dmlib: src/dmfft.c annotate

annotate src/dmfft.c @ 2294:7f6ba3b32f54

Cleanups.

author	Matti Hamalainen <ccr@tnsp.org>
date	Wed, 03 Jul 2019 10:28:43 +0300
parents	e68f7b0cb536
children	69a5af2eb1ea

rev	line source
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	1 /*
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	2 * Realfftf
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	3 * Originally (C) Copyright 1993 Philib Van Baren
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	4 * Cleaned up and refactored to be re-entrant by
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	5 * Matti 'ccr' Hamalainen <ccr@tnsp.org>, 2013
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	6 *
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	7 * Note: Output is BIT-REVERSED! so you must use the BitReversed to
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	8 * get legible output, (i.e. Real_i = buffer[ BitReversed[i] ]
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	9 * Imag_i = buffer[ BitReversed[i]+1 ] )
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	10 * Input is in normal order.
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	11 */
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	12 #include "dmfft.h"
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	13 #include <math.h>
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	14
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	15
1691 e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	16 #define DM_PW(a, b, c) (sqrt((a) * (a) + (b) * (b)) * (c))
e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	17
e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	18
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	19 int dmInitializeFFT(DMFFTContext * ctx, const int fftlen)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	20 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	21 if (ctx == NULL)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	22 return DMERR_NULLPTR;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	23
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	24 if (fftlen <= 16)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	25 return DMERR_INVALID_ARGS;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	26
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	27 // Allocate necessary tables
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	28 ctx->npoints = fftlen / 2;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	29 ctx->sinTable = (DMFFTType ) dmMalloc(fftlen sizeof(DMFFTType));
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	30 if (ctx->sinTable == NULL)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	31 return DMERR_MALLOC;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	32
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	33 // Bitreversion buffer
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	34 ctx->breversed = (int ) dmMalloc(ctx->npoints sizeof(int));
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	35 if (ctx->breversed == NULL)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	36 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	37 dmFree(ctx->sinTable);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	38 return DMERR_MALLOC;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	39 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	40
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	41 // Calculate data
1691 e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	42 for (int i = 0; i < ctx->npoints; i++)
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	43 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	44 int mask, tmp;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	45 for (tmp = 0, mask = ctx->npoints / 2; mask > 0; mask >>= 1)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	46 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	47 tmp = (tmp >> 1) + ((i & mask) ? ctx->npoints : 0);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	48 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	49
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	50 ctx->breversed[i] = tmp;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	51 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	52
1691 e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	53 for (int i = 0; i < ctx->npoints; i++)
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	54 {
751 817e792d9360 Use DM_PI instead of M_PI. Matti Hamalainen <ccr@tnsp.org> parents: 750 diff changeset	55 ctx->sinTable[ctx->breversed[i]] = -sin((2.0f * DM_PI * i) / fftlen);
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	56 ctx->sinTable[ctx->breversed[i] + 1] =
751 817e792d9360 Use DM_PI instead of M_PI. Matti Hamalainen <ccr@tnsp.org> parents: 750 diff changeset	57 -cos((2.0f * DM_PI * i) / fftlen);
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	58 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	59
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	60 return DMERR_OK;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	61 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	62
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	63
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	64 void dmEndFFT(DMFFTContext * ctx)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	65 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	66 if (ctx != NULL)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	67 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	68 dmFree(ctx->breversed);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	69 dmFree(ctx->sinTable);
1167 848a88ce7a57 Use dmMemset(). Matti Hamalainen <ccr@tnsp.org> parents: 1102 diff changeset	70 dmMemset(ctx, 0, sizeof(DMFFTContext));
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	71 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	72 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	73
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	74
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	75 int dmRealFFT(DMFFTContext * ctx, DMFFTType * buffer)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	76 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	77 if (ctx == NULL \|\| buffer == NULL)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	78 return DMERR_NULLPTR;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	79
1252 f077a709d491 Cleanup. Matti Hamalainen <ccr@tnsp.org> parents: 1167 diff changeset	80 const int *br1 = ctx->breversed + 1;
f077a709d491 Cleanup. Matti Hamalainen <ccr@tnsp.org> parents: 1167 diff changeset	81 const int *br2 = ctx->breversed + ctx->npoints - 1;
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	82 int rounds = ctx->npoints / 2;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	83 DMFFTType endptr1 = buffer + ctx->npoints 2;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	84
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	85 while (rounds > 0)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	86 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	87 DMFFTType *sptr = ctx->sinTable;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	88 DMFFTType *A = buffer,
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	89 B = buffer + rounds 2;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	90
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	91 while (A < endptr1)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	92 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	93 DMFFTType qsin = *sptr;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	94 DMFFTType qcos = *(sptr + 1);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	95 DMFFTType *endptr2 = B;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	96
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	97 while (A < endptr2)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	98 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	99 DMFFTType v1 = (B) qcos + ((B + 1)) qsin;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	100 DMFFTType v2 = (B) qsin - ((B + 1)) qcos;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	101 B = (A + v1) * 0.5;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	102 (A++) = (B++) - v1;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	103 B = (A - v2) * 0.5;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	104 (A++) = (B++) + v2;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	105 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	106 A = B;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	107 B += rounds * 2;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	108 sptr += 2;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	109 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	110
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	111 rounds >>= 1;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	112 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	113
1252 f077a709d491 Cleanup. Matti Hamalainen <ccr@tnsp.org> parents: 1167 diff changeset	114 // Massage output to get the output for a real input sequence.
749 44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	115 while (br1 <= br2)
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	116 {
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	117 const DMFFTType vsin = ctx->sinTable[*br1];
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	118 const DMFFTType vcos = ctx->sinTable[*br1 + 1];
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	119 DMFFTType A = buffer + br1,
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	120 B = buffer + br2,
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	121 HRplus, HRminus,
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	122 HIplus, HIminus,
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	123 tmp1, tmp2;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	124
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	125 HRminus = A - B;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	126 HRplus = HRminus + (B 2);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	127
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	128 HIminus = (A + 1) - (B + 1);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	129 HIplus = HIminus + ((B + 1) 2);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	130
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	131 tmp1 = (vsin * HRminus) - (vcos * HIplus);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	132 tmp2 = (vcos * HRminus) + (vsin * HIplus);
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	133
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	134 A = (HRplus + tmp1) 0.5f;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	135 B = A - tmp1;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	136
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	137 (A + 1) = (HIminus + tmp2) 0.5f;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	138 (B + 1) = ((A + 1)) - HIminus;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	139
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	140 br1++;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	141 br2--;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	142 }
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	143
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	144 // Handle DC bin separately
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	145 buffer[0] += buffer[1];
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	146 buffer[1] = 0;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	147
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	148 return DMERR_OK;
44138892c784 Add FFT routines. Matti Hamalainen <ccr@tnsp.org> parents: diff changeset	149 }
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	150
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	151
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	152 int dmConvertFFTtoFreqDomain(DMFFTContext ctx, DMFFTType buffer,
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	153 DMFFTType real, DMFFTType imag)
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	154 {
1691 e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	155 if (ctx == NULL \|\| buffer == NULL \|\|
e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	156 real == NULL \|\| imag == NULL)
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	157 return DMERR_NULLPTR;
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	158
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	159 // Convert from bitreversed form to normal frequency domain
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	160 const int *breversed = ctx->breversed;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	161
1691 e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	162 for (int i = 1; i < ctx->npoints; i++)
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	163 {
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	164 real[i] = buffer[breversed[i] ];
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	165 imag[i] = buffer[breversed[i]+1];
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	166 }
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	167
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	168 // Make the ends meet
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	169 real[0] = buffer[0];
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	170 imag[0] = 0;
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	171 real[ctx->npoints] = buffer[1];
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	172 imag[ctx->npoints] = 0;
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	173
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	174 return DMERR_OK;
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	175 }
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	176
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	177
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	178 int dmConvertFFTtoFreqAndPower(DMFFTContext ctx, DMFFTType buffer,
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	179 DMFFTType real, DMFFTType imag, DMFFTType *power, const DMFFTType scale)
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	180 {
1691 e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	181 if (ctx == NULL \|\| buffer == NULL \|\|
e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	182 real == NULL \|\| imag == NULL \|\| power == NULL)
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	183 return DMERR_NULLPTR;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	184
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	185 // Convert from bitreversed form to normal frequency domain
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	186 const int *breversed = ctx->breversed;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	187
1691 e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	188 for (int i = 1; i < ctx->npoints; i++)
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	189 {
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	190 DMFFTType fre = real[i] = buffer[breversed[i] ],
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	191 fim = imag[i] = buffer[breversed[i]+1];
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	192
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	193 power[i] = DM_PW(fre, fim, scale);
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	194 }
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	195
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	196 // Make the ends meet
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	197 real[0] = buffer[0];
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	198 imag[0] = 0;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	199 power[0] = DM_PW(buffer[0], 0, scale);
1102 e06abfde6c39 Cosmetics pass: Remove excess whitespace. Matti Hamalainen <ccr@tnsp.org> parents: 812 diff changeset	200
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	201 real[ctx->npoints] = buffer[1];
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	202 imag[ctx->npoints] = 0;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	203 power[ctx->npoints] = DM_PW(buffer[1], 0, scale);
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	204
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	205 return DMERR_OK;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	206 }
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	207
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	208
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	209 int dmConvertFFTtoPowerAndSum(DMFFTContext ctx, DMFFTType buffer,
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	210 DMFFTType power, const DMFFTType pscale, DMFFTType sum, const DMFFTType sscale)
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	211 {
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	212 if (ctx == NULL \|\| buffer == NULL \|\| power == NULL \|\| sum == NULL)
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	213 return DMERR_NULLPTR;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	214
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	215 // Convert from bitreversed form to normal frequency domain
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	216 const int *breversed = ctx->breversed;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	217 DMFFTType psum = 0;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	218
1691 e68f7b0cb536 Cleanups. Matti Hamalainen <ccr@tnsp.org> parents: 1252 diff changeset	219 for (int i = 1; i < ctx->npoints; i++)
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	220 {
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	221 DMFFTType fre = buffer[breversed[i] ],
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	222 fim = buffer[breversed[i]+1],
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	223 fpw = sqrt(fre * fre + fim * fim);
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	224
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	225 power[i] = fpw * pscale;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	226 psum += fpw * sscale;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	227 }
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	228
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	229 // Make the ends meet
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	230 power[0] = DM_PW(buffer[0], 0, pscale);
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	231 power[ctx->npoints] = DM_PW(buffer[1], 0, pscale);
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	232
773 95d9bd557a54 Return the power sum variable in the FFT conversion. Matti Hamalainen <ccr@tnsp.org> parents: 772 diff changeset	233 *sum = psum;
95d9bd557a54 Return the power sum variable in the FFT conversion. Matti Hamalainen <ccr@tnsp.org> parents: 772 diff changeset	234
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	235 return DMERR_OK;
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	236 }
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	237
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	238
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	239 int dmConvertFFTtoTimeDomain(DMFFTContext ctx, DMFFTType buffer, DMFFTType *tdom)
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	240 {
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	241 int i, n;
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	242 if (ctx == NULL \|\| buffer == NULL \|\| tdom == NULL)
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	243 return DMERR_NULLPTR;
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	244
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	245 for (n = i = 0; i < ctx->npoints; i++, n += 2)
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	246 {
772 59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	247 tdom[n ] = buffer[ctx->breversed[i] ];
59df354b99cc Add some utility functions in the FFT module. Matti Hamalainen <ccr@tnsp.org> parents: 751 diff changeset	248 tdom[n+1] = buffer[ctx->breversed[i]+1];
750 e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	249 }
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	250
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	251 return DMERR_OK;
e6d807ce715b Add two more functions for converting FFT data to frequency and time Matti Hamalainen <ccr@tnsp.org> parents: 749 diff changeset	252 }

Mercurial > hg > dmlib

annotate src/dmfft.c @ 2294:7f6ba3b32f54