Rewrite streaming code to C++ and forklift most of the setup out of the GUI code

2026-04-17 22:00:05 +00:00 · 2018-06-28 01:44:43 -07:00
parent cad95f12f6
commit 0821c66d8c
13 changed files with 532 additions and 359 deletions
--- a/app/streaming/audio.cpp
+++ b/app/streaming/audio.cpp
@@ -0,0 +1,133 @@
+#include "session.hpp"
+
+#include <Limelight.h>
+#include <SDL.h>
+
+#define MAX_CHANNELS 6
+#define SAMPLES_PER_FRAME 240
+
+SDL_AudioDeviceID Session::s_AudioDevice;
+OpusMSDecoder* Session::s_OpusDecoder;
+short Session::s_OpusDecodeBuffer[MAX_CHANNELS * SAMPLES_PER_FRAME];
+int Session::s_ChannelCount;
+
+int Session::sdlDetermineAudioConfiguration()
+{
+    SDL_AudioSpec want, have;
+    SDL_AudioDeviceID dev;
+
+    SDL_zero(want);
+    want.freq = 48000;
+    want.format = AUDIO_S16;
+    want.channels = 6;
+    want.samples = 1024;
+
+    // Try to open for 5.1 surround sound, but allow SDL to tell us that's
+    // not available.
+    dev = SDL_OpenAudioDevice(NULL, 0, &want, &have, SDL_AUDIO_ALLOW_CHANNELS_CHANGE);
+    if (dev == 0) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
+                     "Failed to open audio device");
+        // We'll probably have issues during audio stream init, but we'll
+        // try anyway
+        return AUDIO_CONFIGURATION_STEREO;
+    }
+
+    SDL_CloseAudioDevice(dev);
+
+    SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION,
+                "Audio device has %d channels", have.channels);
+
+    if (have.channels > 2) {
+        // We don't support quadraphonic or 7.1 surround, but SDL
+        // should be able to downmix or upmix better from 5.1 than
+        // from stereo, so use 5.1 in non-stereo cases.
+        return AUDIO_CONFIGURATION_51_SURROUND;
+    }
+    else {
+        return AUDIO_CONFIGURATION_STEREO;
+    }
+}
+
+int Session::sdlAudioInit(int audioConfiguration,
+                          POPUS_MULTISTREAM_CONFIGURATION opusConfig,
+                          void* arContext, int arFlags)
+{
+    SDL_AudioSpec want, have;
+    int error;
+
+    SDL_zero(want);
+    want.freq = opusConfig->sampleRate;
+    want.format = AUDIO_S16;
+    want.channels = opusConfig->channelCount;
+    want.samples = 1024;
+
+    s_AudioDevice = SDL_OpenAudioDevice(NULL, 0, &want, &have, 0);
+    if (s_AudioDevice == 0) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
+                     "Failed to open audio device: %s",
+                     SDL_GetError());
+        return -1;
+    }
+
+    s_OpusDecoder = opus_multistream_decoder_create(opusConfig->sampleRate,
+                                                    opusConfig->channelCount,
+                                                    opusConfig->streams,
+                                                    opusConfig->coupledStreams,
+                                                    opusConfig->mapping,
+                                                    &error);
+    if (s_OpusDecoder == NULL) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
+                     "Failed to create decoder: %d",
+                     error);
+        SDL_CloseAudioDevice(s_AudioDevice);
+        s_AudioDevice = 0;
+        return -2;
+    }
+
+    s_ChannelCount = opusConfig->channelCount;
+
+    return 0;
+}
+
+void Session::sdlAudioStart()
+{
+    // Unpause the audio device
+    SDL_PauseAudioDevice(s_AudioDevice, 0);
+}
+
+void Session::sdlAudioStop()
+{
+    // Pause the audio device
+    SDL_PauseAudioDevice(s_AudioDevice, 1);
+}
+
+void Session::sdlAudioCleanup()
+{
+    SDL_CloseAudioDevice(s_AudioDevice);
+    s_AudioDevice = 0;
+
+    opus_multistream_decoder_destroy(s_OpusDecoder);
+    s_OpusDecoder = NULL;
+}
+
+void Session::sdlAudioDecodeAndPlaySample(char* sampleData, int sampleLength)
+{
+    int samplesDecoded;
+
+    samplesDecoded = opus_multistream_decode(s_OpusDecoder,
+                                             (unsigned char*)sampleData,
+                                             sampleLength,
+                                             s_OpusDecodeBuffer,
+                                             SAMPLES_PER_FRAME,
+                                             0);
+    if (samplesDecoded > 0) {
+        if (SDL_QueueAudio(s_AudioDevice,
+                           s_OpusDecodeBuffer,
+                           sizeof(short) * samplesDecoded * s_ChannelCount) < 0) {
+            SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
+                         "Failed to queue audio sample: %s",
+                         SDL_GetError());
+        }
+    }
+}