Have AudioRendererImpl advance time until it's told to stop.

media/filters/audio_clock_unittest.cc

 // Copyright 2014 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_timestamp_helper.h"
 #include "media/base/buffers.h"
 #include "media/filters/audio_clock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace media {
 
 class AudioClockTest : public testing::Test {
  public:
   AudioClockTest()
       : sample_rate_(10), clock_(base::TimeDelta(), sample_rate_) {}
 
   virtual ~AudioClockTest() {}
 
   void WroteAudio(int frames_written,
                   int frames_requested,
                   int delay_frames,
                   float playback_rate) {
     clock_.WroteAudio(
         frames_written, frames_requested, delay_frames, playback_rate);
   }
 
-  int CurrentMediaTimestampInDays() {
-    return clock_.current_media_timestamp().InDays();
+  int FrontTimestampInDays() { return clock_.front_timestamp().InDays(); }
+
+  int FrontTimestampInMilliseconds() {
+    return clock_.front_timestamp().InMilliseconds();
   }
 
-  int CurrentMediaTimestampInMilliseconds() {
-    return clock_.current_media_timestamp().InMilliseconds();
+  int BackTimestampInMilliseconds() {
+    return clock_.back_timestamp().InMilliseconds();
   }
 
-  int CurrentMediaTimestampSinceLastWritingInMilliseconds(int milliseconds) {
-    return clock_.CurrentMediaTimestampSinceWriting(
-                      base::TimeDelta::FromMilliseconds(milliseconds))
-        .InMilliseconds();
+  int TimestampSinceLastWritingInMilliseconds(int milliseconds) {
+    return clock_.TimestampSinceWriting(base::TimeDelta::FromMilliseconds(
+                                            milliseconds)).InMilliseconds();
   }
 
   int ContiguousAudioDataBufferedInDays() {
     return clock_.contiguous_audio_data_buffered().InDays();
   }
 
   int ContiguousAudioDataBufferedInMilliseconds() {
     return clock_.contiguous_audio_data_buffered().InMilliseconds();
   }
 
   int ContiguousAudioDataBufferedAtSameRateInMilliseconds() {
     return clock_.contiguous_audio_data_buffered_at_same_rate()
         .InMilliseconds();
   }
 
   const int sample_rate_;
   AudioClock clock_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AudioClockTest);
 };
 
-TEST_F(AudioClockTest, CurrentMediaTimestampStartsAtStartTimestamp) {
+TEST_F(AudioClockTest, FrontTimestampStartsAtStartTimestamp) {
   base::TimeDelta expected = base::TimeDelta::FromSeconds(123);
   AudioClock clock(expected, sample_rate_);
 
-  EXPECT_EQ(expected, clock.current_media_timestamp());
+  EXPECT_EQ(expected, clock.front_timestamp());
 }
 
-TEST_F(AudioClockTest,
-       CurrentMediaTimestampSinceWritingStartsAtStartTimestamp) {
+TEST_F(AudioClockTest, BackTimestampStartsAtStartTimestamp) {
+  base::TimeDelta expected = base::TimeDelta::FromSeconds(123);
+  AudioClock clock(expected, sample_rate_);
+
+  EXPECT_EQ(expected, clock.back_timestamp());
+}
+
+TEST_F(AudioClockTest, TimestampSinceWritingStartsAtStartTimestamp) {
   base::TimeDelta expected = base::TimeDelta::FromSeconds(123);
   AudioClock clock(expected, sample_rate_);
 
   base::TimeDelta time_since_writing = base::TimeDelta::FromSeconds(456);
-  EXPECT_EQ(expected,
-            clock.CurrentMediaTimestampSinceWriting(time_since_writing));
+  EXPECT_EQ(expected, clock.TimestampSinceWriting(time_since_writing));
 }
 
 TEST_F(AudioClockTest, ContiguousAudioDataBufferedStartsAtZero) {
   EXPECT_EQ(base::TimeDelta(), clock_.contiguous_audio_data_buffered());
 }
 
 TEST_F(AudioClockTest, ContiguousAudioDataBufferedAtSameRateStartsAtZero) {
   EXPECT_EQ(base::TimeDelta(),
             clock_.contiguous_audio_data_buffered_at_same_rate());
 }
 
-TEST_F(AudioClockTest, AudioDataBufferedStartsAtFalse) {
-  EXPECT_FALSE(clock_.audio_data_buffered());
-}
-
 TEST_F(AudioClockTest, Playback) {
   // The first time we write data we should still expect our start timestamp
   // due to delay.
   WroteAudio(10, 10, 20, 1.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(0, FrontTimestampInMilliseconds());
+  EXPECT_EQ(1000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
-  EXPECT_TRUE(clock_.audio_data_buffered());
 
   // The media time should remain at start timestamp as we write data.
   WroteAudio(10, 10, 20, 1.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(0, FrontTimestampInMilliseconds());
+  EXPECT_EQ(2000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(10, 10, 20, 1.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(0, FrontTimestampInMilliseconds());
+  EXPECT_EQ(3000, BackTimestampInMilliseconds());
   EXPECT_EQ(3000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(3000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   // The media time should now start advanced now that delay has been covered.
   WroteAudio(10, 10, 20, 1.0);
-  EXPECT_EQ(1000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(1000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(4000, BackTimestampInMilliseconds());
   EXPECT_EQ(3000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(3000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(10, 10, 20, 1.0);
-  EXPECT_EQ(2000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(2000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(5000, BackTimestampInMilliseconds());
   EXPECT_EQ(3000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(3000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   // Introduce a rate change to slow down time:
   //   - Current time will advance by one second until it hits rate change
   //   - Contiguous audio data will start shrinking immediately
   WroteAudio(10, 10, 20, 0.5);
-  EXPECT_EQ(3000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(3000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(5500, BackTimestampInMilliseconds());
   EXPECT_EQ(2500, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(2000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(10, 10, 20, 0.5);
-  EXPECT_EQ(4000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(4000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(6000, BackTimestampInMilliseconds());
   EXPECT_EQ(2000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(1000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(10, 10, 20, 0.5);
-  EXPECT_EQ(5000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(5000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(6500, BackTimestampInMilliseconds());
   EXPECT_EQ(1500, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(1500, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(10, 10, 20, 0.5);
-  EXPECT_EQ(5500, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(5500, FrontTimestampInMilliseconds());
+  EXPECT_EQ(7000, BackTimestampInMilliseconds());
   EXPECT_EQ(1500, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(1500, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   // Introduce a rate change to speed up time:
   //   - Current time will advance by half a second until it hits rate change
   //   - Contiguous audio data will start growing immediately
   WroteAudio(10, 10, 20, 2);
-  EXPECT_EQ(6000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(6000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(9000, BackTimestampInMilliseconds());
   EXPECT_EQ(3000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(1000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(10, 10, 20, 2);
-  EXPECT_EQ(6500, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(6500, FrontTimestampInMilliseconds());
+  EXPECT_EQ(11000, BackTimestampInMilliseconds());
   EXPECT_EQ(4500, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(500, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(10, 10, 20, 2);
-  EXPECT_EQ(7000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(7000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(13000, BackTimestampInMilliseconds());
   EXPECT_EQ(6000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(6000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(10, 10, 20, 2);
-  EXPECT_EQ(9000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(9000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(15000, BackTimestampInMilliseconds());
   EXPECT_EQ(6000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(6000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   // Write silence to simulate reaching end of stream:
   //   - Current time will advance by half a second until it hits silence
   //   - Contiguous audio data will start shrinking towards zero
   WroteAudio(0, 10, 20, 2);
-  EXPECT_EQ(11000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(11000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(15000, BackTimestampInMilliseconds());
   EXPECT_EQ(4000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(4000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
 
   WroteAudio(0, 10, 20, 2);
-  EXPECT_EQ(13000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(13000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(15000, BackTimestampInMilliseconds());
   EXPECT_EQ(2000, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(2000, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
-  EXPECT_TRUE(clock_.audio_data_buffered());  // Still audio data buffered.
 
   WroteAudio(0, 10, 20, 2);
-  EXPECT_EQ(15000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(15000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(15000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
-  EXPECT_FALSE(clock_.audio_data_buffered());  // No more audio data buffered.
 
   // At this point media time should stop increasing.
   WroteAudio(0, 10, 20, 2);
-  EXPECT_EQ(15000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(15000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(15000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedAtSameRateInMilliseconds());
-  EXPECT_FALSE(clock_.audio_data_buffered());
 }
 
 TEST_F(AudioClockTest, AlternatingAudioAndSilence) {
   // Buffer #1: [0, 1000)
   WroteAudio(10, 10, 20, 1.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(0, FrontTimestampInMilliseconds());
+  EXPECT_EQ(1000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
 
   // Buffer #2: 1000ms of silence
   WroteAudio(0, 10, 20, 1.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(0, FrontTimestampInMilliseconds());
+  EXPECT_EQ(1000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
 
   // Buffer #3: [1000, 2000):
   //   - Buffer #1 is at front with 1000ms of contiguous audio data
   WroteAudio(10, 10, 20, 1.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(0, FrontTimestampInMilliseconds());
+  EXPECT_EQ(2000, BackTimestampInMilliseconds());
   EXPECT_EQ(1000, ContiguousAudioDataBufferedInMilliseconds());
 
   // Buffer #4: 1000ms of silence
   //   - Buffer #1 has been played out
   //   - Buffer #2 of silence leaves us with 0ms of contiguous audio data
   WroteAudio(0, 10, 20, 1.0);
-  EXPECT_EQ(1000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(1000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(2000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
 
   // Buffer #5: [2000, 3000):
   //   - Buffer #3 is at front with 1000ms of contiguous audio data
   WroteAudio(10, 10, 20, 1.0);
-  EXPECT_EQ(1000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(1000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(3000, BackTimestampInMilliseconds());
   EXPECT_EQ(1000, ContiguousAudioDataBufferedInMilliseconds());
 }
 
 TEST_F(AudioClockTest, ZeroDelay) {
   // The first time we write data we should expect the first timestamp
   // immediately.
   WroteAudio(10, 10, 0, 1.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(0, FrontTimestampInMilliseconds());
+  EXPECT_EQ(1000, BackTimestampInMilliseconds());
   EXPECT_EQ(1000, ContiguousAudioDataBufferedInMilliseconds());
 
   // Ditto for all subsequent buffers.
   WroteAudio(10, 10, 0, 1.0);
-  EXPECT_EQ(1000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(1000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(2000, BackTimestampInMilliseconds());
   EXPECT_EQ(1000, ContiguousAudioDataBufferedInMilliseconds());
 
   WroteAudio(10, 10, 0, 1.0);
-  EXPECT_EQ(2000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(2000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(3000, BackTimestampInMilliseconds());
   EXPECT_EQ(1000, ContiguousAudioDataBufferedInMilliseconds());
 
   // Ditto for silence.
   WroteAudio(0, 10, 0, 1.0);
-  EXPECT_EQ(3000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(3000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(3000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
 
   WroteAudio(0, 10, 0, 1.0);
-  EXPECT_EQ(3000, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(3000, FrontTimestampInMilliseconds());
+  EXPECT_EQ(3000, BackTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
 }
 
-TEST_F(AudioClockTest, CurrentMediaTimestampSinceLastWriting) {
+TEST_F(AudioClockTest, TimestampSinceLastWriting) {
   // Construct an audio clock with the following representation:
   //
   // +-------------------+----------------+------------------+----------------+
   // | 10 frames silence | 10 frames @ 1x | 10 frames @ 0.5x | 10 frames @ 2x |
   // +-------------------+----------------+------------------+----------------+
   // Media timestamp:    0              1000               1500             3500
   // Wall clock time:  2000             3000               4000             5000
   WroteAudio(10, 10, 40, 1.0);
   WroteAudio(10, 10, 40, 0.5);
   WroteAudio(10, 10, 40, 2.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInMilliseconds());
+  EXPECT_EQ(0, FrontTimestampInMilliseconds());
   EXPECT_EQ(0, ContiguousAudioDataBufferedInMilliseconds());
 
   // Simulate passing 2000ms of initial delay in the audio hardware.
-  EXPECT_EQ(0, CurrentMediaTimestampSinceLastWritingInMilliseconds(0));
-  EXPECT_EQ(0, CurrentMediaTimestampSinceLastWritingInMilliseconds(500));
-  EXPECT_EQ(0, CurrentMediaTimestampSinceLastWritingInMilliseconds(1000));
-  EXPECT_EQ(0, CurrentMediaTimestampSinceLastWritingInMilliseconds(1500));
-  EXPECT_EQ(0, CurrentMediaTimestampSinceLastWritingInMilliseconds(2000));
+  EXPECT_EQ(0, TimestampSinceLastWritingInMilliseconds(0));
+  EXPECT_EQ(0, TimestampSinceLastWritingInMilliseconds(500));
+  EXPECT_EQ(0, TimestampSinceLastWritingInMilliseconds(1000));
+  EXPECT_EQ(0, TimestampSinceLastWritingInMilliseconds(1500));
+  EXPECT_EQ(0, TimestampSinceLastWritingInMilliseconds(2000));
 
   // Now we should see the 1.0x buffer.
-  EXPECT_EQ(500, CurrentMediaTimestampSinceLastWritingInMilliseconds(2500));
-  EXPECT_EQ(1000, CurrentMediaTimestampSinceLastWritingInMilliseconds(3000));
+  EXPECT_EQ(500, TimestampSinceLastWritingInMilliseconds(2500));
+  EXPECT_EQ(1000, TimestampSinceLastWritingInMilliseconds(3000));
 
   // Now we should see the 0.5x buffer.
-  EXPECT_EQ(1250, CurrentMediaTimestampSinceLastWritingInMilliseconds(3500));
-  EXPECT_EQ(1500, CurrentMediaTimestampSinceLastWritingInMilliseconds(4000));
+  EXPECT_EQ(1250, TimestampSinceLastWritingInMilliseconds(3500));
+  EXPECT_EQ(1500, TimestampSinceLastWritingInMilliseconds(4000));
 
   // Now we should see the 2.0x buffer.
-  EXPECT_EQ(2500, CurrentMediaTimestampSinceLastWritingInMilliseconds(4500));
-  EXPECT_EQ(3500, CurrentMediaTimestampSinceLastWritingInMilliseconds(5000));
+  EXPECT_EQ(2500, TimestampSinceLastWritingInMilliseconds(4500));
+  EXPECT_EQ(3500, TimestampSinceLastWritingInMilliseconds(5000));
 
   // Times beyond the known length of the audio clock should return the last
   // media timestamp we know of.
-  EXPECT_EQ(3500, CurrentMediaTimestampSinceLastWritingInMilliseconds(5001));
-  EXPECT_EQ(3500, CurrentMediaTimestampSinceLastWritingInMilliseconds(6000));
+  EXPECT_EQ(3500, TimestampSinceLastWritingInMilliseconds(5001));
+  EXPECT_EQ(3500, TimestampSinceLastWritingInMilliseconds(6000));
 }
 
 TEST_F(AudioClockTest, SupportsYearsWorthOfAudioData) {
   // Use number of frames that would be likely to overflow 32-bit integer math.
   const int huge_amount_of_frames = std::numeric_limits<int>::max();
   const base::TimeDelta huge =
       base::TimeDelta::FromSeconds(huge_amount_of_frames / sample_rate_);
   EXPECT_EQ(2485, huge.InDays());  // Just to give some context on how big...
 
   // Use zero delay to test calculation of current timestamp.
   WroteAudio(huge_amount_of_frames, huge_amount_of_frames, 0, 1.0);
-  EXPECT_EQ(0, CurrentMediaTimestampInDays());
+  EXPECT_EQ(0, FrontTimestampInDays());
   EXPECT_EQ(2485, ContiguousAudioDataBufferedInDays());
 
   WroteAudio(huge_amount_of_frames, huge_amount_of_frames, 0, 1.0);
-  EXPECT_EQ(huge.InDays(), CurrentMediaTimestampInDays());
+  EXPECT_EQ(huge.InDays(), FrontTimestampInDays());
   EXPECT_EQ(huge.InDays(), ContiguousAudioDataBufferedInDays());
 
   WroteAudio(huge_amount_of_frames, huge_amount_of_frames, 0, 1.0);
-  EXPECT_EQ((huge * 2).InDays(), CurrentMediaTimestampInDays());
+  EXPECT_EQ((huge * 2).InDays(), FrontTimestampInDays());
   EXPECT_EQ(huge.InDays(), ContiguousAudioDataBufferedInDays());
 
   WroteAudio(huge_amount_of_frames, huge_amount_of_frames, 0, 1.0);
-  EXPECT_EQ((huge * 3).InDays(), CurrentMediaTimestampInDays());
+  EXPECT_EQ((huge * 3).InDays(), FrontTimestampInDays());
   EXPECT_EQ(huge.InDays(), ContiguousAudioDataBufferedInDays());
 
   // Use huge delay to test calculation of buffered data.
   WroteAudio(
       huge_amount_of_frames, huge_amount_of_frames, huge_amount_of_frames, 1.0);
-  EXPECT_EQ((huge * 3).InDays(), CurrentMediaTimestampInDays());
+  EXPECT_EQ((huge * 3).InDays(), FrontTimestampInDays());
   EXPECT_EQ((huge * 2).InDays(), ContiguousAudioDataBufferedInDays());
 }
 
 }  // namespace media