[PATCH] [AE/CA] - add soft limiter / volume amplification

xbmc · Nov 13, 2012 · ea8c26b · ea8c26b
1 parent 970818e
commit ea8c26b
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Showing 2 changed files with 26 additions and 1 deletion.
diff --git a/xbmc/cores/AudioEngine/Engines/CoreAudio/CoreAudioAEStream.cpp b/xbmc/cores/AudioEngine/Engines/CoreAudio/CoreAudioAEStream.cpp
@@ -132,6 +132,7 @@ CCoreAudioAEStream::CCoreAudioAEStream(enum AEDataFormat dataFormat, unsigned in
   m_vizRemapBuffer                = (uint8_t *)_aligned_malloc(m_vizRemapBufferSize,16);
 
   m_isRaw                         = COREAUDIO_IS_RAW(dataFormat);
+  m_limiter.SetSamplerate(AE.GetSampleRate());
 }
 
 CCoreAudioAEStream::~CCoreAudioAEStream()
@@ -453,14 +454,14 @@ unsigned int CCoreAudioAEStream::GetFrames(uint8_t *buffer, unsigned int size)
   {
     float *floatBuffer   = (float *)buffer;
     unsigned int samples = readsize / m_OutputBytesPerSample;
+    unsigned int frames         = samples / m_chLayoutCountOutput;
 
     // we have a frame, if we have a viz we need to hand the data to it.
     // Keep in mind that our buffer is already in output format.
     // So we remap output format to viz format !!!
     if (m_OutputFormat.m_dataFormat == AE_FMT_FLOAT)
     {
       // TODO : Why the hell is vizdata limited ?
-      unsigned int frames         = samples / m_chLayoutCountOutput;
       unsigned int samplesClamped = (samples > 512) ? 512 : samples;
       if (samplesClamped)
       {
@@ -498,6 +499,24 @@ unsigned int CCoreAudioAEStream::GetFrames(uint8_t *buffer, unsigned int size)
 #endif
       CAEUtil::ClampArray(floatBuffer, samples);
     }
+    // apply volume amplification by using the sogt limiter
+    // TODO - maybe reinvent the coreaudio compressor for this after frodo
+    else if (GetAmplification() != 1.0f)
+    {
+      for(unsigned int i = 0; i < frames; i++)
+      {
+        int frameIdx = i*m_chLayoutCountOutput;
+        float amplification = RunLimiter(&floatBuffer[frameIdx], m_chLayoutCountOutput);
+        float *frameStart = &floatBuffer[frameIdx];
+#ifdef __SSE___
+        CAEUtil::SSEMulArray(frameStart, amplification, m_chLayoutCountOutput);
+#else
+        for(unsigned int n = 0; n < m_chLayoutCountOutput; n++)
+          frameStart[n] *= amplification;
+#endif
+
+      }
+    }
   }
 
   return readsize;

diff --git a/xbmc/cores/AudioEngine/Engines/CoreAudio/CoreAudioAEStream.h b/xbmc/cores/AudioEngine/Engines/CoreAudio/CoreAudioAEStream.h
@@ -28,6 +28,7 @@
 #include "Interfaces/AEStream.h"
 #include "cores/AudioEngine/Utils/AEConvert.h"
 #include "cores/AudioEngine/Utils/AERemap.h"
+#include "Utils/AELimiter.h"
 
 #if defined(TARGET_DARWIN_IOS)
 # include "CoreAudioAEHALIOS.h"
@@ -77,8 +78,12 @@ class CCoreAudioAEStream : public IAEStream, public ICoreAudioSource
 
   virtual float GetVolume();
   virtual float GetReplayGain();
+  virtual float GetAmplification() { return m_limiter.GetAmplification(); }
   virtual void  SetVolume(float volume);
   virtual void  SetReplayGain(float factor);
+  virtual void  SetAmplification(float amplify){ m_limiter.SetAmplification(amplify); }
+
+  virtual float RunLimiter(float* frame, int channels) { return m_limiter.Run(frame, channels); }
 
   virtual const unsigned int      GetChannelCount() const;
   virtual const unsigned int      GetSampleRate() const;
@@ -129,6 +134,7 @@ class CCoreAudioAEStream : public IAEStream, public ICoreAudioSource
   CAERemap                m_remap;         /* the remapper */
   float                   m_volume;        /* the volume level */
   float                   m_rgain;         /* replay gain level */
+  CAELimiter              m_limiter;       /* volume amplification/limiter*/
   IAEStream               *m_slave;        /* slave aestream */
 
   CAEConvert::AEConvertToFn m_convertFn;