add oversampler

oversampling/WDL/convoengine.h

@@ -0,0 +1,179 @@
+/*
+  WDL - convoengine.h
+  Copyright (C) 2006 and later Cockos Incorporated
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+  
+
+  This file provides an interface to the WDL fast convolution engine. This engine can convolve audio streams using
+  either brute force (for small impulses), or a partitioned FFT scheme (for larger impulses). 
+
+  Note that this library needs to have lookahead ability in order to process samples. Calling Add(somevalue) may produce Avail() < somevalue.
+
+*/
+
+
+#ifndef _WDL_CONVOENGINE_H_
+#define _WDL_CONVOENGINE_H_
+
+#include "queue.h"
+#include "fastqueue.h"
+#include "fft.h"
+
+//#define WDL_CONVO_WANT_FULLPRECISION_IMPULSE_STORAGE // define this for slowerness with -138dB error difference in resulting output (+-1 LSB at 24 bit)
+
+#ifdef WDL_CONVO_WANT_FULLPRECISION_IMPULSE_STORAGE 
+
+typedef WDL_FFT_REAL WDL_CONVO_IMPULSEBUFf;
+typedef WDL_FFT_COMPLEX WDL_CONVO_IMPULSEBUFCPLXf;
+
+#else
+typedef float WDL_CONVO_IMPULSEBUFf;
+typedef struct
+{
+  WDL_CONVO_IMPULSEBUFf re, im;
+}
+WDL_CONVO_IMPULSEBUFCPLXf;
+#endif
+
+class WDL_ImpulseBuffer
+{
+public:
+  WDL_ImpulseBuffer()
+  {
+    samplerate=44100.0;
+    impulses.list.Add(new WDL_TypedBuf<WDL_FFT_REAL>);
+  }
+  ~WDL_ImpulseBuffer()
+  {
+    impulses.list.Empty(true);
+  }
+
+  int GetLength() { return impulses.list.GetSize() ? impulses[0].GetSize() : 0; }
+  int SetLength(int samples); // resizes/clears all channels accordingly, returns actual size set (can be 0 if error)
+  void SetNumChannels(int usench, bool duplicateExisting=true); // handles allocating/converting/etc
+  int GetNumChannels() { return impulses.list.GetSize(); }
+
+  double samplerate;
+  struct  {
+    WDL_PtrList<WDL_TypedBuf<WDL_FFT_REAL>  > list;
+
+    WDL_TypedBuf<WDL_FFT_REAL> &operator[](size_t i) const
+    {
+      WDL_TypedBuf<WDL_FFT_REAL> *p = list.Get(i);
+      if (WDL_NORMALLY(p != NULL)) return *p;
+      return *list.Get(0); // if for some reason an out of range index was passed, return first item rather than crash
+    }
+  } impulses;
+
+};
+
+class WDL_ConvolutionEngine
+{
+public:
+  WDL_ConvolutionEngine();
+  ~WDL_ConvolutionEngine();
+
+  int SetImpulse(WDL_ImpulseBuffer *impulse, int fft_size=-1, int impulse_sample_offset=0, int max_imp_size=0, bool forceBrute=false);
+ 
+  int GetFFTSize() { return m_fft_size; }
+  int GetLatency() { return m_fft_size/2; }
+  
+  void Reset(); // clears out any latent samples
+
+  void Add(WDL_FFT_REAL **bufs, int len, int nch);
+
+  int Avail(int wantSamples);
+  WDL_FFT_REAL **Get(); // returns length valid
+  void Advance(int len);
+
+private:
+
+  struct ImpChannelInfo {
+    WDL_TypedBuf<WDL_CONVO_IMPULSEBUFf> imp;
+    WDL_TypedBuf<char> zflag;
+  };
+
+  struct ProcChannelInfo {
+    WDL_Queue samplesout;
+    WDL_Queue samplesin2;
+    WDL_FastQueue samplesin;
+
+    WDL_TypedBuf<WDL_FFT_REAL> samplehist; // FFT'd sample blocks per channel
+    WDL_TypedBuf<char> samplehist_zflag;
+    WDL_TypedBuf<WDL_FFT_REAL> overlaphist;
+
+    int hist_pos;
+  };
+
+
+  WDL_PtrList<ImpChannelInfo> m_impdata;
+
+  int m_impulse_len;
+  int m_fft_size;
+
+  int m_proc_nch;
+  WDL_PtrList<ProcChannelInfo> m_proc;
+
+
+  WDL_TypedBuf<WDL_FFT_REAL> m_combinebuf;
+  WDL_TypedBuf<WDL_FFT_REAL *> m_get_tmpptrs;
+
+public:
+
+  // _div stuff
+  int m_zl_delaypos;
+  int m_zl_dumpage;
+
+//#define WDLCONVO_ZL_ACCOUNTING
+#ifdef WDLCONVO_ZL_ACCOUNTING
+  int m_zl_fftcnt;//removeme (testing of benchmarks)
+#endif
+  void AddSilenceToOutput(int len);
+
+} WDL_FIXALIGN;
+
+// low latency version
+class WDL_ConvolutionEngine_Div
+{
+public:
+  WDL_ConvolutionEngine_Div();
+  ~WDL_ConvolutionEngine_Div();
+
+  int SetImpulse(WDL_ImpulseBuffer *impulse, int maxfft_size=0, int known_blocksize=0, int max_imp_size=0, int impulse_offset=0, int latency_allowed=0);
+
+  int GetLatency();
+  void Reset();
+
+  void Add(WDL_FFT_REAL **bufs, int len, int nch);
+
+  int Avail(int wantSamples);
+  WDL_FFT_REAL **Get(); // returns length valid
+  void Advance(int len);
+
+private:
+  WDL_PtrList<WDL_ConvolutionEngine> m_engines;
+
+  WDL_PtrList<WDL_Queue> m_sout;
+  WDL_TypedBuf<WDL_FFT_REAL *> m_get_tmpptrs;
+
+  bool m_need_feedsilence;
+
+} WDL_FIXALIGN;
+
+
+#endif