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slightly closer, still overflows in some cases

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This commit is contained in:
Mark Borgerding 2004-01-02 22:28:03 +00:00
parent e749a114cb
commit 8ffc08b07b
1 changed files with 42 additions and 16 deletions
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58
tools/kiss_fastfir.c
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@ -142,6 +142,12 @@ void * kiss_fastfir_alloc(const kffsamp_t * imp_resp,size_t n_imp_resp,
st->fir_freq_resp[i].i *= scale; st->fir_freq_resp[i].i *= scale;
} }
fprintf(stderr,
"nfft==%d\n"
"n_scrap==%d\n"
"output on %d+k*%d\n"
"\n" ,st->nfft, st->n_scrap ,st->nfft,st->nfft-n_imp_resp+1 );
return st; return st;
} }
@ -151,6 +157,9 @@ size_t write_output(kiss_fastfir_state *st,
{ {
size_t nout = *pnout; size_t nout = *pnout;
size_t n2flush = st->nfft - st->bufout_idx; size_t n2flush = st->nfft - st->bufout_idx;
if (nout==0)
return 0;
if (zpadded) if (zpadded)
n2flush -= zpadded; n2flush -= zpadded;
if ( nout < n2flush ) if ( nout < n2flush )
@ -166,8 +175,11 @@ static void do_fastconv(kiss_fastfir_state *st)
int i; int i;
if ( st->bufout_idx < st->nfft ) { if ( st->bufout_idx < st->nfft ) {
fprintf(stderr,"kiss_fastfir warning: " fprintf(stderr,"kiss_fastfir warning: "
" output buffer size must be >= input buffer size," " output buffer size must be > input buffer size,"
" %d samples lost\n",st->nfft - st->bufout_idx ); " %d samples lost\n",st->nfft - st->bufout_idx );
fprintf(stderr,"bufin_idx = %d\n",st->bufin_idx);
fprintf(stderr,"bufout_idx = %d\n",st->bufout_idx);
exit(1);
} }
/*FFT st->bufin to st->tmpbuf*/ /*FFT st->bufin to st->tmpbuf*/
FFTFWD(st->fftcfg,st->bufin,st->tmpbuf); FFTFWD(st->fftcfg,st->bufin,st->tmpbuf);
@ -203,24 +215,30 @@ size_t kiss_fastfir(const void * cfg,
out += write_output(st,out,&nout_avail,0); out += write_output(st,out,&nout_avail,0);
if ( nin <= 0 ) { if ( nin <= 0 && st->bufin_idx > st->n_scrap ) {
size_t zero_pad = st->nfft - st->bufin_idx; size_t zero_pad = st->nfft - st->bufin_idx;
memset( st->bufin + st->bufin_idx, 0, zero_pad*sizeof(kiss_fft_cpx) ); memset( st->bufin + st->bufin_idx, 0, zero_pad*sizeof(kffsamp_t) );
st->bufin_idx = st->nfft; st->bufin_idx = st->nfft;
do_fastconv(st); do_fastconv(st);
if (zero_pad) {
int i;
for ( i=st->nfft-1; i>=zero_pad; --i )
st->bufout[i] = st->bufout[i-zero_pad];
st->bufout_idx += zero_pad;
}
fprintf(stderr,"padded with %d zeros\n",zero_pad); fprintf(stderr,"padded with %d zeros\n",zero_pad);
return write_output(st,out,&nout_avail,zero_pad); out += write_output(st,out,&nout_avail,0);
} }else {
while (nin--) {
/* copy the input sample to bufin*/
st->bufin[st->bufin_idx++] = *in++;
while (nin--) { /* when the input buffer is full, perform fast convolution*/
/* copy the input sample to bufin*/ if ( st->bufin_idx == st->nfft ) {
st->bufin[st->bufin_idx++] = *in++; do_fastconv(st);
/* write the output buffer*/
/* when the input buffer is full, perform fast convolution*/ out += write_output(st,out,&nout_avail,0);
if ( st->bufin_idx == st->nfft ) { }
do_fastconv(st);
/* write the output buffer*/
out += write_output(st,out,&nout_avail,0);
} }
} }
return nout_orig - nout_avail; return nout_orig - nout_avail;
@ -238,17 +256,25 @@ void do_filter(
size_t nfft) size_t nfft)
{ {
void * cfg = kiss_fastfir_alloc(imp_resp,n_imp_resp,nfft,0,0); void * cfg = kiss_fastfir_alloc(imp_resp,n_imp_resp,nfft,0,0);
kffsamp_t inbuf[BUFLEN],outbuf[BUFLEN]; kffsamp_t inbuf[BUFLEN],outbuf[BUFLEN+1];
size_t ninbuf,noutbuf; size_t ninbuf,noutbuf;
do{ do{
ninbuf = fread(inbuf,sizeof(inbuf[0]),BUFLEN,fin ); ninbuf = fread(inbuf,sizeof(inbuf[0]),BUFLEN,fin );
/* when ninbuf <= 0, that signals a flush*/ /* when ninbuf <= 0, that signals a flush*/
noutbuf = kiss_fastfir(cfg,inbuf,ninbuf,outbuf,BUFLEN); noutbuf = kiss_fastfir(cfg,inbuf,ninbuf,outbuf,BUFLEN+1);
if ( fwrite(outbuf,sizeof(outbuf[0]),noutbuf,fout) != noutbuf ) { if ( fwrite(outbuf,sizeof(outbuf[0]),noutbuf,fout) != noutbuf ) {
fprintf(stderr,"short write\n"); fprintf(stderr,"short write\n");
exit(1); exit(1);
} }
}while(ninbuf>0); }while(ninbuf>0);
do{
noutbuf = kiss_fastfir(cfg,NULL,0,outbuf,BUFLEN);
if ( fwrite(outbuf,sizeof(outbuf[0]),noutbuf,fout) != noutbuf ) {
fprintf(stderr,"short write\n");
exit(1);
}
}while(noutbuf);
fclose(fout); fclose(fout);
free(cfg); free(cfg);
} }