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 void AudioParameters::Reset(Format format,
  25                             ChannelLayout channel_layout,
  26                             int sample_rate,
  27                             int bits_per_sample,
  28                             int frames_per_buffer) {
  29   format_ = format;
  30   channel_layout_ = channel_layout;
  31   channels_ = ChannelLayoutToChannelCount(channel_layout);
  32   sample_rate_ = sample_rate;
  33   bits_per_sample_ = bits_per_sample;
  34   frames_per_buffer_ = frames_per_buffer;
  35   effects_ = NO_EFFECTS;
  36 }
  37
  38 bool AudioParameters::IsValid() const {
  39   return (channels_ > 0) && (channels_ <= media::limits::kMaxChannels) &&
  40          (channel_layout_ > CHANNEL_LAYOUT_UNSUPPORTED) &&
  41          (sample_rate_ >= media::limits::kMinSampleRate) &&
  42          (sample_rate_ <= media::limits::kMaxSampleRate) &&
  43          (bits_per_sample_ > 0) &&
  44          (bits_per_sample_ <= media::limits::kMaxBitsPerSample) &&
  45          (frames_per_buffer_ > 0) &&
  46          (frames_per_buffer_ <= media::limits::kMaxSamplesPerPacket) &&
  47          (channel_layout_ == CHANNEL_LAYOUT_DISCRETE ||
  48           channels_ == ChannelLayoutToChannelCount(channel_layout_));
  49 }
  50
  51 std::string AudioParameters::AsHumanReadableString() const {
  52   std::ostringstream s;
  53   s << "format: " << format() << " channel_layout: " << channel_layout()
  54     << " channels: " << channels() << " sample_rate: " << sample_rate()
  55     << " bits_per_sample: " << bits_per_sample()
  56     << " frames_per_buffer: " << frames_per_buffer()
  57     << " effects: " << effects();
  58   return s.str();
  59 }
  60
  61 int AudioParameters::GetBytesPerBuffer() const {
  62   return frames_per_buffer_ * GetBytesPerFrame();
  63 }
  64
  65 int AudioParameters::GetBytesPerSecond() const {
  66   return sample_rate_ * GetBytesPerFrame();
  67 }
  68
  69 int AudioParameters::GetBytesPerFrame() const {
  70   return channels_ * bits_per_sample_ / 8;
  71 }
  72
  73 base::TimeDelta AudioParameters::GetBufferDuration() const {
  74   return base::TimeDelta::FromMicroseconds(static_cast<int64>(
  75       frames_per_buffer_ * base::Time::kMicrosecondsPerSecond /
  76       static_cast<float>(sample_rate_)));
  77 }
  78
  79 bool AudioParameters::Equals(const AudioParameters& other) const {
  80   return format_ == other.format() &&
  81          sample_rate_ == other.sample_rate() &&
  82          channel_layout_ == other.channel_layout() &&
  83          channels_ == other.channels() &&
  84          bits_per_sample_ == other.bits_per_sample() &&
  85          frames_per_buffer_ == other.frames_per_buffer() &&
  86          effects_ == other.effects();
  87 }
  88
  89 }  // namespace media