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