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-rw-r--r--media/kiss_fft/kiss_fft.h124
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diff --git a/media/kiss_fft/kiss_fft.h b/media/kiss_fft/kiss_fft.h
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+++ b/media/kiss_fft/kiss_fft.h
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+#ifndef KISS_FFT_H
+#define KISS_FFT_H
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+#include <string.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ ATTENTION!
+ If you would like a :
+ -- a utility that will handle the caching of fft objects
+ -- real-only (no imaginary time component ) FFT
+ -- a multi-dimensional FFT
+ -- a command-line utility to perform ffts
+ -- a command-line utility to perform fast-convolution filtering
+
+ Then see kfc.h kiss_fftr.h kiss_fftnd.h fftutil.c kiss_fastfir.c
+ in the tools/ directory.
+*/
+
+#ifdef USE_SIMD
+# include <xmmintrin.h>
+# define kiss_fft_scalar __m128
+#define KISS_FFT_MALLOC(nbytes) _mm_malloc(nbytes,16)
+#define KISS_FFT_FREE _mm_free
+#else
+#define KISS_FFT_MALLOC malloc
+#define KISS_FFT_FREE free
+#endif
+
+
+#ifdef FIXED_POINT
+#include <sys/types.h>
+# if (FIXED_POINT == 32)
+# define kiss_fft_scalar int32_t
+# else
+# define kiss_fft_scalar int16_t
+# endif
+#else
+# ifndef kiss_fft_scalar
+/* default is float */
+# define kiss_fft_scalar float
+# endif
+#endif
+
+typedef struct {
+ kiss_fft_scalar r;
+ kiss_fft_scalar i;
+}kiss_fft_cpx;
+
+typedef struct kiss_fft_state* kiss_fft_cfg;
+
+/*
+ * kiss_fft_alloc
+ *
+ * Initialize a FFT (or IFFT) algorithm's cfg/state buffer.
+ *
+ * typical usage: kiss_fft_cfg mycfg=kiss_fft_alloc(1024,0,NULL,NULL);
+ *
+ * The return value from fft_alloc is a cfg buffer used internally
+ * by the fft routine or NULL.
+ *
+ * If lenmem is NULL, then kiss_fft_alloc will allocate a cfg buffer using malloc.
+ * The returned value should be free()d when done to avoid memory leaks.
+ *
+ * The state can be placed in a user supplied buffer 'mem':
+ * If lenmem is not NULL and mem is not NULL and *lenmem is large enough,
+ * then the function places the cfg in mem and the size used in *lenmem
+ * and returns mem.
+ *
+ * If lenmem is not NULL and ( mem is NULL or *lenmem is not large enough),
+ * then the function returns NULL and places the minimum cfg
+ * buffer size in *lenmem.
+ * */
+
+kiss_fft_cfg kiss_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem);
+
+/*
+ * kiss_fft(cfg,in_out_buf)
+ *
+ * Perform an FFT on a complex input buffer.
+ * for a forward FFT,
+ * fin should be f[0] , f[1] , ... ,f[nfft-1]
+ * fout will be F[0] , F[1] , ... ,F[nfft-1]
+ * Note that each element is complex and can be accessed like
+ f[k].r and f[k].i
+ * */
+void kiss_fft(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout);
+
+/*
+ A more generic version of the above function. It reads its input from every Nth sample.
+ * */
+void kiss_fft_stride(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout,int fin_stride);
+
+/* If kiss_fft_alloc allocated a buffer, it is one contiguous
+ buffer and can be simply free()d when no longer needed*/
+#define kiss_fft_free free
+
+/*
+ Cleans up some memory that gets managed internally. Not necessary to call, but it might clean up
+ your compiler output to call this before you exit.
+*/
+void kiss_fft_cleanup(void);
+
+
+/*
+ * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5)
+ */
+int kiss_fft_next_fast_size(int n);
+
+/* for real ffts, we need an even size */
+#define kiss_fftr_next_fast_size_real(n) \
+ (kiss_fft_next_fast_size( ((n)+1)>>1)<<1)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif