Added experimental XAudio2 audio player

Removed downsampling in FFMS2 and CreateConvertAudioProvider, to ensure we can get the original audio channels and data.

Fix Aegisub/Aegisub#160

CMakeLists.txt

@@ -572,9 +572,9 @@ if(WITH_CSRI)
 endif()
 
 if(WIN32)
-    target_compile_definitions(Aegisub PRIVATE "WITH_DIRECTSOUND")
+    target_compile_definitions(Aegisub PRIVATE "WITH_DIRECTSOUND" "WITH_XAUDIO2")
     target_link_libraries(Aegisub dsound)
-    target_sources(Aegisub PRIVATE src/audio_player_dsound.cpp src/audio_player_dsound2.cpp)
+    target_sources(Aegisub PRIVATE src/audio_player_dsound.cpp src/audio_player_dsound2.cpp src/audio_player_xaudio2.cpp)
     set(WITH_DIRECTSOUND ON)
 else()
     set(WITH_DIRECTSOUND OFF)

libaegisub/audio/provider_convert.cpp

@@ -87,13 +87,14 @@ std::unique_ptr<AudioProvider> CreateConvertAudioProvider(std::unique_ptr<AudioP
 	if (provider->GetChannels() != 1)
 		LOG_D("audio_provider") << "Downmixing to mono from " << provider->GetChannels() << " channels";
 
-	provider = agi::make_unique<ConvertAudioProvider>(std::move(provider));
-
 	// Some players don't like low sample rate audio
+	if (provider->GetSampleRate() < 32000) {
+		provider = agi::make_unique<ConvertAudioProvider>(std::move(provider));
 		while (provider->GetSampleRate() < 32000) {
 			LOG_D("audio_provider") << "Doubling sample rate";
 			provider = agi::make_unique<SampleDoublingAudioProvider>(std::move(provider));
 		}
+	}
 
 	return provider;
 }

src/audio_player.cpp

@@ -47,6 +47,9 @@ std::unique_ptr<AudioPlayer> CreateAlsaPlayer(agi::AudioProvider *providers, wxW
 std::unique_ptr<AudioPlayer> CreateDirectSoundPlayer(agi::AudioProvider *providers, wxWindow *window);
 std::unique_ptr<AudioPlayer> CreateDirectSound2Player(agi::AudioProvider *providers, wxWindow *window);
 #endif
+#ifdef WITH_XAUDIO2
+std::unique_ptr<AudioPlayer> CreateXAudio2Player(agi::AudioProvider* providers, wxWindow* window);
+#endif
 #ifdef WITH_OPENAL
 std::unique_ptr<AudioPlayer> CreateOpenALPlayer(agi::AudioProvider *providers, wxWindow *window);
 #endif
@@ -75,6 +78,9 @@ namespace {
 		{"DirectSound-old", CreateDirectSoundPlayer, false},
 		{"DirectSound", CreateDirectSound2Player, false},
 #endif
+#ifdef WITH_XAUDIO2
+		{"XAudio2", CreateXAudio2Player, false},
+#endif
 #ifdef WITH_OPENAL
 		{"OpenAL", CreateOpenALPlayer, false},
 #endif

src/audio_player_xaudio2.cpp

@@ -0,0 +1,687 @@
+// Copyright (c) 2019, Qirui Wang
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+//   * Redistributions of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//   * Redistributions in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//   * Neither the name of the Aegisub Group nor the names of its contributors
+//     may be used to endorse or promote products derived from this software
+//     without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// Aegisub Project http://www.aegisub.org/
+
+#ifdef WITH_XAUDIO2
+#include "include/aegisub/audio_player.h"
+
+#include "options.h"
+
+#include <libaegisub/audio/provider.h>
+#include <libaegisub/scoped_ptr.h>
+#include <libaegisub/log.h>
+#include <libaegisub/make_unique.h>
+
+#include <xaudio2.h>
+
+namespace {
+class XAudio2Thread;
+
+/// @class XAudio2Player
+/// @brief XAudio2-based audio player
+///
+/// The core design idea is to have a playback thread that performs all playback operations, and use the player object as a proxy to send commands to the playback thread.
+class XAudio2Player final : public AudioPlayer {
+	/// The playback thread
+	std::unique_ptr<XAudio2Thread> thread;
+
+	/// Desired length in milliseconds to write ahead of the playback cursor
+	int WantedLatency;
+
+	/// Multiplier for WantedLatency to get total buffer length
+	int BufferLength;
+
+	/// @brief Tell whether playback thread is alive
+	/// @return True if there is a playback thread and it's ready
+	bool IsThreadAlive();
+
+public:
+	/// @brief Constructor
+	XAudio2Player(agi::AudioProvider* provider);
+	/// @brief Destructor
+	~XAudio2Player() = default;
+
+	/// @brief Start playback
+	/// @param start First audio frame to play
+	/// @param count Number of audio frames to play
+	void Play(int64_t start, int64_t count);
+
+	/// @brief Stop audio playback
+	/// @param timerToo Whether to also stop the playback update timer
+	void Stop();
+
+	/// @brief Tell whether playback is active
+	/// @return True if audio is playing back
+	bool IsPlaying();
+
+	/// @brief Get playback end position
+	/// @return Audio frame index
+	///
+	/// Returns 0 if playback is stopped or there is no playback thread
+	int64_t GetEndPosition();
+	/// @brief Get approximate playback position
+	/// @return Index of audio frame user is currently hearing
+	///
+	/// Returns 0 if playback is stopped or there is no playback thread
+	int64_t GetCurrentPosition();
+
+	/// @brief Change playback end position
+	/// @param pos New end position
+	void SetEndPosition(int64_t pos);
+
+	/// @brief Change playback volume
+	/// @param vol Amplification factor
+	void SetVolume(double vol);
+};
+
+/// @brief RAII support class to init and de-init the COM library
+struct COMInitialization {
+
+	/// Flag set if an inited COM library is managed
+	bool inited = false;
+
+	/// @brief Destructor, de-inits COM if it is inited
+	~COMInitialization() {
+		if (inited) CoUninitialize();
+	}
+
+	/// @brief Initialise the COM library as single-threaded apartment if isn't already inited by us
+	bool Init() {
+		if (!inited && SUCCEEDED(CoInitialize(nullptr)))
+			inited = true;
+		return inited;
+	}
+};
+
+struct ReleaseCOMObject {
+	void operator()(IUnknown* obj) {
+		if (obj) obj->Release();
+	}
+};
+
+/// @brief RAII wrapper around Win32 HANDLE type
+struct Win32KernelHandle final : public agi::scoped_holder<HANDLE, BOOL(__stdcall*)(HANDLE)> {
+	/// @brief Create with a managed handle
+	/// @param handle Win32 handle to manage
+	Win32KernelHandle(HANDLE handle = 0) :scoped_holder(handle, CloseHandle) {}
+
+	Win32KernelHandle& operator=(HANDLE new_handle) {
+		scoped_holder::operator=(new_handle);
+		return *this;
+	}
+};
+
+/// @class XAudio2Thread
+/// @brief Playback thread class for XAudio2Player
+///
+/// Not based on wxThread, but uses Win32 threads directly
+class XAudio2Thread :public IXAudio2VoiceCallback {
+	/// @brief Win32 thread entry point
+	/// @param parameter Pointer to our thread object
+	/// @return Thread return value, always 0 here
+	static unsigned int __stdcall ThreadProc(void* parameter);
+	/// @brief Thread entry point
+	void Run();
+
+	/// @brief Check for error state and throw exception if one occurred
+	void CheckError();
+
+	/// Win32 handle to the thread
+	Win32KernelHandle thread_handle;
+
+	/// Event object, world to thread, set to start playback
+	Win32KernelHandle event_start_playback;
+
+	/// Event object, world to thread, set to stop playback
+	Win32KernelHandle event_stop_playback;
+
+	/// Event object, world to thread, set if playback end time was updated
+	Win32KernelHandle event_update_end_time;
+
+	/// Event object, world to thread, set if the volume was changed
+	Win32KernelHandle event_set_volume;
+
+	/// Event object, world to thread, set if the thread should end as soon as possible
+	Win32KernelHandle event_buffer_end;
+
+	/// Event object, world to thread, set if the thread should end as soon as possible
+	Win32KernelHandle event_kill_self;
+
+	/// Event object, thread to world, set when the thread has entered its main loop
+	Win32KernelHandle thread_running;
+
+	/// Event object, thread to world, set when playback is ongoing
+	Win32KernelHandle is_playing;
+
+	/// Event object, thread to world, set if an error state has occurred (implies thread is dying)
+	Win32KernelHandle error_happened;
+
+	/// Statically allocated error message text describing reason for error_happened being set
+	const char* error_message = nullptr;
+
+	/// Playback volume, 1.0 is "unchanged"
+	double volume = 1.0;
+
+	/// Audio frame to start playback at
+	int64_t start_frame = 0;
+
+	/// Audio frame to end playback at
+	int64_t end_frame = 0;
+
+	/// Desired length in milliseconds to write ahead of the playback cursor
+	int wanted_latency;
+
+	/// Multiplier for WantedLatency to get total buffer length
+	int buffer_length;
+
+	/// System millisecond timestamp of last playback start, used to calculate playback position
+	ULONGLONG last_playback_restart;
+
+	/// Audio provider to take sample data from
+	agi::AudioProvider* provider;
+
+	/// Buffer occupied indicator
+	std::vector<bool> buffer_occupied;
+
+public:
+	/// @brief Constructor, creates and starts playback thread
+	/// @param provider       Audio provider to take sample data from
+	/// @param WantedLatency Desired length in milliseconds to write ahead of the playback cursor
+	/// @param BufferLength  Multiplier for WantedLatency to get total buffer length
+	XAudio2Thread(agi::AudioProvider* provider, int WantedLatency, int BufferLength);
+	/// @brief Destructor, waits for thread to have died
+	~XAudio2Thread();
+
+	// IXAudio2VoiceCallback
+	void OnVoiceProcessingPassStart(UINT32 BytesRequired) {}
+	void OnVoiceProcessingPassEnd() {}
+	void OnStreamEnd() {}
+	void OnBufferStart(void* pBufferContext) {}
+	void OnBufferEnd(void* pBufferContext) {
+		intptr_t i = reinterpret_cast<intptr_t>(pBufferContext);
+		buffer_occupied[i] = false;
+		SetEvent(event_buffer_end);
+	}
+	void OnLoopEnd(void* pBufferContext) {}
+	void OnVoiceError(void* pBufferContext, HRESULT Error) {}
+
+	/// @brief Start audio playback
+	/// @param start Audio frame to start playback at
+	/// @param count Number of audio frames to play
+	void Play(int64_t start, int64_t count);
+
+	/// @brief Stop audio playback
+	void Stop();
+
+	/// @brief Change audio playback end point
+	/// @param new_end_frame New last audio frame to play
+	///
+	/// Playback stops instantly if new_end_frame is before the current playback position
+	void SetEndFrame(int64_t new_end_frame);
+
+	/// @brief Change audio playback volume
+	/// @param new_volume New playback amplification factor, 1.0 is "unchanged"
+	void SetVolume(double new_volume);
+
+	/// @brief Tell whether audio playback is active
+	/// @return True if audio is being played back, false if it is not
+	bool IsPlaying();
+
+	/// @brief Get approximate current audio frame being heard by the user
+	/// @return Audio frame index
+	///
+	/// Returns 0 if not playing
+	int64_t GetCurrentFrame();
+
+	/// @brief Get audio playback end point
+	/// @return Audio frame index
+	int64_t GetEndFrame();
+
+	/// @brief Tell whether playback thread has died
+	/// @return True if thread is no longer running
+	bool IsDead();
+};
+
+unsigned int __stdcall XAudio2Thread::ThreadProc(void* parameter) {
+	static_cast<XAudio2Thread*>(parameter)->Run();
+	return 0;
+}
+
+/// Macro used to set error_message, error_happened and end the thread
+#define REPORT_ERROR(msg) \
+{ \
+	ResetEvent(is_playing); \
+	error_message = "XAudio2Thread: " msg; \
+	SetEvent(error_happened); \
+	return; \
+}
+
+void XAudio2Thread::Run() {
+	COMInitialization COM_library;
+	if (!COM_library.Init()) {
+		REPORT_ERROR("Could not initialise COM")
+	}
+	IXAudio2* pXAudio2;
+	IXAudio2SourceVoice* pSourceVoice;
+	HRESULT hr;
+	if (FAILED(hr = XAudio2Create(&pXAudio2, 0, XAUDIO2_DEFAULT_PROCESSOR))) {
+		REPORT_ERROR("Failed initializing XAudio2")
+	}
+	IXAudio2MasteringVoice* pMasterVoice = NULL;
+	if (FAILED(hr = pXAudio2->CreateMasteringVoice(&pMasterVoice))) {
+		REPORT_ERROR("Failed initializing XAudio2 MasteringVoice")
+	}
+
+#ifdef XAUDIO2_SAFE_FORMATS_ONLY
+	const bool original = provider->GetChannels() <= 2 && provider->AreSamplesFloat() ? provider->GetBytesPerSample() == 4 : provider->GetBytesPerSample() <= 2;
+#else
+	const bool original = true;
+#endif
+
+	// Describe the wave format
+	WAVEFORMATEX wfx;
+	wfx.nSamplesPerSec = provider->GetSampleRate();
+	wfx.cbSize = 0;
+	if (original) {
+		wfx.wFormatTag = provider->AreSamplesFloat() ? WAVE_FORMAT_IEEE_FLOAT : WAVE_FORMAT_PCM;
+		wfx.nChannels = provider->GetChannels();
+		wfx.wBitsPerSample = provider->GetBytesPerSample() * 8;
+	}
+	else {
+		wfx.wFormatTag = WAVE_FORMAT_PCM;
+		wfx.nChannels = 1;
+		wfx.wBitsPerSample = sizeof(int16_t) * 8;
+	}
+	wfx.nBlockAlign = wfx.nChannels * wfx.wBitsPerSample / 8;
+	wfx.nAvgBytesPerSec = wfx.nSamplesPerSec * wfx.nBlockAlign;
+
+	if (FAILED(hr = pXAudio2->CreateSourceVoice(&pSourceVoice, &wfx, 0, 2, this))) {
+		REPORT_ERROR("Failed initializing XAudio2 SourceVoice")
+	}
+
+	// Now we're ready to roll!
+	SetEvent(thread_running);
+	bool running = true;
+
+	HANDLE events_to_wait[] = {
+		event_start_playback,
+		event_stop_playback,
+		event_update_end_time,
+		event_set_volume,
+		event_buffer_end,
+		event_kill_self
+	};
+
+	int64_t next_input_frame = 0;
+	DWORD buffer_offset = 0;
+	bool playback_should_be_running = false;
+	int current_latency = wanted_latency;
+	const int wanted_frames = wanted_latency * wfx.nSamplesPerSec / 1000;
+	const DWORD wanted_latency_bytes = wanted_frames * wfx.nBlockAlign;
+	std::vector<std::vector<BYTE> > buff(buffer_length);
+	for (auto& i : buff)
+		i.resize(wanted_latency_bytes);
+
+	while (running) {
+		DWORD wait_result = WaitForMultipleObjects(sizeof(events_to_wait) / sizeof(HANDLE), events_to_wait, FALSE, INFINITE);
+
+		switch (wait_result) {
+		case WAIT_OBJECT_0 + 0:
+			// Start or restart playback
+			pSourceVoice->Stop();
+			pSourceVoice->FlushSourceBuffers();
+
+			next_input_frame = start_frame;
+			playback_should_be_running = true;
+			pSourceVoice->Start();
+			SetEvent(is_playing);
+			goto do_fill_buffer;
+
+		case WAIT_OBJECT_0 + 1:
+		stop_playback:
+			// Stop playing
+			ResetEvent(is_playing);
+			pSourceVoice->Stop();
+			pSourceVoice->FlushSourceBuffers();
+			playback_should_be_running = false;
+			break;
+
+		case WAIT_OBJECT_0 + 2:
+			// Set end frame
+			if (end_frame <= next_input_frame)
+				goto stop_playback;
+			goto do_fill_buffer;
+
+		case WAIT_OBJECT_0 + 3:
+			// Change volume
+			pSourceVoice->SetVolume(volume);
+			break;
+
+		case WAIT_OBJECT_0 + 4:
+			// Buffer end
+		do_fill_buffer:
+		{
+			// Time to fill more into buffer
+			if (!playback_should_be_running)
+				break;
+
+			for (int i = 0; i < buffer_length; ++i) {
+				if (!buffer_occupied[i]) {
+					int fill_len = std::min<int>(end_frame - next_input_frame, wanted_frames);
+					if (fill_len <= 0)
+						break;
+					buffer_occupied[i] = true;
+					if (original)
+						provider->GetAudio(buff[i].data(), next_input_frame, fill_len);
+					else
+						provider->GetInt16MonoAudio(reinterpret_cast<int16_t*>(buff[i].data()), next_input_frame, fill_len);
+					next_input_frame += fill_len;
+					XAUDIO2_BUFFER xbf;
+					xbf.Flags = fill_len + next_input_frame == end_frame ? XAUDIO2_END_OF_STREAM : 0;
+					xbf.AudioBytes = fill_len * wfx.nBlockAlign;
+					xbf.pAudioData = buff[i].data();
+					xbf.PlayBegin = 0;
+					xbf.PlayLength = 0;
+					xbf.LoopBegin = 0;
+					xbf.LoopLength = 0;
+					xbf.LoopCount = 0;
+					xbf.pContext = reinterpret_cast<void*>(static_cast<intptr_t>(i));
+					if (FAILED(hr = pSourceVoice->SubmitSourceBuffer(&xbf))) {
+						REPORT_ERROR("Failed initializing Submit Buffer")
+					}
+				}
+			}
+			break;
+
+		case WAIT_OBJECT_0 + 5:
+			// Perform suicide
+			running = false;
+			goto stop_playback;
+		}
+
+		default:
+			REPORT_ERROR("Something bad happened while waiting on events in playback loop, either the wait failed or an event object was abandoned.")
+				break;
+		}
+	}
+}
+
+#undef REPORT_ERROR
+
+void XAudio2Thread::CheckError()
+{
+	try {
+		switch (WaitForSingleObject(error_happened, 0))
+		{
+		case WAIT_OBJECT_0:
+			throw error_message;
+
+		case WAIT_ABANDONED:
+			throw "The XAudio2Thread error signal event was abandoned, somehow. This should not happen.";
+
+		case WAIT_FAILED:
+			throw "Failed checking state of XAudio2Thread error signal event.";
+
+		case WAIT_TIMEOUT:
+		default:
+			return;
+		}
+	}
+	catch (...) {
+		ResetEvent(is_playing);
+		ResetEvent(thread_running);
+		throw;
+	}
+}
+
+XAudio2Thread::XAudio2Thread(agi::AudioProvider* provider, int WantedLatency, int BufferLength)
+	: event_start_playback(CreateEvent(0, FALSE, FALSE, 0))
+	, event_stop_playback(CreateEvent(0, FALSE, FALSE, 0))
+	, event_update_end_time(CreateEvent(0, FALSE, FALSE, 0))
+	, event_set_volume(CreateEvent(0, FALSE, FALSE, 0))
+	, event_buffer_end(CreateEvent(0, FALSE, FALSE, 0))
+	, event_kill_self(CreateEvent(0, FALSE, FALSE, 0))
+	, thread_running(CreateEvent(0, TRUE, FALSE, 0))
+	, is_playing(CreateEvent(0, TRUE, FALSE, 0))
+	, error_happened(CreateEvent(0, FALSE, FALSE, 0))
+	, wanted_latency(WantedLatency)
+	, buffer_length(BufferLength)
+	, provider(provider)
+	, buffer_occupied(BufferLength)
+{
+	if (!(thread_handle = (HANDLE)_beginthreadex(0, 0, ThreadProc, this, 0, 0))) {
+		throw AudioPlayerOpenError("Failed creating playback thread in XAudio2Player. This is bad.");
+	}
+
+	HANDLE running_or_error[] = { thread_running, error_happened };
+	switch (WaitForMultipleObjects(2, running_or_error, FALSE, INFINITE)) {
+	case WAIT_OBJECT_0:
+		// running, all good
+		return;
+
+	case WAIT_OBJECT_0 + 1:
+		// error happened, we fail
+		throw AudioPlayerOpenError(error_message ? error_message : "Failed wait for thread start or thread error in XAudio2Player. This is bad.");
+
+	default:
+		throw AudioPlayerOpenError("Failed wait for thread start or thread error in XAudio2Player. This is bad.");
+	}
+}
+
+XAudio2Thread::~XAudio2Thread() {
+	SetEvent(event_kill_self);
+	WaitForSingleObject(thread_handle, INFINITE);
+}
+
+void XAudio2Thread::Play(int64_t start, int64_t count)
+{
+	CheckError();
+
+	start_frame = start;
+	end_frame = start + count;
+	SetEvent(event_start_playback);
+
+	last_playback_restart = GetTickCount64();
+
+	// Block until playback actually begins to avoid race conditions with
+	// checking if playback is in progress
+	HANDLE events_to_wait[] = { is_playing, error_happened };
+	switch (WaitForMultipleObjects(2, events_to_wait, FALSE, INFINITE)) {
+	case WAIT_OBJECT_0 + 0: // Playing
+		LOG_D("audio/player/xaudio2") << "Playback begun";
+		break;
+	case WAIT_OBJECT_0 + 1: // Error
+		throw error_message;
+	default:
+		throw agi::InternalError("Unexpected result from WaitForMultipleObjects in XAudio2Thread::Play");
+	}
+}
+
+void XAudio2Thread::Stop() {
+	CheckError();
+
+	SetEvent(event_stop_playback);
+}
+
+void XAudio2Thread::SetEndFrame(int64_t new_end_frame) {
+	CheckError();
+
+	end_frame = new_end_frame;
+	SetEvent(event_update_end_time);
+}
+
+void XAudio2Thread::SetVolume(double new_volume) {
+	CheckError();
+
+	volume = new_volume;
+	SetEvent(event_set_volume);
+}
+
+bool XAudio2Thread::IsPlaying() {
+	CheckError();
+
+	switch (WaitForSingleObject(is_playing, 0))
+	{
+	case WAIT_ABANDONED:
+		throw "The XAudio2Thread playback state event was abandoned, somehow. This should not happen.";
+
+	case WAIT_FAILED:
+		throw "Failed checking state of XAudio2Thread playback state event.";
+
+	case WAIT_OBJECT_0:
+		return true;
+
+	case WAIT_TIMEOUT:
+	default:
+		return false;
+	}
+}
+
+int64_t XAudio2Thread::GetCurrentFrame() {
+	CheckError();
+	if (!IsPlaying()) return 0;
+	ULONGLONG milliseconds_elapsed = GetTickCount64() - last_playback_restart;
+	return start_frame + milliseconds_elapsed * provider->GetSampleRate() / 1000;
+}
+
+int64_t XAudio2Thread::GetEndFrame() {
+	CheckError();
+	return end_frame;
+}
+
+bool XAudio2Thread::IsDead() {
+	switch (WaitForSingleObject(thread_running, 0))
+	{
+	case WAIT_OBJECT_0:
+		return false;
+	default:
+		return true;
+	}
+}
+
+XAudio2Player::XAudio2Player(agi::AudioProvider* provider) :AudioPlayer(provider) {
+	// The buffer will hold BufferLength times WantedLatency milliseconds of audio
+	WantedLatency = OPT_GET("Player/Audio/DirectSound/Buffer Latency")->GetInt();
+	BufferLength = OPT_GET("Player/Audio/DirectSound/Buffer Length")->GetInt();
+
+	// sanity checking
+	if (WantedLatency <= 0)
+		WantedLatency = 100;
+	if (BufferLength <= 0)
+		BufferLength = 5;
+
+	try {
+		thread = agi::make_unique<XAudio2Thread>(provider, WantedLatency, BufferLength);
+	}
+	catch (const char* msg) {
+		LOG_E("audio/player/xaudio2") << msg;
+		throw AudioPlayerOpenError(msg);
+	}
+}
+
+bool XAudio2Player::IsThreadAlive() {
+	if (thread && thread->IsDead())
+		thread.reset();
+	return static_cast<bool>(thread);
+}
+
+void XAudio2Player::Play(int64_t start, int64_t count) {
+	try {
+		thread->Play(start, count);
+	}
+	catch (const char* msg) {
+		LOG_E("audio/player/xaudio2") << msg;
+	}
+}
+
+void XAudio2Player::Stop() {
+	try {
+		if (IsThreadAlive()) thread->Stop();
+	}
+	catch (const char* msg) {
+		LOG_E("audio/player/xaudio2") << msg;
+	}
+}
+
+bool XAudio2Player::IsPlaying() {
+	try {
+		if (!IsThreadAlive()) return false;
+		return thread->IsPlaying();
+	}
+	catch (const char* msg) {
+		LOG_E("audio/player/xaudio2") << msg;
+		return false;
+	}
+}
+
+int64_t XAudio2Player::GetEndPosition() {
+	try {
+		if (!IsThreadAlive()) return 0;
+		return thread->GetEndFrame();
+	}
+	catch (const char* msg) {
+		LOG_E("audio/player/xaudio2") << msg;
+		return 0;
+	}
+}
+
+int64_t XAudio2Player::GetCurrentPosition() {
+	try {
+		if (!IsThreadAlive()) return 0;
+		return thread->GetCurrentFrame();
+	}
+	catch (const char* msg) {
+		LOG_E("audio/player/xaudio2") << msg;
+		return 0;
+	}
+}
+
+void XAudio2Player::SetEndPosition(int64_t pos) {
+	try {
+		if (IsThreadAlive()) thread->SetEndFrame(pos);
+	}
+	catch (const char* msg) {
+		LOG_E("audio/player/xaudio2") << msg;
+	}
+}
+
+void XAudio2Player::SetVolume(double vol) {
+	try {
+		if (IsThreadAlive()) thread->SetVolume(vol);
+	}
+	catch (const char* msg) {
+		LOG_E("audio/player/xaudio2") << msg;
+	}
+}
+}
+
+std::unique_ptr<AudioPlayer> CreateXAudio2Player(agi::AudioProvider* provider, wxWindow*) {
+	return agi::make_unique<XAudio2Player>(provider);
+}
+
+#endif // WITH_DIRECTSOUND

src/audio_provider_ffmpegsource.cpp

@@ -167,7 +167,7 @@ void FFmpegSourceAudioProvider::LoadAudio(agi::fs::path const& filename) {
 			throw agi::AudioProviderError("unknown or unsupported sample format");
 	}
 
-#if FFMS_VERSION >= ((2 << 24) | (17 << 16) | (4 << 8) | 0)
+#if defined(FFMS_MONO_OUTPUT) && FFMS_VERSION >= ((2 << 24) | (17 << 16) | (4 << 8) | 0)
 	if (channels > 1 || bytes_per_sample != 2) {
 		std::unique_ptr<FFMS_ResampleOptions, decltype(&FFMS_DestroyResampleOptions)>
 			opt(FFMS_CreateResampleOptions(AudioSource), FFMS_DestroyResampleOptions);