libs/soundtouch/FIRFilter.h

   1 ////////////////////////////////////////////////////////////////////////////////
   2 ///
   3 /// General FIR digital filter routines with MMX optimization.
   4 ///
   5 /// Note : MMX optimized functions reside in a separate, platform-specific file,
   6 /// e.g. 'mmx_win.cpp' or 'mmx_gcc.cpp'
   7 ///
   8 /// Author        : Copyright (c) Olli Parviainen
   9 /// Author e-mail : oparviai @ iki.fi
  10 /// SoundTouch WWW: http://www.iki.fi/oparviai/soundtouch
  11 ///
  12 ////////////////////////////////////////////////////////////////////////////////
  13 //
  14 // Last changed  : $Date$
  15 // File revision : $Revision$
  16 //
  17 // $Id$
  18 //
  19 ////////////////////////////////////////////////////////////////////////////////
  20 //
  21 // License :
  22 //
  23 //  SoundTouch audio processing library
  24 //  Copyright (c) Olli Parviainen
  25 //
  26 //  This library is free software; you can redistribute it and/or
  27 //  modify it under the terms of the GNU Lesser General Public
  28 //  License as published by the Free Software Foundation; either
  29 //  version 2.1 of the License, or (at your option) any later version.
  30 //
  31 //  This library is distributed in the hope that it will be useful,
  32 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  33 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  34 //  Lesser General Public License for more details.
  35 //
  36 //  You should have received a copy of the GNU Lesser General Public
  37 //  License along with this library; if not, write to the Free Software
  38 //  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  39 //
  40 ////////////////////////////////////////////////////////////////////////////////
  41
  42 #ifndef FIRFilter_H
  43 #define FIRFilter_H
  44
  45 #include "STTypes.h"
  46
  47 namespace soundtouch
  48 {
  49
  50 class FIRFilter
  51 {
  52 protected:
  53     // Number of FIR filter taps
  54     uint length;
  55     // Number of FIR filter taps divided by 8
  56     uint lengthDiv8;
  57
  58     // Result divider factor in 2^k format
  59     uint resultDivFactor;
  60
  61     // Result divider value.
  62     SAMPLETYPE resultDivider;
  63
  64     // Memory for filter coefficients
  65     SAMPLETYPE *filterCoeffs;
  66
  67     virtual uint evaluateFilterStereo(SAMPLETYPE *dest,
  68                                       const SAMPLETYPE *src,
  69                                       uint numSamples) const;
  70     virtual uint evaluateFilterMono(SAMPLETYPE *dest,
  71                                     const SAMPLETYPE *src,
  72                                     uint numSamples) const;
  73
  74     FIRFilter();
  75
  76 public:
  77     virtual ~FIRFilter();
  78
  79     static FIRFilter *newInstance();
  80
  81     /// Applies the filter to the given sequence of samples.
  82     /// Note : The amount of outputted samples is by value of 'filter_length'
  83     /// smaller than the amount of input samples.
  84     ///
  85     /// \return Number of samples copied to 'dest'.
  86     uint evaluate(SAMPLETYPE *dest,
  87                   const SAMPLETYPE *src,
  88                   uint numSamples,
  89                   uint numChannels) const;
  90
  91     uint getLength() const;
  92
  93     virtual void setCoefficients(const SAMPLETYPE *coeffs,
  94                                  uint newLength,
  95                                  uint uResultDivFactor);
  96 };
  97
  98
  99 // Optional subclasses that implement CPU-specific optimizations:
 100
 101 #ifdef ALLOW_MMX
 102
 103     /// Class that implements MMX optimized functions exclusive for 16bit integer samples type.
 104     class FIRFilterMMX : public FIRFilter
 105     {
 106     protected:
 107         short *filterCoeffsUnalign;
 108         short *filterCoeffsAlign;
 109
 110         virtual uint evaluateFilterStereo(short *dest, const short *src, uint numSamples) const;
 111     public:
 112         FIRFilterMMX();
 113         ~FIRFilterMMX();
 114
 115         virtual void setCoefficients(const short *coeffs, uint newLength, uint uResultDivFactor);
 116     };
 117
 118 #endif // ALLOW_MMX
 119
 120
 121 #ifdef ALLOW_3DNOW
 122
 123     /// Class that implements 3DNow! optimized functions exclusive for floating point samples type.
 124     class FIRFilter3DNow : public FIRFilter
 125     {
 126     protected:
 127         float *filterCoeffsUnalign;
 128         float *filterCoeffsAlign;
 129
 130         virtual uint evaluateFilterStereo(float *dest, const float *src, uint numSamples) const;
 131     public:
 132         FIRFilter3DNow();
 133         ~FIRFilter3DNow();
 134         virtual void setCoefficients(const float *coeffs, uint newLength, uint uResultDivFactor);
 135     };
 136
 137 #endif  // ALLOW_3DNOW
 138
 139
 140 #ifdef ALLOW_SSE
 141     /// Class that implements SSE optimized functions exclusive for floating point samples type.
 142     class FIRFilterSSE : public FIRFilter
 143     {
 144     protected:
 145         float *filterCoeffsUnalign;
 146         float *filterCoeffsAlign;
 147
 148         virtual uint evaluateFilterStereo(float *dest, const float *src, uint numSamples) const;
 149     public:
 150         FIRFilterSSE();
 151         ~FIRFilterSSE();
 152
 153         virtual void setCoefficients(const float *coeffs, uint newLength, uint uResultDivFactor);
 154     };
 155
 156 #endif // ALLOW_SSE
 157
 158 }
 159
 160 #endif  // FIRFilter_H