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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 18:07:22 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 18:07:22 +0000
commitc04dcc2e7d834218ef2d4194331e383402495ae1 (patch)
tree7333e38d10d75386e60f336b80c2443c1166031d /xbmc/contrib/kissfft/kiss_fftr.c
parentInitial commit. (diff)
downloadkodi-c04dcc2e7d834218ef2d4194331e383402495ae1.tar.xz
kodi-c04dcc2e7d834218ef2d4194331e383402495ae1.zip
Adding upstream version 2:20.4+dfsg.upstream/2%20.4+dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'xbmc/contrib/kissfft/kiss_fftr.c')
-rw-r--r--xbmc/contrib/kissfft/kiss_fftr.c154
1 files changed, 154 insertions, 0 deletions
diff --git a/xbmc/contrib/kissfft/kiss_fftr.c b/xbmc/contrib/kissfft/kiss_fftr.c
new file mode 100644
index 0000000..e9d3fe9
--- /dev/null
+++ b/xbmc/contrib/kissfft/kiss_fftr.c
@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2003-2004, Mark Borgerding. All rights reserved.
+ * This file is part of KISS FFT - https://github.com/mborgerding/kissfft
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ * See COPYING file for more information.
+ */
+
+#include "kiss_fftr.h"
+
+#include "_kiss_fft_guts.h"
+
+struct kiss_fftr_state{
+ kiss_fft_cfg substate;
+ kiss_fft_cpx * tmpbuf;
+ kiss_fft_cpx * super_twiddles;
+#ifdef USE_SIMD
+ void * pad;
+#endif
+};
+
+kiss_fftr_cfg kiss_fftr_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem)
+{
+ int i;
+ kiss_fftr_cfg st = NULL;
+ size_t subsize, memneeded;
+
+ if (nfft & 1) {
+ fprintf(stderr,"Real FFT optimization must be even.\n");
+ return NULL;
+ }
+ nfft >>= 1;
+
+ kiss_fft_alloc (nfft, inverse_fft, NULL, &subsize);
+ memneeded = sizeof(struct kiss_fftr_state) + subsize + sizeof(kiss_fft_cpx) * ( nfft * 3 / 2);
+
+ if (lenmem == NULL) {
+ st = (kiss_fftr_cfg) KISS_FFT_MALLOC (memneeded);
+ } else {
+ if (*lenmem >= memneeded)
+ st = (kiss_fftr_cfg) mem;
+ *lenmem = memneeded;
+ }
+ if (!st)
+ return NULL;
+
+ st->substate = (kiss_fft_cfg) (st + 1); /*just beyond kiss_fftr_state struct */
+ st->tmpbuf = (kiss_fft_cpx *) (((char *) st->substate) + subsize);
+ st->super_twiddles = st->tmpbuf + nfft;
+ kiss_fft_alloc(nfft, inverse_fft, st->substate, &subsize);
+
+ for (i = 0; i < nfft/2; ++i) {
+ double phase =
+ -3.14159265358979323846264338327 * ((double) (i+1) / nfft + .5);
+ if (inverse_fft)
+ phase *= -1;
+ kf_cexp (st->super_twiddles+i,phase);
+ }
+ return st;
+}
+
+void kiss_fftr(kiss_fftr_cfg st,const kiss_fft_scalar *timedata,kiss_fft_cpx *freqdata)
+{
+ /* input buffer timedata is stored row-wise */
+ int k,ncfft;
+ kiss_fft_cpx fpnk,fpk,f1k,f2k,tw,tdc;
+
+ if ( st->substate->inverse) {
+ fprintf(stderr,"kiss fft usage error: improper alloc\n");
+ exit(1);
+ }
+
+ ncfft = st->substate->nfft;
+
+ /*perform the parallel fft of two real signals packed in real,imag*/
+ kiss_fft( st->substate , (const kiss_fft_cpx*)timedata, st->tmpbuf );
+ /* The real part of the DC element of the frequency spectrum in st->tmpbuf
+ * contains the sum of the even-numbered elements of the input time sequence
+ * The imag part is the sum of the odd-numbered elements
+ *
+ * The sum of tdc.r and tdc.i is the sum of the input time sequence.
+ * yielding DC of input time sequence
+ * The difference of tdc.r - tdc.i is the sum of the input (dot product) [1,-1,1,-1...
+ * yielding Nyquist bin of input time sequence
+ */
+
+ tdc.r = st->tmpbuf[0].r;
+ tdc.i = st->tmpbuf[0].i;
+ C_FIXDIV(tdc,2);
+ CHECK_OVERFLOW_OP(tdc.r ,+, tdc.i);
+ CHECK_OVERFLOW_OP(tdc.r ,-, tdc.i);
+ freqdata[0].r = tdc.r + tdc.i;
+ freqdata[ncfft].r = tdc.r - tdc.i;
+#ifdef USE_SIMD
+ freqdata[ncfft].i = freqdata[0].i = _mm_set1_ps(0);
+#else
+ freqdata[ncfft].i = freqdata[0].i = 0;
+#endif
+
+ for ( k=1;k <= ncfft/2 ; ++k ) {
+ fpk = st->tmpbuf[k];
+ fpnk.r = st->tmpbuf[ncfft-k].r;
+ fpnk.i = - st->tmpbuf[ncfft-k].i;
+ C_FIXDIV(fpk,2);
+ C_FIXDIV(fpnk,2);
+
+ C_ADD( f1k, fpk , fpnk );
+ C_SUB( f2k, fpk , fpnk );
+ C_MUL( tw , f2k , st->super_twiddles[k-1]);
+
+ freqdata[k].r = HALF_OF(f1k.r + tw.r);
+ freqdata[k].i = HALF_OF(f1k.i + tw.i);
+ freqdata[ncfft-k].r = HALF_OF(f1k.r - tw.r);
+ freqdata[ncfft-k].i = HALF_OF(tw.i - f1k.i);
+ }
+}
+
+void kiss_fftri(kiss_fftr_cfg st,const kiss_fft_cpx *freqdata,kiss_fft_scalar *timedata)
+{
+ /* input buffer timedata is stored row-wise */
+ int k, ncfft;
+
+ if (st->substate->inverse == 0) {
+ fprintf (stderr, "kiss fft usage error: improper alloc\n");
+ exit (1);
+ }
+
+ ncfft = st->substate->nfft;
+
+ st->tmpbuf[0].r = freqdata[0].r + freqdata[ncfft].r;
+ st->tmpbuf[0].i = freqdata[0].r - freqdata[ncfft].r;
+ C_FIXDIV(st->tmpbuf[0],2);
+
+ for (k = 1; k <= ncfft / 2; ++k) {
+ kiss_fft_cpx fk, fnkc, fek, fok, tmp;
+ fk = freqdata[k];
+ fnkc.r = freqdata[ncfft - k].r;
+ fnkc.i = -freqdata[ncfft - k].i;
+ C_FIXDIV( fk , 2 );
+ C_FIXDIV( fnkc , 2 );
+
+ C_ADD (fek, fk, fnkc);
+ C_SUB (tmp, fk, fnkc);
+ C_MUL (fok, tmp, st->super_twiddles[k-1]);
+ C_ADD (st->tmpbuf[k], fek, fok);
+ C_SUB (st->tmpbuf[ncfft - k], fek, fok);
+#ifdef USE_SIMD
+ st->tmpbuf[ncfft - k].i *= _mm_set1_ps(-1.0);
+#else
+ st->tmpbuf[ncfft - k].i *= -1;
+#endif
+ }
+ kiss_fft (st->substate, st->tmpbuf, (kiss_fft_cpx *) timedata);
+}