[xiph-commits] r12055 - trunk/speex/libspeex

[jm at svn.xiph.org]

Author: jm
Date: 2006-11-07 07:02:52 -0800 (Tue, 07 Nov 2006)
New Revision: 12055

Modified:
   trunk/speex/libspeex/_kiss_fft_guts.h
   trunk/speex/libspeex/kiss_fft.c
   trunk/speex/libspeex/kiss_fftr.c
Log:
kissfft initialisation no longer uses any float operation. I think
the whole echo canceller+preprocessor are 100% float-free.


Modified: trunk/speex/libspeex/_kiss_fft_guts.h
===================================================================
--- trunk/speex/libspeex/_kiss_fft_guts.h	2006-11-07 13:25:33 UTC (rev 12054)
+++ trunk/speex/libspeex/_kiss_fft_guts.h	2006-11-07 15:02:52 UTC (rev 12055)
@@ -20,6 +20,7 @@
    and defines
    typedef struct { kiss_fft_scalar r; kiss_fft_scalar i; }kiss_fft_cpx; */
 #include "kiss_fft.h"
+#include "math_approx.h"
 
 #define MAXFACTORS 32
 /* e.g. an fft of length 128 has 4 factors 
@@ -140,6 +141,11 @@
 		(x)->r = KISS_FFT_COS(phase);\
 		(x)->i = KISS_FFT_SIN(phase);\
 	}while(0)
+#define  kf_cexp2(x,phase) \
+               do{ \
+               (x)->r = spx_cos_norm((phase));\
+               (x)->i = spx_cos_norm((phase)-32768);\
+}while(0)
 
 
 /* a debugging function */

Modified: trunk/speex/libspeex/kiss_fft.c
===================================================================
--- trunk/speex/libspeex/kiss_fft.c	2006-11-07 13:25:33 UTC (rev 12054)
+++ trunk/speex/libspeex/kiss_fft.c	2006-11-07 15:02:52 UTC (rev 12055)
@@ -338,8 +338,6 @@
 void kf_factor(int n,int * facbuf)
 {
     int p=4;
-    double floor_sqrt;
-    floor_sqrt = floor( sqrt((double)n) );
 
     /*factor out powers of 4, powers of 2, then any remaining primes */
     do {
@@ -349,7 +347,7 @@
                 case 2: p = 3; break;
                 default: p += 2; break;
             }
-            if (p > floor_sqrt)
+            if (p>32000 || (spx_int32_t)p*(spx_int32_t)p > n)
                 p = n;          /* no more factors, skip to end */
         }
         n /= p;
@@ -357,7 +355,6 @@
         *facbuf++ = n;
     } while (n > 1);
 }
-
 /*
  *
  * User-callable function to allocate all necessary storage space for the fft.
@@ -382,15 +379,22 @@
         int i;
         st->nfft=nfft;
         st->inverse = inverse_fft;
-
+#ifdef FIXED_POINT
         for (i=0;i<nfft;++i) {
-            const double pi=3.14159265358979323846264338327;
-            double phase = ( -2*pi /nfft ) * i;
-            if (st->inverse)
-                phase *= -1;
-            kf_cexp(st->twiddles+i, phase );
+            spx_word32_t phase = i;
+            if (!st->inverse)
+                phase = -phase;
+            kf_cexp2(st->twiddles+i, DIV32(SHL32(phase,17),nfft));
         }
-
+#else
+        for (i=0;i<nfft;++i) {
+           const double pi=3.14159265358979323846264338327;
+           double phase = ( -2*pi /nfft ) * i;
+           if (st->inverse)
+              phase *= -1;
+           kf_cexp(st->twiddles+i, phase );
+        }
+#endif
         kf_factor(nfft,st->factors);
     }
     return st;

Modified: trunk/speex/libspeex/kiss_fftr.c
===================================================================
--- trunk/speex/libspeex/kiss_fftr.c	2006-11-07 13:25:33 UTC (rev 12054)
+++ trunk/speex/libspeex/kiss_fftr.c	2006-11-07 15:02:52 UTC (rev 12055)
@@ -58,13 +58,22 @@
     st->super_twiddles = st->tmpbuf + nfft;
     kiss_fft_alloc(nfft, inverse_fft, st->substate, &subsize);
 
-    for (i = 0; i < nfft; ++i) {
-        double phase =
-            -3.14159265358979323846264338327 * ((double) i / nfft + .5);
-        if (inverse_fft)
-            phase *= -1;
-        kf_cexp (st->super_twiddles+i,phase);
+#ifdef FIXED_POINT
+    for (i=0;i<nfft;++i) {
+       spx_word32_t phase = i+(nfft>>1);
+       if (!inverse_fft)
+          phase = -phase;
+       kf_cexp2(st->super_twiddles+i, DIV32(SHL32(phase,16),nfft));
     }
+#else
+    for (i=0;i<nfft;++i) {
+       const double pi=3.14159265358979323846264338327;
+       double phase = pi*(((double)i) /nfft + .5);
+       if (!inverse_fft)
+          phase = -phase;
+       kf_cexp(st->super_twiddles+i, phase );
+    }
+#endif
     return st;
 }