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media / audio / win / audio_manager_win.cc [blame]
// Copyright 2012 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/win/audio_manager_win.h"
#include <objbase.h>
#include <initguid.h>
#include <windows.h>
#include <mmsystem.h>
#include <setupapi.h>
#include <stddef.h>
#include <utility>
#include "base/command_line.h"
#include "base/functional/bind.h"
#include "base/functional/callback_helpers.h"
#include "base/strings/string_number_conversions.h"
#include "base/task/bind_post_task.h"
#include "base/win/windows_version.h"
#include "media/audio/audio_device_description.h"
#include "media/audio/audio_io.h"
#include "media/audio/win/audio_device_listener_win.h"
#include "media/audio/win/audio_low_latency_input_win.h"
#include "media/audio/win/audio_low_latency_output_win.h"
#include "media/audio/win/core_audio_util_win.h"
#include "media/audio/win/device_enumeration_win.h"
#include "media/audio/win/waveout_output_win.h"
#include "media/base/audio_parameters.h"
#include "media/base/channel_layout.h"
#include "media/base/limits.h"
#include "media/base/media_switches.h"
// The following are defined in various DDK headers, and we (re)define them here
// to avoid adding the DDK as a chrome dependency.
#define DRV_QUERYDEVICEINTERFACE 0x80c
#define DRVM_MAPPER_PREFERRED_GET 0x2015
#define DRV_QUERYDEVICEINTERFACESIZE 0x80d
DEFINE_GUID(AM_KSCATEGORY_AUDIO,
0x6994ad04,
0x93ef,
0x11d0,
0xa3,
0xcc,
0x00,
0xa0,
0xc9,
0x22,
0x31,
0x96);
namespace media {
// Maximum number of output streams that can be open simultaneously.
constexpr int kMaxOutputStreams = 50;
// Up to 8 channels can be passed to the driver. This should work, given the
// right drivers, but graceful error handling is needed.
constexpr int kWinMaxChannels = 8;
// Buffer size to use for input and output stream when a proper size can't be
// determined from the system
constexpr int kFallbackBufferSize = 2048;
namespace {
int NumberOfWaveOutBuffers() {
// Use the user provided buffer count if provided.
int buffers = 0;
std::string buffers_str(
base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
switches::kWaveOutBuffers));
if (base::StringToInt(buffers_str, &buffers) && buffers > 0) {
return buffers;
}
return 3;
}
} // namespace
AudioManagerWin::AudioManagerWin(std::unique_ptr<AudioThread> audio_thread,
AudioLogFactory* audio_log_factory)
: AudioManagerBase(std::move(audio_thread), audio_log_factory) {
// |CoreAudioUtil::IsSupported()| uses static variables to avoid doing
// multiple initializations. This is however not thread safe.
// So, here we call it explicitly before we kick off the audio thread
// or do any other work.
CoreAudioUtil::IsSupported();
SetMaxOutputStreamsAllowed(kMaxOutputStreams);
// WARNING: This may be executed on the UI loop, do not add any code here
// which loads libraries or attempts to call out into the OS. Instead add
// such code to the InitializeOnAudioThread() method below.
// In case we are already on the audio thread (i.e. when running out of
// process audio), don't post.
if (GetTaskRunner()->BelongsToCurrentThread()) {
this->InitializeOnAudioThread();
return;
}
// Task must be posted last to avoid races from handing out "this" to the
// audio thread. Unretained is safe since we join the audio thread before
// destructing |this|.
GetTaskRunner()->PostTask(
FROM_HERE, base::BindOnce(&AudioManagerWin::InitializeOnAudioThread,
base::Unretained(this)));
}
AudioManagerWin::~AudioManagerWin() = default;
void AudioManagerWin::ShutdownOnAudioThread() {
// Prevent pending callbacks from `output_device_listener_` from being run.
// TODO(crbug.com/40066532): Remove this call when kAudioServiceOutOfProcess
// is removed on Windows; `weak_factory_on_audio_thread_` will be guaranteed
// to be destroyed/invalidated on the right thread then.
weak_factory_on_audio_thread_.InvalidateWeakPtrs();
AudioManagerBase::ShutdownOnAudioThread();
// Destroy AudioDeviceListenerWin instance on the audio thread because it
// expects to be constructed and destroyed on the same thread.
output_device_listener_.reset();
}
bool AudioManagerWin::HasAudioOutputDevices() {
if (CoreAudioUtil::IsSupported())
return CoreAudioUtil::NumberOfActiveDevices(eRender) > 0;
return (::waveOutGetNumDevs() != 0);
}
bool AudioManagerWin::HasAudioInputDevices() {
if (CoreAudioUtil::IsSupported())
return CoreAudioUtil::NumberOfActiveDevices(eCapture) > 0;
return (::waveInGetNumDevs() != 0);
}
void AudioManagerWin::InitializeOnAudioThread() {
DCHECK(GetTaskRunner()->BelongsToCurrentThread());
// Initialize should only be called once.
CHECK(!output_device_listener_);
// Create a WeakPtr bound to the Audio thread, which will be invalidated
// in ShutdownOnAudioThread().
weak_this_on_audio_thread_ = weak_factory_on_audio_thread_.GetWeakPtr();
// AudioDeviceListenerWin must be initialized on a COM thread.
// Despite `this` owning `output_device_listener_`, we need to bind the
// callback to a WeakPtr: NotifyAllOutputDeviceChangeListeners() will be
// posted to the audio thread instead of being run synchronously, since we use
// BindPostTaskToCurrentDefault().
output_device_listener_ = std::make_unique<AudioDeviceListenerWin>(
base::BindPostTaskToCurrentDefault(base::BindRepeating(
&AudioManagerWin::NotifyAllOutputDeviceChangeListeners,
weak_this_on_audio_thread_)));
}
void AudioManagerWin::GetAudioDeviceNamesImpl(bool input,
AudioDeviceNames* device_names) {
DCHECK(device_names->empty());
// Enumerate all active audio-endpoint capture devices.
if (input)
GetInputDeviceNamesWin(device_names);
else
GetOutputDeviceNamesWin(device_names);
if (!device_names->empty()) {
device_names->push_front(AudioDeviceName::CreateCommunications());
// Always add default device parameters as first element.
device_names->push_front(AudioDeviceName::CreateDefault());
}
}
void AudioManagerWin::GetAudioInputDeviceNames(AudioDeviceNames* device_names) {
GetAudioDeviceNamesImpl(true, device_names);
}
void AudioManagerWin::GetAudioOutputDeviceNames(
AudioDeviceNames* device_names) {
GetAudioDeviceNamesImpl(false, device_names);
}
AudioParameters AudioManagerWin::GetInputStreamParameters(
const std::string& device_id) {
AudioParameters parameters;
HRESULT hr =
CoreAudioUtil::GetPreferredAudioParameters(device_id, false, ¶meters);
if (FAILED(hr) || !parameters.IsValid()) {
LOG(WARNING) << "Unable to get preferred audio params for " << device_id
<< " 0x" << std::hex << hr;
// TODO(tommi): We appear to have callers to GetInputStreamParameters that
// rely on getting valid audio parameters returned for an invalid or
// unavailable device. We should track down those code paths (it is likely
// that they actually don't need a real device but depend on the audio
// code path somehow for a configuration - e.g. tab capture).
parameters = AudioParameters(AudioParameters::AUDIO_PCM_LINEAR,
ChannelLayoutConfig::Stereo(), 48000,
kFallbackBufferSize);
}
int user_buffer_size = GetUserBufferSize();
if (user_buffer_size)
parameters.set_frames_per_buffer(user_buffer_size);
return parameters;
}
std::string AudioManagerWin::GetAssociatedOutputDeviceID(
const std::string& input_device_id) {
return CoreAudioUtil::GetMatchingOutputDeviceID(input_device_id);
}
const char* AudioManagerWin::GetName() {
return "Windows";
}
// Factory for the implementations of AudioOutputStream for AUDIO_PCM_LINEAR
// mode.
// - PCMWaveOutAudioOutputStream: Based on the waveOut API.
AudioOutputStream* AudioManagerWin::MakeLinearOutputStream(
const AudioParameters& params,
const LogCallback& log_callback) {
DCHECK_EQ(AudioParameters::AUDIO_PCM_LINEAR, params.format());
if (params.channels() > kWinMaxChannels)
return nullptr;
return new PCMWaveOutAudioOutputStream(this, params, NumberOfWaveOutBuffers(),
WAVE_MAPPER);
}
AudioOutputStream* AudioManagerWin::MakeBitstreamOutputStream(
const AudioParameters& params,
const std::string& device_id,
const LogCallback& log_callback) {
#if BUILDFLAG(ENABLE_PLATFORM_DTS_AUDIO)
return MakeLowLatencyOutputStream(params, device_id, log_callback);
#else // BUILDFLAG(ENABLE_PLATFORM_DTS_AUDIO)
return nullptr;
#endif // BUILDFLAG(ENABLE_PLATFORM_DTS_AUDIO)
}
// Factory for the implementations of AudioOutputStream for
// AUDIO_PCM_LOW_LATENCY mode. Two implementations should suffice most
// windows user's needs.
// - PCMWaveOutAudioOutputStream: Based on the waveOut API.
// - WASAPIAudioOutputStream: Based on Core Audio (WASAPI) API.
AudioOutputStream* AudioManagerWin::MakeLowLatencyOutputStream(
const AudioParameters& params,
const std::string& device_id,
const LogCallback& log_callback) {
#if BUILDFLAG(ENABLE_PLATFORM_DTS_AUDIO)
DCHECK(params.format() == AudioParameters::AUDIO_BITSTREAM_DTS ||
params.format() == AudioParameters::AUDIO_PCM_LOW_LATENCY)
<< params.format();
#else
DCHECK_EQ(params.format(), AudioParameters::AUDIO_PCM_LOW_LATENCY);
#endif
if (params.channels() > kWinMaxChannels)
return nullptr;
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kForceWaveAudio)) {
DLOG(WARNING) << "Forcing usage of Windows WaveXxx APIs";
return nullptr;
}
// Pass an empty string to indicate that we want the default device
// since we consistently only check for an empty string in
// WASAPIAudioOutputStream.
bool communications =
device_id == AudioDeviceDescription::kCommunicationsDeviceId;
return new WASAPIAudioOutputStream(
this,
communications || device_id == AudioDeviceDescription::kDefaultDeviceId
? std::string()
: device_id,
params, communications ? eCommunications : eConsole, log_callback);
}
// Factory for the implementations of AudioInputStream for AUDIO_PCM_LINEAR
// mode.
AudioInputStream* AudioManagerWin::MakeLinearInputStream(
const AudioParameters& params,
const std::string& device_id,
const LogCallback& log_callback) {
DCHECK_EQ(AudioParameters::AUDIO_PCM_LINEAR, params.format());
return MakeLowLatencyInputStream(params, device_id, log_callback);
}
// Factory for the implementations of AudioInputStream for
// AUDIO_PCM_LOW_LATENCY mode.
AudioInputStream* AudioManagerWin::MakeLowLatencyInputStream(
const AudioParameters& params,
const std::string& device_id,
const LogCallback& log_callback) {
// Used for both AUDIO_PCM_LOW_LATENCY and AUDIO_PCM_LINEAR.
return new WASAPIAudioInputStream(this, params, device_id, log_callback);
}
std::string AudioManagerWin::GetDefaultInputDeviceID() {
return CoreAudioUtil::GetDefaultInputDeviceID();
}
std::string AudioManagerWin::GetDefaultOutputDeviceID() {
return CoreAudioUtil::GetDefaultOutputDeviceID();
}
std::string AudioManagerWin::GetCommunicationsInputDeviceID() {
return CoreAudioUtil::GetCommunicationsInputDeviceID();
}
std::string AudioManagerWin::GetCommunicationsOutputDeviceID() {
return CoreAudioUtil::GetCommunicationsOutputDeviceID();
}
AudioParameters AudioManagerWin::GetPreferredOutputStreamParameters(
const std::string& output_device_id,
const AudioParameters& input_params) {
const base::CommandLine* cmd_line = base::CommandLine::ForCurrentProcess();
ChannelLayoutConfig channel_layout_config = ChannelLayoutConfig::Stereo();
int sample_rate = 48000;
int buffer_size = kFallbackBufferSize;
int effects = AudioParameters::NO_EFFECTS;
int min_buffer_size = 0;
int max_buffer_size = 0;
int default_buffer_size = 0;
bool attempt_audio_offload = CoreAudioUtil::IsAudioOffloadSupported(nullptr);
if (cmd_line->HasSwitch(switches::kEnableExclusiveAudio)) {
// TODO(rtoy): tune these values for best possible WebAudio
// performance. WebRTC works well at 48kHz and a buffer size of 480
// samples will be used for this case. Note that exclusive mode is
// experimental. This sample rate will be combined with a buffer size of
// 256 samples, which corresponds to an output delay of ~5.33ms.
sample_rate = 48000;
buffer_size = 256;
if (input_params.IsValid())
channel_layout_config = input_params.channel_layout_config();
} else {
AudioParameters params;
HRESULT hr = CoreAudioUtil::GetPreferredAudioParameters(
output_device_id.empty() ? GetDefaultOutputDeviceID()
: output_device_id,
true, ¶ms, attempt_audio_offload);
if (FAILED(hr)) {
// This can happen when CoreAudio isn't supported or available
// (e.g. certain installations of Windows Server 2008 R2).
// Instead of returning the input_params, we'll return invalid
// AudioParameters to make sure that an attempt to create this output
// stream, won't succeed. This behavior is also consistent with
// GetInputStreamParameters.
DLOG(ERROR) << "GetPreferredAudioParameters failed: " << std::hex << hr;
return AudioParameters();
}
DVLOG(1) << params.AsHumanReadableString();
DCHECK(params.IsValid());
channel_layout_config = params.channel_layout_config();
buffer_size = params.frames_per_buffer();
sample_rate = params.sample_rate();
effects = params.effects();
AudioParameters::HardwareCapabilities hardware_capabilities =
params.hardware_capabilities().value_or(
AudioParameters::HardwareCapabilities());
min_buffer_size = hardware_capabilities.min_frames_per_buffer;
max_buffer_size = hardware_capabilities.max_frames_per_buffer;
default_buffer_size = hardware_capabilities.default_frames_per_buffer;
}
if (input_params.IsValid()) {
// If the user has enabled checking supported channel layouts or we don't
// have a valid channel layout yet, try to use the input layout. See bugs
// http://crbug.com/259165 and http://crbug.com/311906 for more details.
if (cmd_line->HasSwitch(switches::kTrySupportedChannelLayouts) ||
channel_layout_config.channel_layout() == CHANNEL_LAYOUT_UNSUPPORTED) {
// Check if it is possible to open up at the specified input channel
// layout but avoid checking if the specified layout is the same as the
// hardware (preferred) layout. We do this extra check to avoid the
// CoreAudioUtil::IsChannelLayoutSupported() overhead in most cases.
if (input_params.channel_layout() !=
channel_layout_config.channel_layout()) {
// TODO(henrika): Internally, IsChannelLayoutSupported does many of the
// operations that have already been done such as opening up a client
// and fetching the WAVEFORMATPCMEX format. Ideally we should only do
// that once. Then here, we can check the layout from the data we
// already hold.
if (CoreAudioUtil::IsChannelLayoutSupported(
output_device_id, eRender, eConsole,
input_params.channel_layout())) {
// Open up using the same channel layout as the source if it is
// supported by the hardware.
channel_layout_config = input_params.channel_layout_config();
DVLOG(1) << "Hardware channel layout is not used; using same layout"
<< " as the source instead ("
<< channel_layout_config.channel_layout() << ")";
}
}
}
effects |= input_params.effects();
// Allow non-default buffer sizes if we have a valid min and max.
if (min_buffer_size > 0 && max_buffer_size > 0) {
buffer_size =
std::min(max_buffer_size,
std::max(input_params.frames_per_buffer(), min_buffer_size));
}
}
int user_buffer_size = GetUserBufferSize();
if (user_buffer_size)
buffer_size = user_buffer_size;
AudioParameters::HardwareCapabilities hardware_capabilities(
min_buffer_size, max_buffer_size, default_buffer_size,
attempt_audio_offload);
#if BUILDFLAG(ENABLE_PASSTHROUGH_AUDIO_CODECS)
hardware_capabilities.bitstream_formats = 0;
hardware_capabilities.require_encapsulation = false;
if (WASAPIAudioOutputStream::GetShareMode() == AUDCLNT_SHAREMODE_EXCLUSIVE) {
hardware_capabilities.bitstream_formats = GetPassthroughAudioFormats();
hardware_capabilities.require_encapsulation = true;
}
#endif // BUILDFLAG(ENABLE_PASSTHROUGH_AUDIO_CODECS)
AudioParameters params(AudioParameters::AUDIO_PCM_LOW_LATENCY,
channel_layout_config, sample_rate, buffer_size,
hardware_capabilities);
params.set_effects(effects);
DCHECK(params.IsValid());
return params;
}
// static
std::unique_ptr<AudioManager> CreateAudioManager(
std::unique_ptr<AudioThread> audio_thread,
AudioLogFactory* audio_log_factory) {
return std::make_unique<AudioManagerWin>(std::move(audio_thread),
audio_log_factory);
}
} // namespace media