1 /*

     2 * Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description: 

    15 *

    16 */

    17 #ifndef KISS_FFT_S16_H

    18 #define KISS_FFT_S16_H

    19 

    20 #include <stdlib.h>

    21 #include <stdio.h>

    22 #include <math.h>

    23 #include <memory.h>

    24 #include <glib.h>

    25 

    26 #ifdef __cplusplus

    27 extern "C" {

    28 #endif

    29 

    30 /*

    31  ATTENTION!

    32  If you would like a :

    33  -- a utility that will handle the caching of fft objects

    34  -- real-only (no imaginary time component ) FFT

    35  -- a multi-dimensional FFT

    36  -- a command-line utility to perform ffts

    37  -- a command-line utility to perform fast-convolution filtering

    38 

    39  Then see kfc.h kiss_fftr.h kiss_fftnd.h fftutil.c kiss_fastfir.c

    40   in the tools/ directory.

    41 */

    42 

    43 #define KISS_FFT_S16_MALLOC g_malloc

    44 

    45 #include "machine/_stdint.h"

    46 

    47 #define kiss_fft_s16_scalar int16_t

    48 

    49 typedef struct {

    50     kiss_fft_s16_scalar r;

    51     kiss_fft_s16_scalar i;

    52 }kiss_fft_s16_cpx;

    53 

    54 typedef struct kiss_fft_s16_state* kiss_fft_s16_cfg;

    55 

    56 /* 

    57  *  kiss_fft_s16_alloc

    58  *  

    59  *  Initialize a FFT (or IFFT) algorithm's cfg/state buffer.

    60  *

    61  *  typical usage:      kiss_fft_s16_cfg mycfg=kiss_fft_s16_alloc(1024,0,NULL,NULL);

    62  *

    63  *  The return value from fft_alloc is a cfg buffer used internally

    64  *  by the fft routine or NULL.

    65  *

    66  *  If lenmem is NULL, then kiss_fft_s16_alloc will allocate a cfg buffer using malloc.

    67  *  The returned value should be free()d when done to avoid memory leaks.

    68  *  

    69  *  The state can be placed in a user supplied buffer 'mem':

    70  *  If lenmem is not NULL and mem is not NULL and *lenmem is large enough,

    71  *      then the function places the cfg in mem and the size used in *lenmem

    72  *      and returns mem.

    73  *  

    74  *  If lenmem is not NULL and ( mem is NULL or *lenmem is not large enough),

    75  *      then the function returns NULL and places the minimum cfg 

    76  *      buffer size in *lenmem.

    77  * */

    78 #ifdef __SYMBIAN32__

    79 IMPORT_C

    80 #endif

    81 

    82 

    83 kiss_fft_s16_cfg kiss_fft_s16_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem); 

    84 

    85 /*

    86  * kiss_fft(cfg,in_out_buf)

    87  *

    88  * Perform an FFT on a complex input buffer.

    89  * for a forward FFT,

    90  * fin should be  f[0] , f[1] , ... ,f[nfft-1]

    91  * fout will be   F[0] , F[1] , ... ,F[nfft-1]

    92  * Note that each element is complex and can be accessed like

    93     f[k].r and f[k].i

    94  * */

    95 #ifdef __SYMBIAN32__

    96 IMPORT_C

    97 #endif

    98 

    99 void kiss_fft_s16(kiss_fft_s16_cfg cfg,const kiss_fft_s16_cpx *fin,kiss_fft_s16_cpx *fout);

   100 

   101 /*

   102  A more generic version of the above function. It reads its input from every Nth sample.

   103  * */

   104 #ifdef __SYMBIAN32__

   105 IMPORT_C

   106 #endif

   107 

   108 void kiss_fft_s16_stride(kiss_fft_s16_cfg cfg,const kiss_fft_s16_cpx *fin,kiss_fft_s16_cpx *fout,int fin_stride);

   109 

   110 /* If kiss_fft_s16_alloc allocated a buffer, it is one contiguous 

   111    buffer and can be simply free()d when no longer needed*/

   112 #define kiss_fft_s16_free g_free

   113 

   114 /*

   115  Cleans up some memory that gets managed internally. Not necessary to call, but it might clean up 

   116  your compiler output to call this before you exit.

   117 */

   118 #ifdef __SYMBIAN32__

   119 IMPORT_C

   120 #endif

   121 

   122 void kiss_fft_s16_cleanup(void);

   123 	

   124 

   125 /*

   126  * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5)

   127  */

   128 #ifdef __SYMBIAN32__

   129 IMPORT_C

   130 #endif

   131 

   132 int kiss_fft_s16_next_fast_size(int n);

   133 

   134 #ifdef __cplusplus

   135 } 

   136 #endif

   137 

   138 #endif