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Float FFT now does the same scaling as the fixed-point FFT

--- a/libcelt/_kiss_fft_guts.h

+++ b/libcelt/_kiss_fft_guts.h

@@ -29,6 +29,9 @@

 struct kiss_fft_state{

     int nfft;

+#ifndef FIXED_POINT

+    kiss_fft_scalar scale;

+#endif

     int factors[2*MAXFACTORS];

     int *bitrev;

     kiss_twiddle_cpx twiddles[1];

--- a/libcelt/kiss_fft.c

+++ b/libcelt/kiss_fft.c

@@ -617,6 +617,9 @@

     if (st) {

         int i;

         st->nfft=nfft;

+#ifndef FIXED_POINT

+        st->scale = 1./nfft;

+#endif

 #if defined(FIXED_POINT) && (!defined(DOUBLE_PRECISION) || defined(MIXED_PRECISION))

         for (i=0;i<nfft;++i) {

             celt_word32_t phase = -i;

@@ -650,7 +653,13 @@

        /* Bit-reverse the input */

        int i;

        for (i=0;i<st->nfft;i++)

+       {

           fout[i] = fin[st->bitrev[i]];

+#ifndef FIXED_POINT

+          fout[i].r *= st->scale;

+          fout[i].i *= st->scale;

+#endif

+       }

        kf_work( fout, fin, 1,in_stride, st->factors,st, 1, in_stride, 1);

     }

 }

--- a/libcelt/kiss_fftr.c

+++ b/libcelt/kiss_fftr.c

@@ -62,6 +62,9 @@

     st->tmpbuf = (kiss_fft_cpx *) (((char *) st->substate) + subsize);

     st->super_twiddles = (kiss_twiddle_cpx*)(st->tmpbuf + nfft);

     kiss_fft_alloc(nfft, st->substate, &subsize);

+#ifndef FIXED_POINT

+    st->substate->scale *= .5;

+#endif

 #if defined (FIXED_POINT) && !defined(DOUBLE_PRECISION)

     for (i=0;i<nfft;++i) {

--- a/libcelt/mdct.c

+++ b/libcelt/mdct.c

@@ -114,8 +114,8 @@

    /* Post-rotate and apply the scaling if the FFT doesn't to it itself */

    for(i=0;i<N4;i++)

    {

-      out[2*i]      = l->scale * (-f[2*i+1]*l->trig[i+N4] + f[2*i]  *l->trig[i]);

-      out[N2-1-2*i] = l->scale * (-f[2*i]  *l->trig[i+N4] - f[2*i+1]*l->trig[i]);

+      out[2*i]      = -f[2*i+1]*l->trig[i+N4] + f[2*i]  *l->trig[i];

+      out[N2-1-2*i] = -f[2*i]  *l->trig[i+N4] - f[2*i+1]*l->trig[i];

    }

 }

--- a/tests/dft-test.c

+++ b/tests/dft-test.c

@@ -25,13 +25,11 @@

             if (isinverse)

                 im = -im;

-#ifdef FIXED_POINT

             if (!isinverse)

             {

                re /= nfft;

                im /= nfft;

             }

-#endif            

             ansr += in[k].r * re - in[k].i * im;

             ansi += in[k].r * im + in[k].i * re;

--- a/tests/real-fft-test.c

+++ b/tests/real-fft-test.c

@@ -4,21 +4,11 @@

 #include "kiss_fftr.h"

 #include "_kiss_fft_guts.h"

-#include <sys/times.h>

-#include <time.h>

-#include <unistd.h>

 #include <stdio.h>

 #include <string.h>

 int ret=0;

-static double cputime(void)

-{

-    struct tms t;

-    times(&t);

-    return (double)(t.tms_utime + t.tms_stime)/  sysconf(_SC_CLK_TCK) ;

-}

-

 static

 kiss_fft_scalar rand_scalar(void) 

 {

@@ -80,7 +70,6 @@

 int main(void)

 {

-    double ts,tfft,trfft;

     int i;

     kiss_fft_cpx cin[NFFT];

     kiss_fft_cpx cout[NFFT];

@@ -109,20 +98,6 @@

     printf( "nfft=%d, inverse=%d, snr=%g\n",

             NFFT,0, snr_compare(cout,sout,(NFFT/2)) );

-    ts = cputime();

-    for (i=0;i<NUMFFTS;++i) {

-        kiss_fft(kiss_fft_state,cin,cout);

-    }

-    tfft = cputime() - ts;

-    

-    ts = cputime();

-    for (i=0;i<NUMFFTS;++i) {

-        kiss_fftr( kiss_fftr_state, rin, sout );

-        /* kiss_fftri(kiss_fftr_state,cout,rin); */

-    }

-    trfft = cputime() - ts;

-

-    printf("%d complex ffts took %gs, real took %gs\n",NUMFFTS,tfft,trfft);

     memset(cin,0,sizeof(cin));

 #if 1