AudioCommon: add Cubeb backend

2025-07-21 05:09:34 -06:00 · 2017-03-22 16:09:59 -07:00
parent 17f4413143
commit f6e1da0dc0
8 changed files with 168 additions and 4 deletions
--- a/Source/Core/AudioCommon/CubebStream.cpp
+++ b/Source/Core/AudioCommon/CubebStream.cpp
@ -0,0 +1,115 @@
+// Copyright 2017 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include <cubeb/cubeb.h>
+
+#include "AudioCommon/CubebStream.h"
+#include "AudioCommon/DPL2Decoder.h"
+#include "Common/CommonTypes.h"
+#include "Common/Logging/Log.h"
+#include "Common/Thread.h"
+#include "Core/ConfigManager.h"
+
+// ~10 ms - needs to be at least 240 for surround
+constexpr u32 BUFFER_SAMPLES = 512;
+
+long CubebStream::DataCallback(cubeb_stream* stream, void* user_data, const void* /*input_buffer*/,
+                               void* output_buffer, long num_frames)
+{
+  auto* self = static_cast<CubebStream*>(user_data);
+
+  if (self->m_stereo)
+  {
+    self->m_mixer->Mix(static_cast<short*>(output_buffer), num_frames);
+  }
+  else
+  {
+    size_t required_capacity = num_frames * 2;
+    if (required_capacity > self->m_short_buffer.capacity() ||
+        required_capacity > self->m_floatstereo_buffer.capacity())
+    {
+      INFO_LOG(AUDIO, "Expanding conversion buffers size: %li frames", num_frames);
+      self->m_short_buffer.reserve(required_capacity);
+      self->m_floatstereo_buffer.reserve(required_capacity);
+    }
+
+    self->m_mixer->Mix(self->m_short_buffer.data(), num_frames);
+
+    // s16 to float
+    for (size_t i = 0; i < static_cast<size_t>(num_frames) * 2; ++i)
+      self->m_floatstereo_buffer[i] = self->m_short_buffer[i] / static_cast<float>(1 << 15);
+
+    // DPL2Decode output: LEFTFRONT, RIGHTFRONT, CENTREFRONT, (sub), LEFTREAR, RIGHTREAR
+    DPL2Decode(self->m_floatstereo_buffer.data(), num_frames, static_cast<float*>(output_buffer));
+  }
+
+  return num_frames;
+}
+
+void CubebStream::StateCallback(cubeb_stream* stream, void* user_data, cubeb_state state)
+{
+}
+
+bool CubebStream::Start()
+{
+  if (cubeb_init(&m_ctx, "Dolphin", nullptr) != CUBEB_OK)
+  {
+    ERROR_LOG(AUDIO, "Error initializing cubeb library");
+    return false;
+  }
+
+  INFO_LOG(AUDIO, "Cubeb initialized using %s backend", cubeb_get_backend_id(m_ctx));
+
+  m_stereo = !SConfig::GetInstance().bDPL2Decoder;
+
+  cubeb_stream_params params;
+  params.rate = m_mixer->GetSampleRate();
+  if (m_stereo)
+  {
+    params.channels = 2;
+    params.format = CUBEB_SAMPLE_S16NE;
+    params.layout = CUBEB_LAYOUT_STEREO;
+  }
+  else
+  {
+    params.channels = 6;
+    params.format = CUBEB_SAMPLE_FLOAT32NE;
+    params.layout = CUBEB_LAYOUT_3F2_LFE;
+  }
+
+  u32 minimum_latency = 0;
+  if (cubeb_get_min_latency(m_ctx, params, &minimum_latency) != CUBEB_OK)
+    ERROR_LOG(AUDIO, "Error getting minimum latency");
+  INFO_LOG(AUDIO, "Minimum latency: %i frames", minimum_latency);
+
+  if (cubeb_stream_init(m_ctx, &m_stream, "Dolphin Audio Output", nullptr, nullptr, nullptr,
+                        &params, std::max(BUFFER_SAMPLES, minimum_latency), DataCallback,
+                        StateCallback, this) != CUBEB_OK)
+  {
+    ERROR_LOG(AUDIO, "Error initializing cubeb stream");
+    return false;
+  }
+
+  if (cubeb_stream_start(m_stream) != CUBEB_OK)
+  {
+    ERROR_LOG(AUDIO, "Error starting cubeb stream");
+    return false;
+  }
+  return true;
+}
+
+void CubebStream::Stop()
+{
+  if (cubeb_stream_stop(m_stream) != CUBEB_OK)
+  {
+    ERROR_LOG(AUDIO, "Error stopping cubeb stream");
+  }
+  cubeb_stream_destroy(m_stream);
+  cubeb_destroy(m_ctx);
+}
+
+void CubebStream::SetVolume(int volume)
+{
+  cubeb_stream_set_volume(m_stream, volume / 100.0f);
+}