_kiss_fft_guts.h (5260B)
1 /* 2 Copyright (c) 2003-2004, Mark Borgerding 3 4 All rights reserved. 5 6 Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 7 8 * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 9 * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 10 * Neither the author nor the names of any contributors may be used to endorse or promote products derived from this software without specific prior written permission. 11 12 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 13 */ 14 15 /* kiss_fft.h 16 defines kiss_fft_scalar as either short or a float type 17 and defines 18 typedef struct { kiss_fft_scalar r; kiss_fft_scalar i; }kiss_fft_cpx; */ 19 #include "kiss_fft.h" 20 #include <limits.h> 21 22 #define MAXFACTORS 32 23 /* e.g. an fft of length 128 has 4 factors 24 as far as kissfft is concerned 25 4*4*4*2 26 */ 27 28 struct kiss_fft_state{ 29 int nfft; 30 int inverse; 31 int factors[2*MAXFACTORS]; 32 kiss_fft_cpx twiddles[1]; 33 }; 34 35 /* 36 Explanation of macros dealing with complex math: 37 38 C_MUL(m,a,b) : m = a*b 39 C_FIXDIV( c , div ) : if a fixed point impl., c /= div. noop otherwise 40 C_SUB( res, a,b) : res = a - b 41 C_SUBFROM( res , a) : res -= a 42 C_ADDTO( res , a) : res += a 43 * */ 44 #ifdef FIXED_POINT 45 #if (FIXED_POINT==32) 46 # define FRACBITS 31 47 # define SAMPPROD int64_t 48 #define SAMP_MAX 2147483647 49 #else 50 # define FRACBITS 15 51 # define SAMPPROD int32_t 52 #define SAMP_MAX 32767 53 #endif 54 55 #define SAMP_MIN -SAMP_MAX 56 57 #if defined(CHECK_OVERFLOW) 58 # define CHECK_OVERFLOW_OP(a,op,b) \ 59 if ( (SAMPPROD)(a) op (SAMPPROD)(b) > SAMP_MAX || (SAMPPROD)(a) op (SAMPPROD)(b) < SAMP_MIN ) { \ 60 fprintf(stderr,"WARNING:overflow @ " __FILE__ "(%d): (%d " #op" %d) = %ld\n",__LINE__,(a),(b),(SAMPPROD)(a) op (SAMPPROD)(b) ); } 61 #endif 62 63 64 # define smul(a,b) ( (SAMPPROD)(a)*(b) ) 65 # define sround( x ) (kiss_fft_scalar)( ( (x) + (1<<(FRACBITS-1)) ) >> FRACBITS ) 66 67 # define S_MUL(a,b) sround( smul(a,b) ) 68 69 # define C_MUL(m,a,b) \ 70 do{ (m).r = sround( smul((a).r,(b).r) - smul((a).i,(b).i) ); \ 71 (m).i = sround( smul((a).r,(b).i) + smul((a).i,(b).r) ); }while(0) 72 73 # define DIVSCALAR(x,k) \ 74 (x) = sround( smul( x, SAMP_MAX/k ) ) 75 76 # define C_FIXDIV(c,div) \ 77 do { DIVSCALAR( (c).r , div); \ 78 DIVSCALAR( (c).i , div); }while (0) 79 80 # define C_MULBYSCALAR( c, s ) \ 81 do{ (c).r = sround( smul( (c).r , s ) ) ;\ 82 (c).i = sround( smul( (c).i , s ) ) ; }while(0) 83 84 #else /* not FIXED_POINT*/ 85 86 # define S_MUL(a,b) ( (a)*(b) ) 87 #define C_MUL(m,a,b) \ 88 do{ (m).r = (a).r*(b).r - (a).i*(b).i;\ 89 (m).i = (a).r*(b).i + (a).i*(b).r; }while(0) 90 # define C_FIXDIV(c,div) /* NOOP */ 91 # define C_MULBYSCALAR( c, s ) \ 92 do{ (c).r *= (s);\ 93 (c).i *= (s); }while(0) 94 #endif 95 96 #ifndef CHECK_OVERFLOW_OP 97 # define CHECK_OVERFLOW_OP(a,op,b) /* noop */ 98 #endif 99 100 #define C_ADD( res, a,b)\ 101 do { \ 102 CHECK_OVERFLOW_OP((a).r,+,(b).r)\ 103 CHECK_OVERFLOW_OP((a).i,+,(b).i)\ 104 (res).r=(a).r+(b).r; (res).i=(a).i+(b).i; \ 105 }while(0) 106 #define C_SUB( res, a,b)\ 107 do { \ 108 CHECK_OVERFLOW_OP((a).r,-,(b).r)\ 109 CHECK_OVERFLOW_OP((a).i,-,(b).i)\ 110 (res).r=(a).r-(b).r; (res).i=(a).i-(b).i; \ 111 }while(0) 112 #define C_ADDTO( res , a)\ 113 do { \ 114 CHECK_OVERFLOW_OP((res).r,+,(a).r)\ 115 CHECK_OVERFLOW_OP((res).i,+,(a).i)\ 116 (res).r += (a).r; (res).i += (a).i;\ 117 }while(0) 118 119 #define C_SUBFROM( res , a)\ 120 do {\ 121 CHECK_OVERFLOW_OP((res).r,-,(a).r)\ 122 CHECK_OVERFLOW_OP((res).i,-,(a).i)\ 123 (res).r -= (a).r; (res).i -= (a).i; \ 124 }while(0) 125 126 127 #ifdef FIXED_POINT 128 # define KISS_FFT_COS(phase) floor(.5+SAMP_MAX * cos (phase)) 129 # define KISS_FFT_SIN(phase) floor(.5+SAMP_MAX * sin (phase)) 130 # define HALF_OF(x) ((x)>>1) 131 #elif defined(USE_SIMD) 132 # define KISS_FFT_COS(phase) _mm_set1_ps( cos(phase) ) 133 # define KISS_FFT_SIN(phase) _mm_set1_ps( sin(phase) ) 134 # define HALF_OF(x) ((x)*_mm_set1_ps(.5)) 135 #else 136 # define KISS_FFT_COS(phase) (kiss_fft_scalar) cos(phase) 137 # define KISS_FFT_SIN(phase) (kiss_fft_scalar) sin(phase) 138 # define HALF_OF(x) ((x)*.5) 139 #endif 140 141 #define kf_cexp(x,phase) \ 142 do{ \ 143 (x)->r = KISS_FFT_COS(phase);\ 144 (x)->i = KISS_FFT_SIN(phase);\ 145 }while(0) 146 147 148 /* a debugging function */ 149 #define pcpx(c)\ 150 fprintf(stderr,"%g + %gi\n",(double)((c)->r),(double)((c)->i) )