--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/peck_fft.h	Fri Sep 16 12:53:08 2011 +0200
@@ -0,0 +1,111 @@
+#ifndef PECK_FFT_H
+#define PECK_FFT_H
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+#include <string.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef USE_SIMD
+# include <xmmintrin.h>
+# define peck_fft_scalar __m128
+#define PECK_FFT_MALLOC(nbytes) _mm_malloc(nbytes,16)
+#define PECK_FFT_FREE _mm_free
+#else	
+#define PECK_FFT_MALLOC malloc
+#define PECK_FFT_FREE free
+#endif	
+
+
+#ifdef FIXED_POINT
+#include <sys/types.h>	
+# if (FIXED_POINT == 32)
+#  define peck_fft_scalar int32_t
+# else	
+#  define peck_fft_scalar int16_t
+# endif
+#else
+# ifndef peck_fft_scalar
+/*  default is float */
+#   define peck_fft_scalar float
+# endif
+#endif
+
+typedef struct {
+    peck_fft_scalar r;
+    peck_fft_scalar i;
+}peck_fft_cpx;
+
+typedef struct peck_fft_state* peck_fft_cfg;
+
+/* 
+ *  peck_fft_alloc
+ *  
+ *  Initialize a FFT (or IFFT) algorithm's cfg/state buffer.
+ *
+ *  typical usage:      peck_fft_cfg mycfg=peck_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 peck_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.
+ * */
+
+peck_fft_cfg peck_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem); 
+
+/*
+ * peck_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 peck_fft(peck_fft_cfg cfg,const peck_fft_cpx *fin,peck_fft_cpx *fout);
+
+/*
+ A more generic version of the above function. It reads its input from every Nth sample.
+ * */
+void peck_fft_stride(peck_fft_cfg cfg,const peck_fft_cpx *fin,peck_fft_cpx *fout,int fin_stride);
+
+/* If peck_fft_alloc allocated a buffer, it is one contiguous 
+   buffer and can be simply free()d when no longer needed*/
+#define peck_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 peck_fft_cleanup(void);
+	
+
+/*
+ * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5)
+ */
+int peck_fft_next_fast_size(int n);
+
+/* for real ffts, we need an even size */
+#define peck_fftr_next_fast_size_real(n) \
+        (peck_fft_next_fast_size( ((n)+1)>>1)<<1)
+
+#ifdef __cplusplus
+} 
+#endif
+
+#endif