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     : format_(AUDIO_PCM_LINEAR),
  14       channel_layout_(CHANNEL_LAYOUT_NONE),
  15       sample_rate_(0),
  16       bits_per_sample_(0),
  17       frames_per_buffer_(0),
  18       channels_(0),
  19       effects_(NO_EFFECTS) {
  20 }
  21
  22 AudioParameters::AudioParameters(Format format, ChannelLayout channel_layout,
  23                                  int sample_rate, int bits_per_sample,
  24                                  int frames_per_buffer)
  25     : format_(format),
  26       channel_layout_(channel_layout),
  27       sample_rate_(sample_rate),
  28       bits_per_sample_(bits_per_sample),
  29       frames_per_buffer_(frames_per_buffer),
  30       channels_(ChannelLayoutToChannelCount(channel_layout)),
  31       effects_(NO_EFFECTS) {
  32 }
  33
  34 AudioParameters::AudioParameters(Format format, ChannelLayout channel_layout,
  35                                  int sample_rate, int bits_per_sample,
  36                                  int frames_per_buffer, int effects)
  37     : format_(format),
  38       channel_layout_(channel_layout),
  39       sample_rate_(sample_rate),
  40       bits_per_sample_(bits_per_sample),
  41       frames_per_buffer_(frames_per_buffer),
  42       channels_(ChannelLayoutToChannelCount(channel_layout)),
  43       effects_(effects) {
  44 }
  45
  46 AudioParameters::AudioParameters(Format format, ChannelLayout channel_layout,
  47                                  int channels, int sample_rate,
  48                                  int bits_per_sample, int frames_per_buffer,
  49                                  int effects)
  50     : format_(format),
  51       channel_layout_(channel_layout),
  52       sample_rate_(sample_rate),
  53       bits_per_sample_(bits_per_sample),
  54       frames_per_buffer_(frames_per_buffer),
  55       channels_(channels),
  56       effects_(effects) {
  57   if (channel_layout != CHANNEL_LAYOUT_DISCRETE)
  58     DCHECK_EQ(channels, ChannelLayoutToChannelCount(channel_layout));
  59 }
  60
  61 void AudioParameters::Reset(Format format, ChannelLayout channel_layout,
  62                             int channels, int sample_rate,
  63                             int bits_per_sample, int frames_per_buffer) {
  64   if (channel_layout != CHANNEL_LAYOUT_DISCRETE)
  65     DCHECK_EQ(channels, ChannelLayoutToChannelCount(channel_layout));
  66
  67   format_ = format;
  68   channel_layout_ = channel_layout;
  69   channels_ = channels;
  70   sample_rate_ = sample_rate;
  71   bits_per_sample_ = bits_per_sample;
  72   frames_per_buffer_ = frames_per_buffer;
  73 }
  74
  75 bool AudioParameters::IsValid() const {
  76   return (format_ >= AUDIO_PCM_LINEAR) &&
  77          (format_ < AUDIO_LAST_FORMAT) &&
  78          (channels_ > 0) &&
  79          (channels_ <= media::limits::kMaxChannels) &&
  80          (channel_layout_ > CHANNEL_LAYOUT_UNSUPPORTED) &&
  81          (channel_layout_ <= CHANNEL_LAYOUT_MAX) &&
  82          (sample_rate_ >= media::limits::kMinSampleRate) &&
  83          (sample_rate_ <= media::limits::kMaxSampleRate) &&
  84          (bits_per_sample_ > 0) &&
  85          (bits_per_sample_ <= media::limits::kMaxBitsPerSample) &&
  86          (frames_per_buffer_ > 0) &&
  87          (frames_per_buffer_ <= media::limits::kMaxSamplesPerPacket);
  88 }
  89
  90 std::string AudioParameters::AsHumanReadableString() const {
  91   std::ostringstream s;
  92   s << "format: " << format()
  93     << " channels: " << channels()
  94     << " channel_layout: " << channel_layout()
  95     << " sample_rate: " << sample_rate()
  96     << " bits_per_sample: " << bits_per_sample()
  97     << " frames_per_buffer: " << frames_per_buffer();
  98   return s.str();
  99 }
 100
 101 int AudioParameters::GetBytesPerBuffer() const {
 102   return frames_per_buffer_ * GetBytesPerFrame();
 103 }
 104
 105 int AudioParameters::GetBytesPerSecond() const {
 106   return sample_rate_ * GetBytesPerFrame();
 107 }
 108
 109 int AudioParameters::GetBytesPerFrame() const {
 110   return channels_ * bits_per_sample_ / 8;
 111 }
 112
 113 base::TimeDelta AudioParameters::GetBufferDuration() const {
 114   return base::TimeDelta::FromMicroseconds(static_cast<int64>(
 115       frames_per_buffer_ * base::Time::kMicrosecondsPerSecond /
 116       static_cast<float>(sample_rate_)));
 117 }
 118
 119 bool AudioParameters::Equals(const AudioParameters& other) const {
 120   return format_ == other.format() &&
 121          sample_rate_ == other.sample_rate() &&
 122          channel_layout_ == other.channel_layout() &&
 123          channels_ == other.channels() &&
 124          bits_per_sample_ == other.bits_per_sample() &&
 125          frames_per_buffer_ == other.frames_per_buffer() &&
 126          effects_ == other.effects();
 127 }
 128
 129 }  // namespace media