chrome/browser/media/webrtc_browsertest_audio.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 "chrome/browser/media/webrtc_browsertest_audio.h"
   6
   7 #include "base/files/file.h"
   8 #include "base/files/file_path.h"
   9 #include "media/audio/audio_power_monitor.h"
  10 #include "media/audio/sounds/wav_audio_handler.h"
  11 #include "media/base/audio_bus.h"
  12
  13 namespace {
  14 // Opens |wav_filename|, reads it and loads it as a wav file. This function will
  15 // bluntly trigger CHECKs if we can't read the file or if it's malformed. The
  16 // caller takes ownership of the returned data. The size of the data is stored
  17 // in |read_length|.
  18 scoped_ptr<uint8[]> ReadWavFile(const base::FilePath& wav_filename,
  19                                 size_t* file_length) {
  20   base::File wav_file(
  21       wav_filename, base::File::FLAG_OPEN | base::File::FLAG_READ);
  22   if (!wav_file.IsValid()) {
  23     CHECK(false) << "Failed to read " << wav_filename.value();
  24     return nullptr;
  25   }
  26
  27   size_t wav_file_length = wav_file.GetLength();
  28
  29   uint8* wav_file_data = new uint8[wav_file_length];
  30   size_t read_bytes = wav_file.Read(0, reinterpret_cast<char*>(wav_file_data),
  31                                     wav_file_length);
  32   if (read_bytes != wav_file_length) {
  33     CHECK(false) << "Failed to read all bytes of " << wav_filename.value();
  34     return nullptr;
  35   }
  36   *file_length = wav_file_length;
  37   return scoped_ptr<uint8[]>(wav_file_data);
  38 }
  39
  40 scoped_ptr<media::WavAudioHandler> CreateWavAudioHandler(
  41     const base::FilePath& wav_filename, const uint8* wav_file_data,
  42     size_t wav_file_length) {
  43   base::StringPiece wav_data(reinterpret_cast<const char*>(wav_file_data),
  44                              wav_file_length);
  45   scoped_ptr<media::WavAudioHandler> wav_audio_handler(
  46       new media::WavAudioHandler(wav_data));
  47
  48   return wav_audio_handler.Pass();
  49 }
  50
  51 }  // namespace
  52
  53 namespace test {
  54
  55 float ComputeAudioEnergyForWavFile(const base::FilePath& wav_filename,
  56                                    media::AudioParameters* file_parameters) {
  57   // Read the file, and put its data in a scoped_ptr so it gets deleted later.
  58   size_t file_length = 0;
  59   scoped_ptr<uint8[]> wav_file_data = ReadWavFile(wav_filename, &file_length);
  60   scoped_ptr<media::WavAudioHandler> wav_audio_handler = CreateWavAudioHandler(
  61       wav_filename, wav_file_data.get(), file_length);
  62
  63   scoped_ptr<media::AudioBus> audio_bus =
  64       media::AudioBus::Create(wav_audio_handler->params());
  65   base::TimeDelta file_duration =
  66       wav_audio_handler->params().GetBufferDuration();
  67
  68   size_t bytes_written;
  69   wav_audio_handler->CopyTo(audio_bus.get(), 0, &bytes_written);
  70   CHECK_EQ(bytes_written, wav_audio_handler->data().size())
  71       << "Expected to write entire file into bus.";
  72
  73   // Set the filter coefficient to the whole file's duration; this will make the
  74   // power monitor take the entire file into account.
  75   media::AudioPowerMonitor power_monitor(
  76       wav_audio_handler->params().sample_rate(), file_duration);
  77   power_monitor.Scan(*audio_bus, audio_bus->frames());
  78
  79   *file_parameters = wav_audio_handler->params();
  80   return power_monitor.ReadCurrentPowerAndClip().first;
  81 }
  82
  83 }  // namespace test