media/audio/audio_parameters.cc

   1 // Copyright (c) 2012 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 "media/audio/audio_parameters.h"
   6
   7 #include "base/logging.h"
   8 #include "media/base/limits.h"
   9
  10 namespace media {
  11
  12 AudioParameters::AudioParameters()
  13     : AudioParameters(AUDIO_PCM_LINEAR, CHANNEL_LAYOUT_NONE, 0, 0, 0) {}
  14
  15 AudioParameters::AudioParameters(Format format,
  16                                  ChannelLayout channel_layout,
  17                                  int sample_rate,
  18                                  int bits_per_sample,
  19                                  int frames_per_buffer) {
  20   Reset(format, channel_layout, sample_rate, bits_per_sample,
  21         frames_per_buffer);
  22 }
  23
  24 AudioParameters::~AudioParameters() {}
  25
  26 AudioParameters::AudioParameters(const AudioParameters&) = default;
  27 AudioParameters& AudioParameters::operator=(const AudioParameters&) = default;
  28
  29 void AudioParameters::Reset(Format format,
  30                             ChannelLayout channel_layout,
  31                             int sample_rate,
  32                             int bits_per_sample,
  33                             int frames_per_buffer) {
  34   format_ = format;
  35   channel_layout_ = channel_layout;
  36   channels_ = ChannelLayoutToChannelCount(channel_layout);
  37   sample_rate_ = sample_rate;
  38   bits_per_sample_ = bits_per_sample;
  39   frames_per_buffer_ = frames_per_buffer;
  40   effects_ = NO_EFFECTS;
  41   mic_positions_.clear();
  42 }
  43
  44 bool AudioParameters::IsValid() const {
  45   return (channels_ > 0) && (channels_ <= media::limits::kMaxChannels) &&
  46          (channel_layout_ > CHANNEL_LAYOUT_UNSUPPORTED) &&
  47          (sample_rate_ >= media::limits::kMinSampleRate) &&
  48          (sample_rate_ <= media::limits::kMaxSampleRate) &&
  49          (bits_per_sample_ > 0) &&
  50          (bits_per_sample_ <= media::limits::kMaxBitsPerSample) &&
  51          (frames_per_buffer_ > 0) &&
  52          (frames_per_buffer_ <= media::limits::kMaxSamplesPerPacket) &&
  53          (channel_layout_ == CHANNEL_LAYOUT_DISCRETE ||
  54           channels_ == ChannelLayoutToChannelCount(channel_layout_));
  55 }
  56
  57 std::string AudioParameters::AsHumanReadableString() const {
  58   std::ostringstream s;
  59   s << "format: " << format() << " channel_layout: " << channel_layout()
  60     << " channels: " << channels() << " sample_rate: " << sample_rate()
  61     << " bits_per_sample: " << bits_per_sample()
  62     << " frames_per_buffer: " << frames_per_buffer()
  63     << " effects: " << effects()
  64     << " mic_positions: " << PointsToString(mic_positions_);
  65   return s.str();
  66 }
  67
  68 int AudioParameters::GetBytesPerBuffer() const {
  69   return frames_per_buffer_ * GetBytesPerFrame();
  70 }
  71
  72 int AudioParameters::GetBytesPerSecond() const {
  73   return sample_rate_ * GetBytesPerFrame();
  74 }
  75
  76 int AudioParameters::GetBytesPerFrame() const {
  77   return channels_ * bits_per_sample_ / 8;
  78 }
  79
  80 base::TimeDelta AudioParameters::GetBufferDuration() const {
  81   return base::TimeDelta::FromMicroseconds(static_cast<int64>(
  82       frames_per_buffer_ * base::Time::kMicrosecondsPerSecond /
  83       static_cast<float>(sample_rate_)));
  84 }
  85
  86 bool AudioParameters::Equals(const AudioParameters& other) const {
  87   return format_ == other.format() && sample_rate_ == other.sample_rate() &&
  88          channel_layout_ == other.channel_layout() &&
  89          channels_ == other.channels() &&
  90          bits_per_sample_ == other.bits_per_sample() &&
  91          frames_per_buffer_ == other.frames_per_buffer() &&
  92          effects_ == other.effects() && mic_positions_ == other.mic_positions_;
  93 }
  94
  95 }  // namespace media