From befa1a11a29e279408a7e97478a565078e499e70 Mon Sep 17 00:00:00 2001
From: Jack Andersen <jackoalan@gmail.com>
Date: Sun, 3 Jul 2016 17:31:53 -1000
Subject: [PATCH] ALSA and AQS use floating-point audio output now

---
 lib/audiodev/ALSA.cpp       |  8 +++++++-
 lib/audiodev/AQS.cpp        | 10 +++++-----
 lib/audiodev/AudioVoice.cpp |  8 ++++----
 3 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/lib/audiodev/ALSA.cpp b/lib/audiodev/ALSA.cpp
index ba2a041..1b81785 100644
--- a/lib/audiodev/ALSA.cpp
+++ b/lib/audiodev/ALSA.cpp
@@ -135,7 +135,13 @@ struct ALSAAudioVoiceEngine : BaseAudioVoiceEngine
         snd_pcm_hw_params_any(m_pcm, hwParams);
 
         snd_pcm_format_t bestFmt;
-        if (!snd_pcm_hw_params_test_format(m_pcm, hwParams, SND_PCM_FORMAT_S32))
+        if (!snd_pcm_hw_params_test_format(m_pcm, hwParams, SND_PCM_FORMAT_FLOAT))
+        {
+            bestFmt = SND_PCM_FORMAT_FLOAT;
+            m_mixInfo.m_sampleFormat = SOXR_FLOAT32_I;
+            m_mixInfo.m_bitsPerSample = 32;
+        }
+        else if (!snd_pcm_hw_params_test_format(m_pcm, hwParams, SND_PCM_FORMAT_S32))
         {
             bestFmt = SND_PCM_FORMAT_S32;
             m_mixInfo.m_sampleFormat = SOXR_INT32_I;
diff --git a/lib/audiodev/AQS.cpp b/lib/audiodev/AQS.cpp
index 0ea579c..43871f7 100644
--- a/lib/audiodev/AQS.cpp
+++ b/lib/audiodev/AQS.cpp
@@ -56,7 +56,7 @@ struct AQSAudioVoiceEngine : BaseAudioVoiceEngine
         engine->m_engineEnterCv.wait(lk);
         engine->m_cbWaiting = false;
 
-        engine->_pumpAndMixVoices(engine->m_mixInfo.m_periodFrames, reinterpret_cast<int32_t*>(inBuffer->mAudioData));
+        engine->_pumpAndMixVoices(engine->m_mixInfo.m_periodFrames, reinterpret_cast<float*>(inBuffer->mAudioData));
         inBuffer->mAudioDataByteSize = engine->m_frameBytes;
         AudioQueueEnqueueBuffer(inAQ, inBuffer, 0, nullptr);
 
@@ -71,7 +71,7 @@ struct AQSAudioVoiceEngine : BaseAudioVoiceEngine
         AudioStreamBasicDescription desc = {};
         desc.mSampleRate = 96000;
         desc.mFormatID = kAudioFormatLinearPCM;
-        desc.mFormatFlags = kLinearPCMFormatFlagIsSignedInteger;
+        desc.mFormatFlags = kLinearPCMFormatFlagIsFloat;
         desc.mBytesPerPacket = chCount * 4;
         desc.mFramesPerPacket = 1;
         desc.mBytesPerFrame = chCount * 4;
@@ -545,7 +545,7 @@ struct AQSAudioVoiceEngine : BaseAudioVoiceEngine
         AudioStreamBasicDescription desc = {};
         desc.mSampleRate = 96000;
         desc.mFormatID = kAudioFormatLinearPCM;
-        desc.mFormatFlags = kLinearPCMFormatFlagIsSignedInteger;
+        desc.mFormatFlags = kLinearPCMFormatFlagIsFloat;
         desc.mBytesPerPacket = chCount * 4;
         desc.mFramesPerPacket = 1;
         desc.mBytesPerFrame = chCount * 4;
@@ -579,7 +579,7 @@ struct AQSAudioVoiceEngine : BaseAudioVoiceEngine
         }
 
         m_mixInfo.m_sampleRate = actualSampleRate;
-        m_mixInfo.m_sampleFormat = SOXR_INT32_I;
+        m_mixInfo.m_sampleFormat = SOXR_FLOAT32_I;
         m_mixInfo.m_bitsPerSample = 32;
         m_5msFrames = actualSampleRate * 5 / 1000;
 
@@ -676,7 +676,7 @@ struct AQSAudioVoiceEngine : BaseAudioVoiceEngine
 
         for (unsigned i=0 ; i<3 ; ++i)
         {
-            _pumpAndMixVoices(m_mixInfo.m_periodFrames, reinterpret_cast<int32_t*>(m_buffers[i]->mAudioData));
+            _pumpAndMixVoices(m_mixInfo.m_periodFrames, reinterpret_cast<float*>(m_buffers[i]->mAudioData));
             m_buffers[i]->mAudioDataByteSize = m_frameBytes;
             AudioQueueEnqueueBuffer(m_queue, m_buffers[i], 0, nullptr);
         }
diff --git a/lib/audiodev/AudioVoice.cpp b/lib/audiodev/AudioVoice.cpp
index a3b976c..0928589 100644
--- a/lib/audiodev/AudioVoice.cpp
+++ b/lib/audiodev/AudioVoice.cpp
@@ -127,7 +127,7 @@ void AudioVoiceMono::_resetSampleRate(double sampleRate)
     {
         std::vector<float>& scratchFlt = m_root.m_scratchFlt;
         if (scratchFlt.size() < m_root.m_5msFrames)
-            scratchFlt.resize(m_root.m_5msFrames);
+            scratchFlt.resize(m_root.m_5msFrames + 2);
         soxr_output(m_src, scratchFlt.data(), m_root.m_5msFrames);
         break;
     }
@@ -196,7 +196,7 @@ size_t AudioVoiceMono::pumpAndMix(const AudioVoiceEngineMixInfo& mixInfo,
 {
     std::vector<float>& scratchFlt = m_root.m_scratchFlt;
     if (scratchFlt.size() < frames)
-        scratchFlt.resize(frames);
+        scratchFlt.resize(frames + 2);
 
     size_t oDone = soxr_output(m_src, scratchFlt.data(), frames);
     _midUpdate();
@@ -316,7 +316,7 @@ void AudioVoiceStereo::_resetSampleRate(double sampleRate)
     {
         std::vector<float>& scratchFlt = m_root.m_scratchFlt;
         if (scratchFlt.size() < m_root.m_5msFrames * 2)
-            scratchFlt.resize(m_root.m_5msFrames * 2);
+            scratchFlt.resize(m_root.m_5msFrames * 2 + 2);
         soxr_output(m_src, scratchFlt.data(), m_root.m_5msFrames);
         break;
     }
@@ -389,7 +389,7 @@ size_t AudioVoiceStereo::pumpAndMix(const AudioVoiceEngineMixInfo& mixInfo,
     std::vector<float>& scratchFlt = m_root.m_scratchFlt;
     size_t samples = frames * 2;
     if (scratchFlt.size() < samples)
-        scratchFlt.resize(samples);
+        scratchFlt.resize(samples + 4);
 
     size_t oDone = soxr_output(m_src, scratchFlt.data(), frames);
     _midUpdate();