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media / audio / cras / audio_manager_cras.cc [blame]
// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "media/audio/cras/audio_manager_cras.h"
#include <stddef.h>
#include <algorithm>
#include <map>
#include <utility>
#include "base/check_op.h"
#include "base/command_line.h"
#include "base/environment.h"
#include "base/functional/bind.h"
#include "base/metrics/field_trial_params.h"
#include "base/nix/xdg_util.h"
#include "base/strings/string_number_conversions.h"
#include "base/system/sys_info.h"
#include "base/task/single_thread_task_runner.h"
#include "media/audio/audio_device_description.h"
#include "media/audio/cras/cras_input.h"
#include "media/audio/cras/cras_unified.h"
#include "media/audio/cras/cras_util.h"
#include "media/base/channel_layout.h"
#include "media/base/limits.h"
#include "media/base/localized_strings.h"
#include "media/base/media_switches.h"
namespace media {
namespace {
// Default sample rate for input and output streams.
const int kDefaultSampleRate = 48000;
// Default input buffer size.
const int kDefaultInputBufferSize = 1024;
// Default output buffer size.
const int kDefaultOutputBufferSize = 512;
} // namespace
bool AudioManagerCras::HasAudioOutputDevices() {
return true;
}
bool AudioManagerCras::HasAudioInputDevices() {
return !cras_util_->CrasGetAudioDevices(DeviceType::kInput).empty();
}
AudioManagerCras::AudioManagerCras(std::unique_ptr<AudioThread> audio_thread,
AudioLogFactory* audio_log_factory)
: AudioManagerCrasBase(std::move(audio_thread), audio_log_factory),
cras_util_(std::make_unique<CrasUtil>()),
main_task_runner_(base::SingleThreadTaskRunner::GetCurrentDefault()),
weak_ptr_factory_(this) {
weak_this_ = weak_ptr_factory_.GetWeakPtr();
}
AudioManagerCras::~AudioManagerCras() = default;
void AudioManagerCras::GetAudioInputDeviceNames(
AudioDeviceNames* device_names) {
for (const auto& device :
cras_util_->CrasGetAudioDevices(DeviceType::kInput)) {
device_names->emplace_back(device.name, base::NumberToString(device.id));
}
if (!device_names->empty()) {
device_names->push_front(AudioDeviceName::CreateDefault());
}
}
void AudioManagerCras::GetAudioOutputDeviceNames(
AudioDeviceNames* device_names) {
for (const auto& device :
cras_util_->CrasGetAudioDevices(DeviceType::kOutput)) {
device_names->emplace_back(device.name, base::NumberToString(device.id));
}
if (!device_names->empty()) {
device_names->push_front(AudioDeviceName::CreateDefault());
}
}
// Checks if a system AEC with a specific group ID is flagged to be deactivated
// by the field trial.
bool IsSystemAecDeactivated(int aec_group_id) {
return base::GetFieldTrialParamByFeatureAsBool(
media::kCrOSSystemAECDeactivatedGroups,
base::NumberToString(aec_group_id), false);
}
// Checks if the board with `aec_group_id` is flagged by the field trial to not
// allow using DSP-based AEC effect.
bool IsDspBasedAecDeactivated(int aec_group_id) {
return base::GetFieldTrialParamByFeatureAsBool(
media::kCrOSDspBasedAecDeactivatedGroups,
base::NumberToString(aec_group_id), false) ||
!base::FeatureList::IsEnabled(media::kCrOSDspBasedAecAllowed);
}
// Checks if the board with `aec_group_id` is flagged by the field trial to not
// allow using DSP-based NS effect.
bool IsDspBasedNsDeactivated(int aec_group_id) {
return base::GetFieldTrialParamByFeatureAsBool(
media::kCrOSDspBasedNsDeactivatedGroups,
base::NumberToString(aec_group_id), false) ||
!base::FeatureList::IsEnabled(media::kCrOSDspBasedNsAllowed);
}
// Checks if the board with `aec_group_id` is flagged by the field trial to not
// allow using DSP-based AGC effect.
bool IsDspBasedAgcDeactivated(int aec_group_id) {
return base::GetFieldTrialParamByFeatureAsBool(
media::kCrOSDspBasedAgcDeactivatedGroups,
base::NumberToString(aec_group_id), false) ||
!base::FeatureList::IsEnabled(media::kCrOSDspBasedAgcAllowed);
}
// Specifies which DSP-based effects are allowed based on media constraints and
// any finch field trials.
void SetAllowedDspBasedEffects(int aec_group_id, AudioParameters& params) {
int effects = params.effects();
// Allow AEC to be applied by CRAS on DSP if the AEC is active in CRAS and if
// using the AEC on DSP has not been deactivated by any field trials.
if ((effects & AudioParameters::ECHO_CANCELLER) &&
!IsDspBasedAecDeactivated(aec_group_id)) {
effects = effects | AudioParameters::ALLOW_DSP_ECHO_CANCELLER;
} else {
effects = effects & ~AudioParameters::ALLOW_DSP_ECHO_CANCELLER;
}
// Allow NS to be applied by CRAS on DSP if the NS is active in CRAS and if
// using the NS on DSP has not been deactivated by any field trials.
if ((effects & AudioParameters::NOISE_SUPPRESSION) &&
!IsDspBasedNsDeactivated(aec_group_id)) {
effects = effects | AudioParameters::ALLOW_DSP_NOISE_SUPPRESSION;
} else {
effects = effects & ~AudioParameters::ALLOW_DSP_NOISE_SUPPRESSION;
}
// Allow AGC to be applied by CRAS on DSP if the AGC is active in CRAS and if
// using the AGC on DSP has not been deactivated by any field trials.
if ((effects & AudioParameters::AUTOMATIC_GAIN_CONTROL) &&
!IsDspBasedAgcDeactivated(aec_group_id)) {
effects = effects | AudioParameters::ALLOW_DSP_AUTOMATIC_GAIN_CONTROL;
} else {
effects = effects & ~AudioParameters::ALLOW_DSP_AUTOMATIC_GAIN_CONTROL;
}
params.set_effects(effects);
}
// Collects flags values for whether, and in what way, the AEC, NS or AGC
// effects should be enforced in spite of them not being flagged as supported by
// the board.
void RetrieveSystemEffectFeatures(bool& enforce_system_aec,
bool& enforce_system_ns,
bool& enforce_system_agc,
bool& tuned_system_aec_allowed) {
const bool enforce_system_aec_ns_agc_feature =
base::FeatureList::IsEnabled(media::kCrOSEnforceSystemAecNsAgc);
const bool enforce_system_aec_ns_feature =
base::FeatureList::IsEnabled(media::kCrOSEnforceSystemAecNs);
const bool enforce_system_aec_agc_feature =
base::FeatureList::IsEnabled(media::kCrOSEnforceSystemAecAgc);
const bool enforce_system_aec_feature =
base::FeatureList::IsEnabled(media::kCrOSEnforceSystemAec);
const bool enforce_system_aec_by_policy =
base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kSystemAecEnabled);
enforce_system_aec =
enforce_system_aec_feature || enforce_system_aec_ns_agc_feature ||
enforce_system_aec_ns_feature || enforce_system_aec_agc_feature ||
enforce_system_aec_by_policy;
enforce_system_ns =
enforce_system_aec_ns_agc_feature || enforce_system_aec_ns_feature;
enforce_system_agc =
enforce_system_aec_ns_agc_feature || enforce_system_aec_agc_feature;
tuned_system_aec_allowed =
base::FeatureList::IsEnabled(media::kCrOSSystemAEC);
}
AudioParameters AudioManagerCras::GetStreamParametersForSystem(
int user_buffer_size) {
AudioParameters params(
AudioParameters::AUDIO_PCM_LOW_LATENCY, ChannelLayoutConfig::Stereo(),
kDefaultSampleRate, user_buffer_size,
AudioParameters::HardwareCapabilities(limits::kMinAudioBufferSize,
limits::kMaxAudioBufferSize));
bool enforce_system_aec;
bool enforce_system_ns;
bool enforce_system_agc;
bool tuned_system_aec_allowed;
RetrieveSystemEffectFeatures(enforce_system_aec, enforce_system_ns,
enforce_system_agc, tuned_system_aec_allowed);
// Rephrase the field aec_supported to properly reflect its meaning in this
// context (since it currently signals whether an CrAS APM with tuned settings
// is available).
const bool tuned_system_apm_available = cras_util_->CrasGetAecSupported();
// Don't use the system AEC if it is deactivated for this group ID. Also never
// activate NS nor AGC for this board if the AEC is not activated, since this
// will cause issues for the Browser AEC.
bool use_system_aec =
(tuned_system_apm_available && tuned_system_aec_allowed) ||
enforce_system_aec;
bool system_ns_supported = cras_util_->CrasGetNsSupported();
bool system_agc_supported = cras_util_->CrasGetAgcSupported();
int aec_group_id = cras_util_->CrasGetAecGroupId();
if (!use_system_aec || IsSystemAecDeactivated(aec_group_id)) {
SetAllowedDspBasedEffects(aec_group_id, params);
return params;
}
// Activation of the system AEC.
params.set_effects(params.effects() | AudioParameters::ECHO_CANCELLER);
// Don't use system NS or AGC if the AEC has board-specific tunings.
if (!tuned_system_apm_available) {
// Activation of the system NS.
if (system_ns_supported || enforce_system_ns) {
params.set_effects(params.effects() | AudioParameters::NOISE_SUPPRESSION);
}
// Activation of the system AGC.
if (system_agc_supported || enforce_system_agc) {
params.set_effects(params.effects() |
AudioParameters::AUTOMATIC_GAIN_CONTROL);
}
}
if (base::FeatureList::IsEnabled(media::kCrOSSystemVoiceIsolationOption)) {
if (cras_util_->CrasGetVoiceIsolationSupported()) {
params.set_effects(params.effects() |
AudioParameters::VOICE_ISOLATION_SUPPORTED);
}
}
SetAllowedDspBasedEffects(aec_group_id, params);
return params;
}
AudioParameters AudioManagerCras::GetInputStreamParameters(
const std::string& device_id) {
DCHECK(GetTaskRunner()->BelongsToCurrentThread());
int user_buffer_size = GetUserBufferSize();
user_buffer_size =
user_buffer_size ? user_buffer_size : kDefaultInputBufferSize;
return GetStreamParametersForSystem(user_buffer_size);
}
std::string AudioManagerCras::GetDefaultInputDeviceID() {
DCHECK(GetTaskRunner()->BelongsToCurrentThread());
return base::NumberToString(GetPrimaryActiveInputNode());
}
std::string AudioManagerCras::GetDefaultOutputDeviceID() {
DCHECK(GetTaskRunner()->BelongsToCurrentThread());
return base::NumberToString(GetPrimaryActiveOutputNode());
}
std::string AudioManagerCras::GetGroupIDInput(const std::string& device_id) {
for (const auto& device :
cras_util_->CrasGetAudioDevices(DeviceType::kInput)) {
if (base::NumberToString(device.id) == device_id ||
(AudioDeviceDescription::IsDefaultDevice(device_id) && device.active)) {
return device.dev_name;
}
}
return "";
}
std::string AudioManagerCras::GetGroupIDOutput(const std::string& device_id) {
for (const auto& device :
cras_util_->CrasGetAudioDevices(DeviceType::kOutput)) {
if (base::NumberToString(device.id) == device_id ||
(AudioDeviceDescription::IsDefaultDevice(device_id) && device.active)) {
return device.dev_name;
}
}
return "";
}
std::string AudioManagerCras::GetAssociatedOutputDeviceID(
const std::string& input_device_id) {
if (AudioDeviceDescription::IsDefaultDevice(input_device_id)) {
// Note: the default input should not be associated to any output, as this
// may lead to accidental uses of a pinned stream.
return "";
}
std::string device_name = GetGroupIDInput(input_device_id);
if (device_name.empty()) {
return "";
}
// Now search for an output device with the same device name.
for (const auto& device :
cras_util_->CrasGetAudioDevices(DeviceType::kOutput)) {
if (device.dev_name == device_name) {
return base::NumberToString(device.id);
}
}
return "";
}
AudioParameters AudioManagerCras::GetPreferredOutputStreamParameters(
const std::string& output_device_id,
const AudioParameters& input_params) {
DCHECK(GetTaskRunner()->BelongsToCurrentThread());
ChannelLayoutConfig channel_layout_config = ChannelLayoutConfig::Stereo();
int sample_rate = kDefaultSampleRate;
int buffer_size = GetUserBufferSize();
if (input_params.IsValid()) {
channel_layout_config = input_params.channel_layout_config();
sample_rate = input_params.sample_rate();
if (!buffer_size) { // Not user-provided.
buffer_size =
std::min(static_cast<int>(limits::kMaxAudioBufferSize),
std::max(static_cast<int>(limits::kMinAudioBufferSize),
input_params.frames_per_buffer()));
}
return AudioParameters(
AudioParameters::AUDIO_PCM_LOW_LATENCY, channel_layout_config,
sample_rate, buffer_size,
AudioParameters::HardwareCapabilities(limits::kMinAudioBufferSize,
limits::kMaxAudioBufferSize));
}
// Get max supported channels from |output_device_id| or the primary active
// one if |output_device_id| is the default device.
uint64_t preferred_device_id;
if (AudioDeviceDescription::IsDefaultDevice(output_device_id)) {
preferred_device_id = GetPrimaryActiveOutputNode();
} else {
if (!base::StringToUint64(output_device_id, &preferred_device_id)) {
preferred_device_id = 0; // 0 represents invalid |output_device_id|.
}
}
for (const auto& device :
cras_util_->CrasGetAudioDevices(DeviceType::kOutput)) {
if (device.id == preferred_device_id) {
channel_layout_config = ChannelLayoutConfig::Guess(
static_cast<int>(device.max_supported_channels));
// Fall-back to old fashion: always fixed to STEREO layout.
if (channel_layout_config.channel_layout() ==
CHANNEL_LAYOUT_UNSUPPORTED) {
channel_layout_config = ChannelLayoutConfig::Stereo();
}
break;
}
}
if (!buffer_size) { // Not user-provided.
buffer_size = cras_util_->CrasGetDefaultOutputBufferSize();
}
if (buffer_size <= 0) {
buffer_size = kDefaultOutputBufferSize;
}
return AudioParameters(
AudioParameters::AUDIO_PCM_LOW_LATENCY, channel_layout_config,
sample_rate, buffer_size,
AudioParameters::HardwareCapabilities(limits::kMinAudioBufferSize,
limits::kMaxAudioBufferSize));
}
uint64_t AudioManagerCras::GetPrimaryActiveInputNode() {
for (const auto& device :
cras_util_->CrasGetAudioDevices(DeviceType::kInput)) {
if (device.active) {
return device.id;
}
}
return 0;
}
uint64_t AudioManagerCras::GetPrimaryActiveOutputNode() {
for (const auto& device :
cras_util_->CrasGetAudioDevices(DeviceType::kOutput)) {
if (device.active) {
return device.id;
}
}
return 0;
}
bool AudioManagerCras::IsDefault(const std::string& device_id, bool is_input) {
return AudioDeviceDescription::IsDefaultDevice(device_id);
}
enum CRAS_CLIENT_TYPE AudioManagerCras::GetClientType() {
#if BUILDFLAG(IS_CHROMEOS_ASH)
return CRAS_CLIENT_TYPE_CHROME;
#else
return CRAS_CLIENT_TYPE_LACROS;
#endif
}
} // namespace media