89 }
  90
  91 // static
  92 void AudioStreamMonitor::StopMonitoringHelper(int render_process_id,
  93                                               int render_frame_id,
  94                                               int stream_id) {
  95   DCHECK_CURRENTLY_ON(BrowserThread::UI);
  96   AudioStreamMonitor* const monitor =
  97       AudioStreamMonitorFromRenderFrame(render_process_id, render_frame_id);
  98   if (monitor)
  99     monitor->StopMonitoringStreamOnUIThread(render_process_id, stream_id);
 100 }
 101
 102 void AudioStreamMonitor::StartMonitoringStreamOnUIThread(
 103     int render_process_id,
 104     int stream_id,
 105     const ReadPowerAndClipCallback& read_power_callback) {
 106   DCHECK(thread_checker_.CalledOnValidThread());
 107   DCHECK(!read_power_callback.is_null());
 108   poll_callbacks_[StreamID(render_process_id, stream_id)] = read_power_callback;
 109   if (!poll_timer_.IsRunning()) {
 110     poll_timer_.Start(
 111         FROM_HERE,
 112         base::TimeDelta::FromSeconds(1) /
 113             static_cast<int>(kPowerMeasurementsPerSecond),
 114         base::Bind(&AudioStreamMonitor::Poll, base::Unretained(this)));
 115   }
 116 }
 117
 118 void AudioStreamMonitor::StopMonitoringStreamOnUIThread(int render_process_id,
 119                                                         int stream_id) {
 120   DCHECK(thread_checker_.CalledOnValidThread());
 121   poll_callbacks_.erase(StreamID(render_process_id, stream_id));
 122   if (poll_callbacks_.empty())
 123     poll_timer_.Stop();
 124 }
 125
 126 void AudioStreamMonitor::Poll() {
 127   for (StreamPollCallbackMap::const_iterator it = poll_callbacks_.begin();
 128        it != poll_callbacks_.end();
 129        ++it) {
 130     // TODO(miu): A new UI for delivering specific power level and clipping
 131     // information is still in the works.  For now, we throw away all
 132     // information except for "is it audible?"
 133     const float power_dbfs = it->second.Run().first;
 134     const float kSilenceThresholdDBFS = -72.24719896f;
 135     if (power_dbfs >= kSilenceThresholdDBFS) {
 136       last_blurt_time_ = clock_->NowTicks();
 137       MaybeToggle();
 138       break;  // No need to poll remaining streams.
 139     }
 140   }
 141 }
 142
 143 void AudioStreamMonitor::MaybeToggle() {
 144   const bool indicator_was_on = was_recently_audible_;
 145   const base::TimeTicks off_time =
 146       last_blurt_time_ + base::TimeDelta::FromMilliseconds(kHoldOnMilliseconds);
 147   const base::TimeTicks now = clock_->NowTicks();
 148   const bool should_indicator_be_on = now < off_time;
 149
 150   if (should_indicator_be_on != indicator_was_on) {
 151     was_recently_audible_ = should_indicator_be_on;
 152     web_contents_->NotifyNavigationStateChanged(INVALIDATE_TYPE_TAB);
 153   }
 154
 155   if (!should_indicator_be_on) {
 156     off_timer_.Stop();
 157   } else if (!off_timer_.IsRunning()) {
 158     off_timer_.Start(
 159         FROM_HERE,
 160         off_time - now,
 161         base::Bind(&AudioStreamMonitor::MaybeToggle, base::Unretained(this)));
 162   }
 163 }
 164
 165 }  // namespace content