From 80026d7fe631bb2d1fcac37dcc13145c868ecfa2 Mon Sep 17 00:00:00 2001
From: Jack Andersen <jackoalan@gmail.com>
Date: Mon, 16 May 2016 10:21:20 -1000
Subject: [PATCH] Better buffer handling for audio mixing

---
 lib/audiodev/AudioMatrix.cpp | 30 ++++++++++++++++++------------
 lib/audiodev/AudioMatrix.hpp | 24 ++++++++++++------------
 lib/audiodev/AudioVoice.cpp  | 33 ++++++++++++++-------------------
 lib/audiodev/AudioVoice.hpp  |  1 +
 4 files changed, 45 insertions(+), 43 deletions(-)

diff --git a/lib/audiodev/AudioMatrix.cpp b/lib/audiodev/AudioMatrix.cpp
index 4510937..995ae49 100644
--- a/lib/audiodev/AudioMatrix.cpp
+++ b/lib/audiodev/AudioMatrix.cpp
@@ -23,8 +23,8 @@ void AudioMatrixMono::setDefaultMatrixCoefficients(AudioChannelSet acSet)
     }
 }
 
-void AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
-                                        const int16_t* dataIn, int16_t* dataOut, size_t samples) const
+int16_t* AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
+                                            const int16_t* dataIn, int16_t* dataOut, size_t samples) const
 {
     const ChannelMap& chmap = info.m_channelMap;
     for (size_t s=0 ; s<samples ; ++s, ++dataIn)
@@ -37,10 +37,11 @@ void AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
                 ++dataOut;
             }
         }
+    return dataOut;
 }
 
-void AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
-                                        const int32_t* dataIn, int32_t* dataOut, size_t samples) const
+int32_t* AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
+                                            const int32_t* dataIn, int32_t* dataOut, size_t samples) const
 {
     const ChannelMap& chmap = info.m_channelMap;
     for (size_t s=0 ; s<samples ; ++s, ++dataIn)
@@ -53,10 +54,11 @@ void AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
                 ++dataOut;
             }
         }
+    return dataOut;
 }
 
-void AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
-                                        const float* dataIn, float* dataOut, size_t samples) const
+float* AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
+                                          const float* dataIn, float* dataOut, size_t samples) const
 {
     const ChannelMap& chmap = info.m_channelMap;
     for (size_t s=0 ; s<samples ; ++s, ++dataIn)
@@ -69,6 +71,7 @@ void AudioMatrixMono::mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
                 ++dataOut;
             }
         }
+    return dataOut;
 }
 
 void AudioMatrixStereo::setDefaultMatrixCoefficients(AudioChannelSet acSet)
@@ -90,8 +93,8 @@ void AudioMatrixStereo::setDefaultMatrixCoefficients(AudioChannelSet acSet)
     }
 }
 
-void AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
-                                            const int16_t* dataIn, int16_t* dataOut, size_t frames) const
+int16_t* AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
+                                                const int16_t* dataIn, int16_t* dataOut, size_t frames) const
 {
     const ChannelMap& chmap = info.m_channelMap;
     for (size_t f=0 ; f<frames ; ++f, dataIn += 2)
@@ -106,10 +109,11 @@ void AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
                 ++dataOut;
             }
         }
+    return dataOut;
 }
 
-void AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
-                                            const int32_t* dataIn, int32_t* dataOut, size_t frames) const
+int32_t* AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
+                                                const int32_t* dataIn, int32_t* dataOut, size_t frames) const
 {
     const ChannelMap& chmap = info.m_channelMap;
     for (size_t f=0 ; f<frames ; ++f, dataIn += 2)
@@ -124,10 +128,11 @@ void AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
                 ++dataOut;
             }
         }
+    return dataOut;
 }
 
-void AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
-                                            const float* dataIn, float* dataOut, size_t frames) const
+float* AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
+                                              const float* dataIn, float* dataOut, size_t frames) const
 {
     const ChannelMap& chmap = info.m_channelMap;
     for (size_t f=0 ; f<frames ; ++f, dataIn += 2)
@@ -142,6 +147,7 @@ void AudioMatrixStereo::mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
                 ++dataOut;
             }
         }
+    return dataOut;
 }
 
 }
diff --git a/lib/audiodev/AudioMatrix.hpp b/lib/audiodev/AudioMatrix.hpp
index 212a2cb..25f33d5 100644
--- a/lib/audiodev/AudioMatrix.hpp
+++ b/lib/audiodev/AudioMatrix.hpp
@@ -50,12 +50,12 @@ public:
             m_coefs[i] = coefs[i];
     }
 
-    void mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
-                           const int16_t* dataIn, int16_t* dataOut, size_t samples) const;
-    void mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
-                           const int32_t* dataIn, int32_t* dataOut, size_t samples) const;
-    void mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
-                           const float* dataIn, float* dataOut, size_t samples) const;
+    int16_t* mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
+                               const int16_t* dataIn, int16_t* dataOut, size_t samples) const;
+    int32_t* mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
+                               const int32_t* dataIn, int32_t* dataOut, size_t samples) const;
+    float* mixMonoSampleData(const AudioVoiceEngineMixInfo& info,
+                             const float* dataIn, float* dataOut, size_t samples) const;
 };
 
 class AudioMatrixStereo
@@ -74,12 +74,12 @@ public:
         }
     }
 
-    void mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
-                             const int16_t* dataIn, int16_t* dataOut, size_t frames) const;
-    void mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
-                             const int32_t* dataIn, int32_t* dataOut, size_t frames) const;
-    void mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
-                             const float* dataIn, float* dataOut, size_t frames) const;
+    int16_t* mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
+                                 const int16_t* dataIn, int16_t* dataOut, size_t frames) const;
+    int32_t* mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
+                                 const int32_t* dataIn, int32_t* dataOut, size_t frames) const;
+    float* mixStereoSampleData(const AudioVoiceEngineMixInfo& info,
+                               const float* dataIn, float* dataOut, size_t frames) const;
 };
 
 }
diff --git a/lib/audiodev/AudioVoice.cpp b/lib/audiodev/AudioVoice.cpp
index aa46030..a647206 100644
--- a/lib/audiodev/AudioVoice.cpp
+++ b/lib/audiodev/AudioVoice.cpp
@@ -20,7 +20,7 @@ void AudioVoice::_setPitchRatio(double ratio)
 {
     if (m_dynamicRate)
     {
-        soxr_error_t err = soxr_set_io_ratio(m_src, ratio * m_sampleRateIn / m_sampleRateOut, 0 /*m_parent.mixInfo().m_periodFrames*/);
+        soxr_error_t err = soxr_set_io_ratio(m_src, ratio * m_sampleRateIn / m_sampleRateOut, 0);
         if (err)
         {
             Log.report(logvisor::Fatal, "unable to set resampler rate: %s", soxr_strerror(err));
@@ -98,6 +98,7 @@ void AudioVoiceMono::_resetSampleRate(double sampleRate)
 
     m_sampleRateIn = sampleRate;
     m_sampleRateOut = rateOut;
+    m_5msFrames = rateOut * 5 / 1000;
     soxr_set_input_fn(m_src, soxr_input_fn_t(SRCCallback), this, 0);
     _setPitchRatio(m_pitchRatio);
     m_resetSampleRate = false;
@@ -123,14 +124,13 @@ size_t AudioVoiceMono::pumpAndMix(const AudioVoiceEngineMixInfo& mixInfo,
     size_t totalDone = 0;
     while (frames)
     {
-        oDone = soxr_output(m_src, scratch16.data(), frames);
+        oDone = soxr_output(m_src, scratch16.data(), m_5msFrames);
         _midUpdate();
         if (oDone)
         {
-            m_matrix.mixMonoSampleData(mixInfo, scratch16.data(), buf, oDone);
+            buf = m_matrix.mixMonoSampleData(mixInfo, scratch16.data(), buf, oDone);
             totalDone += oDone;
             frames -= oDone;
-            buf += oDone;
         }
     }
 
@@ -148,14 +148,13 @@ size_t AudioVoiceMono::pumpAndMix(const AudioVoiceEngineMixInfo& mixInfo,
     size_t totalDone = 0;
     while (frames)
     {
-        oDone = soxr_output(m_src, scratch32.data(), frames);
+        oDone = soxr_output(m_src, scratch32.data(), m_5msFrames);
         _midUpdate();
         if (oDone)
         {
-            m_matrix.mixMonoSampleData(mixInfo, scratch32.data(), buf, oDone);
+            buf = m_matrix.mixMonoSampleData(mixInfo, scratch32.data(), buf, oDone);
             totalDone += oDone;
             frames -= oDone;
-            buf += oDone;
         }
     }
 
@@ -173,14 +172,13 @@ size_t AudioVoiceMono::pumpAndMix(const AudioVoiceEngineMixInfo& mixInfo,
     size_t totalDone = 0;
     while (frames)
     {
-        oDone = soxr_output(m_src, scratchFlt.data(), frames);
+        oDone = soxr_output(m_src, scratchFlt.data(), m_5msFrames);
         _midUpdate();
         if (oDone)
         {
-            m_matrix.mixMonoSampleData(mixInfo, scratchFlt.data(), buf, oDone);
+            buf = m_matrix.mixMonoSampleData(mixInfo, scratchFlt.data(), buf, oDone);
             totalDone += oDone;
             frames -= oDone;
-            buf += oDone;
         }
     }
 
@@ -268,14 +266,13 @@ size_t AudioVoiceStereo::pumpAndMix(const AudioVoiceEngineMixInfo& mixInfo,
     size_t totalDone = 0;
     while (frames)
     {
-        oDone = soxr_output(m_src, scratch16.data(), frames);
+        oDone = soxr_output(m_src, scratch16.data(), m_5msFrames);
         _midUpdate();
         if (oDone)
         {
-            m_matrix.mixStereoSampleData(mixInfo, scratch16.data(), buf, oDone);
+            buf = m_matrix.mixStereoSampleData(mixInfo, scratch16.data(), buf, oDone);
             totalDone += oDone;
             frames -= oDone;
-            buf += oDone;
         }
     }
 
@@ -294,14 +291,13 @@ size_t AudioVoiceStereo::pumpAndMix(const AudioVoiceEngineMixInfo& mixInfo,
     size_t totalDone = 0;
     while (frames)
     {
-        oDone = soxr_output(m_src, scratch32.data(), frames);
+        oDone = soxr_output(m_src, scratch32.data(), m_5msFrames);
         _midUpdate();
         if (oDone)
         {
-            m_matrix.mixStereoSampleData(mixInfo, scratch32.data(), buf, oDone);
+            buf = m_matrix.mixStereoSampleData(mixInfo, scratch32.data(), buf, oDone);
             totalDone += oDone;
             frames -= oDone;
-            buf += oDone;
         }
     }
 
@@ -320,14 +316,13 @@ size_t AudioVoiceStereo::pumpAndMix(const AudioVoiceEngineMixInfo& mixInfo,
     size_t totalDone = 0;
     while (frames)
     {
-        oDone = soxr_output(m_src, scratchFlt.data(), frames);
+        oDone = soxr_output(m_src, scratchFlt.data(), m_5msFrames);
         _midUpdate();
         if (oDone)
         {
-            m_matrix.mixStereoSampleData(mixInfo, scratchFlt.data(), buf, oDone);
+            buf = m_matrix.mixStereoSampleData(mixInfo, scratchFlt.data(), buf, oDone);
             totalDone += oDone;
             frames -= oDone;
-            buf += oDone;
         }
     }
 
diff --git a/lib/audiodev/AudioVoice.hpp b/lib/audiodev/AudioVoice.hpp
index 18667ce..5ff0635 100644
--- a/lib/audiodev/AudioVoice.hpp
+++ b/lib/audiodev/AudioVoice.hpp
@@ -36,6 +36,7 @@ protected:
     soxr_t m_src = nullptr;
     double m_sampleRateIn;
     double m_sampleRateOut;
+    size_t m_5msFrames;
     bool m_dynamicRate;
 
     /* Running bool */