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fast conv filtering small edits

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2d files no longer needed with kiss_fftnd
This commit is contained in:
Mark Borgerding
2004-01-24 01:34:01 +00:00
parent ca97282da6
commit 25e377eaa8
5 changed files with 30 additions and 122 deletions
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61
tools/kiss_fastfir.c
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@ -30,7 +30,7 @@ typedef kiss_fft_cpx kffsamp_t;
static int verbose=0;
void * kiss_fastfir_alloc(const kffsamp_t * imp_resp,size_t n_imp_resp,
int nfft,void * mem,size_t*lenmem);
size_t * nfft,void * mem,size_t*lenmem);
typedef struct {
int nfft;
@ -47,7 +47,7 @@ static const kiss_fft_cpx CZERO={0,0};
void * kiss_fastfir_alloc(
const kffsamp_t * imp_resp,size_t n_imp_resp,
int nfft, /* if <= 0, an appropriate size will be chosen */
size_t *pnfft, /* if <= 0, an appropriate size will be chosen */
void * mem,size_t*lenmem)
{
kiss_fastfir_state *st = NULL;
@ -55,8 +55,11 @@ void * kiss_fastfir_alloc(
size_t memneeded = sizeof(kiss_fastfir_state);
char * ptr;
size_t i;
int nfft=0;
float scale;
int n_freq_bins;
if (pnfft)
nfft=*pnfft;
if (nfft<=0) {
/* determine fft size as next power of two at least 2x
@ -79,10 +82,8 @@ void * kiss_fastfir_alloc(
/*ifftcfg*/
FFT_ALLOC (nfft, 1, NULL, &len_ifftcfg);
memneeded += len_ifftcfg;
/* tmpbuf */
memneeded += sizeof(kffsamp_t) * nfft;
/* fir_freq_resp */
memneeded += sizeof(kiss_fft_cpx) * n_freq_bins;
/* freqbuf */
@ -123,7 +124,7 @@ void * kiss_fastfir_alloc(
memset(st->tmpbuf,0,sizeof(kffsamp_t)*nfft);
/*zero pad in the middle to left-rotate the impulse response
* This puts the scrap samples at the end of the inverse fft'd buffer */
This puts the scrap samples at the end of the inverse fft'd buffer */
st->tmpbuf[0] = imp_resp[ n_imp_resp - 1 ];
for (i=0;i<n_imp_resp - 1; ++i) {
st->tmpbuf[ nfft - n_imp_resp + 1 + i ] = imp_resp[ i ];
@ -138,6 +139,8 @@ void * kiss_fastfir_alloc(
st->fir_freq_resp[i].r *= scale;
st->fir_freq_resp[i].i *= scale;
}
if (pnfft)
*pnfft = nfft;
return st;
}
@ -145,7 +148,6 @@ static void fastconv1buf(const kiss_fastfir_state *st,const kffsamp_t * in,kffsa
{
int i;
FFTFWD( st->fftcfg, in , st->freqbuf );
/* multiply the frequency response of the input signal by*/
/* that of the fir filter*/
for ( i=0; i<st->n_freq_bins; ++i ) {
@ -182,8 +184,6 @@ size_t kff_nocopy(
#ifdef FAST_FILT_UTIL
#define BUFLEN 1024
void do_filter(
FILE * fin,
FILE * fout,
@ -191,53 +191,48 @@ void do_filter(
size_t n_imp_resp,
size_t nfft)
{
void * cfg = kiss_fastfir_alloc(imp_resp,n_imp_resp,nfft,0,0);
size_t max_inbuf=5*nfft;
size_t max_outbuf=5*nfft;
kffsamp_t *inbuf;
kffsamp_t *outbuf;
void * cfg = kiss_fastfir_alloc(imp_resp,n_imp_resp,&nfft,0,0);
size_t max_buf=5*nfft;
kffsamp_t *inbuf = (kffsamp_t*)malloc(max_buf*sizeof(kffsamp_t));
kffsamp_t *outbuf = (kffsamp_t*)malloc(max_buf*sizeof(kffsamp_t));
size_t ninbuf,noutbuf;
size_t idx_inbuf=0;
int done=0;
inbuf = (kffsamp_t*)malloc(max_inbuf*sizeof(kffsamp_t));
outbuf = (kffsamp_t*)malloc(max_outbuf*sizeof(kffsamp_t));
int zpad=0;
do{
int zpad=0;
ninbuf = fread(&inbuf[idx_inbuf],sizeof(inbuf[0]),max_inbuf-idx_inbuf,fin );
ninbuf = fread(&inbuf[idx_inbuf],sizeof(inbuf[0]),max_buf-idx_inbuf,fin );
if (ninbuf==0) {
/* zero pad the input to the fft size */
done=1;
zpad = nfft - idx_inbuf;
memset(&inbuf[idx_inbuf],0,sizeof(inbuf[0])*zpad);
if (verbose) fprintf(stderr,"zero padding %d samples\n",zpad);
ninbuf = nfft;
/* We don't strictly need to do the zero padding,since the output samples
* will get thrown away anyway. But the zeros should help keep the fft magnitudes in
* check and thus decrease errors. */
memset(&inbuf[idx_inbuf],0,sizeof(inbuf[0])*zpad);
ninbuf = nfft;/* force an fft */
}else{
ninbuf += idx_inbuf;
}
/*perform the fast convolution filtering*/
noutbuf = kff_nocopy( cfg, inbuf, outbuf, ninbuf );
if (verbose) fprintf(stderr,"kff_nocopy(,,,%d) -> %d\n",ninbuf,noutbuf);
/* move the unconsumed samples to the front */
idx_inbuf = ninbuf-noutbuf;
memmove( inbuf , &inbuf[noutbuf] , sizeof(inbuf[0])*(ninbuf-noutbuf) );
/* move the unconsumed input samples to the front */
idx_inbuf = ninbuf - noutbuf;
memmove( inbuf , &inbuf[noutbuf] , sizeof(inbuf[0])*(ninbuf-noutbuf) );
if (verbose) fprintf(stderr,"moved %d samples to front of buffer\n",idx_inbuf);
/*whatever padding was done to get the size up to nfft, must now be ignored*/
noutbuf -= zpad;
if ( fwrite( outbuf,
sizeof(outbuf[0]),
noutbuf,
fout)
!= noutbuf )
{
if ( fwrite( outbuf, sizeof(outbuf[0]), noutbuf, fout) != noutbuf ) {
fprintf(stderr,"short write %d \n",noutbuf);
fprintf(stderr,"zpad= %d \n",zpad);
exit(1);
}
}while ( ! done );
}while ( ! zpad );
fclose(fout);
free(cfg);
free(inbuf);