#include "../session.h" #include "renderers/renderer.h" #ifdef HAVE_SOUNDIO #include "renderers/soundioaudiorenderer.h" #endif #ifdef HAVE_SLAUDIO #include "renderers/slaud.h" #endif #include "renderers/sdl.h" #include #define TRY_INIT_RENDERER(renderer, opusConfig) \ { \ IAudioRenderer* __renderer = new renderer(); \ if (__renderer->prepareForPlayback(opusConfig)) \ return __renderer; \ delete __renderer; \ } IAudioRenderer* Session::createAudioRenderer(const POPUS_MULTISTREAM_CONFIGURATION opusConfig) { // Handle explicit ML_AUDIO setting and fail if the requested backend fails QString mlAudio = qgetenv("ML_AUDIO").toLower(); if (mlAudio == "sdl") { TRY_INIT_RENDERER(SdlAudioRenderer, opusConfig) return nullptr; } #ifdef HAVE_SOUNDIO else if (mlAudio == "libsoundio") { TRY_INIT_RENDERER(SoundIoAudioRenderer, opusConfig) return nullptr; } #endif #if defined(HAVE_SLAUDIO) else if (mlAudio == "slaudio") { TRY_INIT_RENDERER(SLAudioRenderer, opusConfig) return nullptr; } #endif else if (!mlAudio.isEmpty()) { SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Unknown audio backend: %s", SDL_getenv("ML_AUDIO")); return nullptr; } // -------------- Automatic backend selection below this line --------------- #if defined(HAVE_SLAUDIO) // Steam Link should always have SLAudio TRY_INIT_RENDERER(SLAudioRenderer, opusConfig) #endif #if !defined(Q_OS_WIN32) && !defined(Q_OS_DARWIN) // Linux defaults to SDL due to persistent glitching issues under libsoundio. // Platforms that libsoundio doesn't support also default to SDL. TRY_INIT_RENDERER(SdlAudioRenderer, opusConfig) #ifdef HAVE_SOUNDIO TRY_INIT_RENDERER(SoundIoAudioRenderer, opusConfig) #endif #else // Windows and macOS default to libsoundio and fall back to SDL #ifdef HAVE_SOUNDIO TRY_INIT_RENDERER(SoundIoAudioRenderer, opusConfig) #endif TRY_INIT_RENDERER(SdlAudioRenderer, opusConfig) #endif return nullptr; } int Session::getAudioRendererCapabilities(int audioConfiguration) { // Build a fake OPUS_MULTISTREAM_CONFIGURATION to give // the renderer the channel count and sample rate. OPUS_MULTISTREAM_CONFIGURATION opusConfig = {}; opusConfig.sampleRate = 48000; opusConfig.samplesPerFrame = 240; opusConfig.channelCount = CHANNEL_COUNT_FROM_AUDIO_CONFIGURATION(audioConfiguration); IAudioRenderer* audioRenderer = createAudioRenderer(&opusConfig); if (audioRenderer == nullptr) { return 0; } int caps = audioRenderer->getCapabilities(); delete audioRenderer; return caps; } bool Session::testAudio(int audioConfiguration) { // Build a fake OPUS_MULTISTREAM_CONFIGURATION to give // the renderer the channel count and sample rate. OPUS_MULTISTREAM_CONFIGURATION opusConfig = {}; opusConfig.sampleRate = 48000; opusConfig.samplesPerFrame = 240; opusConfig.channelCount = CHANNEL_COUNT_FROM_AUDIO_CONFIGURATION(audioConfiguration); IAudioRenderer* audioRenderer = createAudioRenderer(&opusConfig); if (audioRenderer == nullptr) { return false; } delete audioRenderer; return true; } int Session::arInit(int /* audioConfiguration */, const POPUS_MULTISTREAM_CONFIGURATION opusConfig, void* /* arContext */, int /* arFlags */) { int error; SDL_memcpy(&s_ActiveSession->m_AudioConfig, opusConfig, sizeof(*opusConfig)); s_ActiveSession->m_AudioRenderer = s_ActiveSession->createAudioRenderer(&s_ActiveSession->m_AudioConfig); if (s_ActiveSession->m_AudioRenderer == nullptr) { return -2; } // Allow the chosen renderer to remap Opus channels as needed to ensure proper output s_ActiveSession->m_AudioRenderer->remapChannels(&s_ActiveSession->m_AudioConfig); // Create the Opus decoder with the renderer's preferred channel mapping s_ActiveSession->m_OpusDecoder = opus_multistream_decoder_create(s_ActiveSession->m_AudioConfig.sampleRate, s_ActiveSession->m_AudioConfig.channelCount, s_ActiveSession->m_AudioConfig.streams, s_ActiveSession->m_AudioConfig.coupledStreams, s_ActiveSession->m_AudioConfig.mapping, &error); if (s_ActiveSession->m_OpusDecoder == NULL) { delete s_ActiveSession->m_AudioRenderer; s_ActiveSession->m_AudioRenderer = nullptr; SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Failed to create decoder: %d", error); return -1; } SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, "Audio stream has %d channels", s_ActiveSession->m_AudioConfig.channelCount); return 0; } void Session::arCleanup() { delete s_ActiveSession->m_AudioRenderer; s_ActiveSession->m_AudioRenderer = nullptr; opus_multistream_decoder_destroy(s_ActiveSession->m_OpusDecoder); s_ActiveSession->m_OpusDecoder = nullptr; } void Session::arDecodeAndPlaySample(char* sampleData, int sampleLength) { int samplesDecoded; #ifndef STEAM_LINK // Set this thread to high priority to reduce the chance of missing // our sample delivery time. On Steam Link, this causes starvation // of other threads due to severely restricted CPU time available, // so we will skip it on that platform. if (s_ActiveSession->m_AudioSampleCount == 0) { if (SDL_SetThreadPriority(SDL_THREAD_PRIORITY_HIGH) < 0) { SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION, "Unable to set audio thread to high priority: %s", SDL_GetError()); } } #endif // See if we need to drop this sample if (s_ActiveSession->m_DropAudioEndTime != 0) { if (SDL_TICKS_PASSED(SDL_GetTicks(), s_ActiveSession->m_DropAudioEndTime)) { // Avoid calling SDL_GetTicks() now s_ActiveSession->m_DropAudioEndTime = 0; SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, "Audio drop window has ended"); } else { // We're still in the drop window return; } } s_ActiveSession->m_AudioSampleCount++; if (s_ActiveSession->m_AudioRenderer != nullptr) { int desiredSize = sizeof(short) * s_ActiveSession->m_AudioConfig.samplesPerFrame * s_ActiveSession->m_AudioConfig.channelCount; void* buffer = s_ActiveSession->m_AudioRenderer->getAudioBuffer(&desiredSize); if (buffer == nullptr) { return; } samplesDecoded = opus_multistream_decode(s_ActiveSession->m_OpusDecoder, (unsigned char*)sampleData, sampleLength, (short*)buffer, desiredSize / sizeof(short) / s_ActiveSession->m_AudioConfig.channelCount, 0); // Update desiredSize with the number of bytes actually populated by the decoding operation if (samplesDecoded > 0) { SDL_assert(desiredSize >= (int)(sizeof(short) * samplesDecoded * s_ActiveSession->m_AudioConfig.channelCount)); desiredSize = sizeof(short) * samplesDecoded * s_ActiveSession->m_AudioConfig.channelCount; } else { desiredSize = 0; } if (!s_ActiveSession->m_AudioRenderer->submitAudio(desiredSize)) { SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION, "Reinitializing audio renderer after failure"); delete s_ActiveSession->m_AudioRenderer; s_ActiveSession->m_AudioRenderer = nullptr; } } // Only try to recreate the audio renderer every 200 samples (1 second) // to avoid thrashing if the audio device is unavailable. It is // safe to reinitialize here because we can't be torn down while // the audio decoder/playback thread is still alive. if (s_ActiveSession->m_AudioRenderer == nullptr && (s_ActiveSession->m_AudioSampleCount % 200) == 0) { // Since we're doing this inline and audio initialization takes time, we need // to drop samples to account for the time we've spent blocking audio rendering // so we return to real-time playback and don't accumulate latency. Uint32 audioReinitStartTime = SDL_GetTicks(); s_ActiveSession->m_AudioRenderer = s_ActiveSession->createAudioRenderer(&s_ActiveSession->m_AudioConfig); Uint32 audioReinitStopTime = SDL_GetTicks(); s_ActiveSession->m_DropAudioEndTime = audioReinitStopTime + (audioReinitStopTime - audioReinitStartTime); SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, "Audio reinitialization took %d ms - starting drop window", audioReinitStopTime - audioReinitStartTime); } }