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author | erdgeist@erdgeist.org <erdgeist@bauklotz.fritz.box> | 2019-07-04 23:26:09 +0200 |
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committer | erdgeist@erdgeist.org <erdgeist@bauklotz.fritz.box> | 2019-07-04 23:26:09 +0200 |
commit | f02dfce6e6c34b3d8a7b8a0e784b506178e331fa (patch) | |
tree | 45556e6104242d4702689760433d7321ae74ec17 /kiss_fft.h |
stripdown of version 0.9
Diffstat (limited to 'kiss_fft.h')
-rw-r--r-- | kiss_fft.h | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/kiss_fft.h b/kiss_fft.h new file mode 100644 index 0000000..c01722c --- /dev/null +++ b/kiss_fft.h | |||
@@ -0,0 +1,124 @@ | |||
1 | #ifndef KISS_FFT_H | ||
2 | #define KISS_FFT_H | ||
3 | |||
4 | #include <stdlib.h> | ||
5 | #include <stdio.h> | ||
6 | #include <math.h> | ||
7 | #include <string.h> | ||
8 | |||
9 | #ifdef __cplusplus | ||
10 | extern "C" { | ||
11 | #endif | ||
12 | |||
13 | /* | ||
14 | ATTENTION! | ||
15 | If you would like a : | ||
16 | -- a utility that will handle the caching of fft objects | ||
17 | -- real-only (no imaginary time component ) FFT | ||
18 | -- a multi-dimensional FFT | ||
19 | -- a command-line utility to perform ffts | ||
20 | -- a command-line utility to perform fast-convolution filtering | ||
21 | |||
22 | Then see kfc.h kiss_fftr.h kiss_fftnd.h fftutil.c kiss_fastfir.c | ||
23 | in the tools/ directory. | ||
24 | */ | ||
25 | |||
26 | #ifdef USE_SIMD | ||
27 | # include <xmmintrin.h> | ||
28 | # define kiss_fft_scalar __m128 | ||
29 | #define KISS_FFT_MALLOC(nbytes) _mm_malloc(nbytes,16) | ||
30 | #define KISS_FFT_FREE _mm_free | ||
31 | #else | ||
32 | #define KISS_FFT_MALLOC malloc | ||
33 | #define KISS_FFT_FREE free | ||
34 | #endif | ||
35 | |||
36 | |||
37 | #ifdef FIXED_POINT | ||
38 | #include <sys/types.h> | ||
39 | # if (FIXED_POINT == 32) | ||
40 | # define kiss_fft_scalar int32_t | ||
41 | # else | ||
42 | # define kiss_fft_scalar int16_t | ||
43 | # endif | ||
44 | #else | ||
45 | # ifndef kiss_fft_scalar | ||
46 | /* default is float */ | ||
47 | # define kiss_fft_scalar float | ||
48 | # endif | ||
49 | #endif | ||
50 | |||
51 | typedef struct { | ||
52 | kiss_fft_scalar r; | ||
53 | kiss_fft_scalar i; | ||
54 | }kiss_fft_cpx; | ||
55 | |||
56 | typedef struct kiss_fft_state* kiss_fft_cfg; | ||
57 | |||
58 | /* | ||
59 | * kiss_fft_alloc | ||
60 | * | ||
61 | * Initialize a FFT (or IFFT) algorithm's cfg/state buffer. | ||
62 | * | ||
63 | * typical usage: kiss_fft_cfg mycfg=kiss_fft_alloc(1024,0,NULL,NULL); | ||
64 | * | ||
65 | * The return value from fft_alloc is a cfg buffer used internally | ||
66 | * by the fft routine or NULL. | ||
67 | * | ||
68 | * If lenmem is NULL, then kiss_fft_alloc will allocate a cfg buffer using malloc. | ||
69 | * The returned value should be free()d when done to avoid memory leaks. | ||
70 | * | ||
71 | * The state can be placed in a user supplied buffer 'mem': | ||
72 | * If lenmem is not NULL and mem is not NULL and *lenmem is large enough, | ||
73 | * then the function places the cfg in mem and the size used in *lenmem | ||
74 | * and returns mem. | ||
75 | * | ||
76 | * If lenmem is not NULL and ( mem is NULL or *lenmem is not large enough), | ||
77 | * then the function returns NULL and places the minimum cfg | ||
78 | * buffer size in *lenmem. | ||
79 | * */ | ||
80 | |||
81 | kiss_fft_cfg kiss_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem); | ||
82 | |||
83 | /* | ||
84 | * kiss_fft(cfg,in_out_buf) | ||
85 | * | ||
86 | * Perform an FFT on a complex input buffer. | ||
87 | * for a forward FFT, | ||
88 | * fin should be f[0] , f[1] , ... ,f[nfft-1] | ||
89 | * fout will be F[0] , F[1] , ... ,F[nfft-1] | ||
90 | * Note that each element is complex and can be accessed like | ||
91 | f[k].r and f[k].i | ||
92 | * */ | ||
93 | void kiss_fft(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout); | ||
94 | |||
95 | /* | ||
96 | A more generic version of the above function. It reads its input from every Nth sample. | ||
97 | * */ | ||
98 | void kiss_fft_stride(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout,int fin_stride); | ||
99 | |||
100 | /* If kiss_fft_alloc allocated a buffer, it is one contiguous | ||
101 | buffer and can be simply free()d when no longer needed*/ | ||
102 | #define kiss_fft_free free | ||
103 | |||
104 | /* | ||
105 | Cleans up some memory that gets managed internally. Not necessary to call, but it might clean up | ||
106 | your compiler output to call this before you exit. | ||
107 | */ | ||
108 | void kiss_fft_cleanup(void); | ||
109 | |||
110 | |||
111 | /* | ||
112 | * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5) | ||
113 | */ | ||
114 | int kiss_fft_next_fast_size(int n); | ||
115 | |||
116 | /* for real ffts, we need an even size */ | ||
117 | #define kiss_fftr_next_fast_size_real(n) \ | ||
118 | (kiss_fft_next_fast_size( ((n)+1)>>1)<<1) | ||
119 | |||
120 | #ifdef __cplusplus | ||
121 | } | ||
122 | #endif | ||
123 | |||
124 | #endif | ||