ref: a4863786d27a554fdd1929d6b1ca4516c541b05f
author: Sigrid Solveig Haflínudóttir <ftrvxmtrx@gmail.com>
date: Wed Nov 25 10:50:08 EST 2020
trans rights
--- /dev/null
+++ b/LICENSE
@@ -1,0 +1,18 @@
+Copyright © 2020 Sigrid Solveig Haflínudóttir
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
--- /dev/null
+++ b/LICENSE.kiss-fft
@@ -1,0 +1,30 @@
+BSD 3-Clause License
+
+Copyright (c) 2003-2010 Mark Borgerding
+Copyright (c) 2017, Bernd Porr
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+ list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+ contributors may be used to endorse or promote products derived from
+ this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
--- /dev/null
+++ b/README.md
@@ -1,0 +1,18 @@
+# games/pitch
+
+
+
+9front says TRANS RIGHTS!
+
+A simple voice pitch analyzer.
+
+The only option available for now is the input, which is `/dev/audio`
+by default. It's recommended to increase `recgain` through
+`/dev/volume` in order to achieve best results. You might want a
+better mic (the built-in ones suck).
+
+## Attribution
+
+The program is using kiss-fft, which is a fork (done by Bernd Porr),
+stripped down and further debugged version of the original kiss-fft
+library by Mark Borgerding, see `LICENSE.kiss-fft` file.
--- /dev/null
+++ b/_kiss_fft_guts.h
@@ -1,0 +1,159 @@
+/*
+Copyright (c) 2003-2010, Mark Borgerding
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+ * Neither the author nor the names of any contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/* kiss_fft.h
+ defines kiss_fft_scalar as either short or a float type
+ and defines
+ typedef struct { kiss_fft_scalar r; kiss_fft_scalar i; }kiss_fft_cpx; */+#include "kiss_fft.h"
+
+#define MAXFACTORS 32
+/* e.g. an fft of length 128 has 4 factors
+ as far as kissfft is concerned
+ 4*4*4*2
+ */
+
+struct kiss_fft_state{+ int nfft;
+ int inverse;
+ int factors[2*MAXFACTORS];
+ kiss_fft_cpx twiddles[1];
+};
+
+/*
+ Explanation of macros dealing with complex math:
+
+ C_MUL(m,a,b) : m = a*b
+ C_FIXDIV( c , div ) : if a fixed point impl., c /= div. noop otherwise
+ C_SUB( res, a,b) : res = a - b
+ C_SUBFROM( res , a) : res -= a
+ C_ADDTO( res , a) : res += a
+ * */
+#ifdef FIXED_POINT
+#if (FIXED_POINT==32)
+# define FRACBITS 31
+# define SAMPPROD int64_t
+#define SAMP_MAX 2147483647
+#else
+# define FRACBITS 15
+# define SAMPPROD s32int
+#define SAMP_MAX 32767
+#endif
+
+#define SAMP_MIN -SAMP_MAX
+
+#if defined(CHECK_OVERFLOW)
+# define CHECK_OVERFLOW_OP(a,op,b) \
+ if ( (SAMPPROD)(a) op (SAMPPROD)(b) > SAMP_MAX || (SAMPPROD)(a) op (SAMPPROD)(b) < SAMP_MIN ) { \+ fprintf(stderr,"WARNING:overflow @ " __FILE__ "(%d): (%d " #op" %d) = %ld\n",__LINE__,(a),(b),(SAMPPROD)(a) op (SAMPPROD)(b) ); }
+#endif
+
+
+# define smul(a,b) ( (SAMPPROD)(a)*(b) )
+# define sround( x ) (kiss_fft_scalar)( ( (x) + (1<<(FRACBITS-1)) ) >> FRACBITS )
+
+# define S_MUL(a,b) sround( smul(a,b) )
+
+# define C_MUL(m,a,b) \
+ do{ (m).r = sround( smul((a).r,(b).r) - smul((a).i,(b).i) ); \+ (m).i = sround( smul((a).r,(b).i) + smul((a).i,(b).r) ); }while(0)
+
+# define DIVSCALAR(x,k) \
+ (x) = sround( smul( x, SAMP_MAX/k ) )
+
+# define C_FIXDIV(c,div) \
+ do { DIVSCALAR( (c).r , div); \+ DIVSCALAR( (c).i , div); }while (0)
+
+# define C_MULBYSCALAR( c, s ) \
+ do{ (c).r = sround( smul( (c).r , s ) ) ;\+ (c).i = sround( smul( (c).i , s ) ) ; }while(0)
+
+#else /* not FIXED_POINT*/
+
+# define S_MUL(a,b) ( (a)*(b) )
+#define C_MUL(m,a,b) \
+ do{ (m).r = (a).r*(b).r - (a).i*(b).i;\+ (m).i = (a).r*(b).i + (a).i*(b).r; }while(0)
+# define C_FIXDIV(c,div) /* NOOP */
+# define C_MULBYSCALAR( c, s ) \
+ do{ (c).r *= (s);\+ (c).i *= (s); }while(0)
+#endif
+
+#ifndef CHECK_OVERFLOW_OP
+# define CHECK_OVERFLOW_OP(a,op,b) /* noop */
+#endif
+
+#define C_ADD( res, a,b)\
+ do { \+ CHECK_OVERFLOW_OP((a).r,+,(b).r)\
+ CHECK_OVERFLOW_OP((a).i,+,(b).i)\
+ (res).r=(a).r+(b).r; (res).i=(a).i+(b).i; \
+ }while(0)
+#define C_SUB( res, a,b)\
+ do { \+ CHECK_OVERFLOW_OP((a).r,-,(b).r)\
+ CHECK_OVERFLOW_OP((a).i,-,(b).i)\
+ (res).r=(a).r-(b).r; (res).i=(a).i-(b).i; \
+ }while(0)
+#define C_ADDTO( res , a)\
+ do { \+ CHECK_OVERFLOW_OP((res).r,+,(a).r)\
+ CHECK_OVERFLOW_OP((res).i,+,(a).i)\
+ (res).r += (a).r; (res).i += (a).i;\
+ }while(0)
+
+#define C_SUBFROM( res , a)\
+ do {\+ CHECK_OVERFLOW_OP((res).r,-,(a).r)\
+ CHECK_OVERFLOW_OP((res).i,-,(a).i)\
+ (res).r -= (a).r; (res).i -= (a).i; \
+ }while(0)
+
+
+#ifdef FIXED_POINT
+# define KISS_FFT_COS(phase) floor(.5+SAMP_MAX * cos (phase))
+# define KISS_FFT_SIN(phase) floor(.5+SAMP_MAX * sin (phase))
+# define HALF_OF(x) ((x)>>1)
+#else
+# define KISS_FFT_COS(phase) (kiss_fft_scalar) cos(phase)
+# define KISS_FFT_SIN(phase) (kiss_fft_scalar) sin(phase)
+# define HALF_OF(x) ((x)*.5)
+#endif
+
+#define kf_cexp(x,phase) \
+ do{ \+ (x)->r = KISS_FFT_COS(phase);\
+ (x)->i = KISS_FFT_SIN(phase);\
+ }while(0)
+
+
+/* a debugging function */
+#define pcpx(c)\
+ fprintf(stderr,"%g + %gi\n",(double)((c)->r),(double)((c)->i) )
+
+
+#ifdef KISS_FFT_USE_ALLOCA
+// define this to allow use of alloca instead of malloc for temporary buffers
+// Temporary buffers are used in two case:
+// 1. FFT sizes that have "bad" factors. i.e. not 2,3 and 5
+// 2. "in-place" FFTs. Notice the quotes, since kissfft does not really do an in-place transform.
+#include <alloca.h>
+#define KISS_FFT_TMP_ALLOC(nbytes) alloca(nbytes)
+#define KISS_FFT_TMP_FREE(ptr)
+#else
+#define KISS_FFT_TMP_ALLOC(nbytes) KISS_FFT_MALLOC(nbytes)
+#define KISS_FFT_TMP_FREE(ptr) KISS_FFT_FREE(ptr)
+#endif
--- /dev/null
+++ b/kiss_fft.c
@@ -1,0 +1,400 @@
+/*
+Copyright (c) 2003-2010, Mark Borgerding
+Copyright (c) 2017, Bernd Porr
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+ * Neither the author nor the names of any contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <u.h>
+#include <libc.h>
+
+#include "_kiss_fft_guts.h"
+
+/* The guts header contains all the multiplication and addition macros that are defined for
+ fixed or floating point complex numbers. It also delares the kf_ internal functions.
+ */
+
+static void kf_bfly2(
+ kiss_fft_cpx *Fout,
+ const usize fstride,
+ const kiss_fft_cfg *st,
+ int m
+) {+ kiss_fft_cpx *Fout2;
+ kiss_fft_cpx *tw1 = st->twiddles;
+ kiss_fft_cpx t;
+ Fout2 = Fout + m;
+ do {+ C_FIXDIV(*Fout, 2); C_FIXDIV(*Fout2, 2);
+
+ C_MUL (t, *Fout2, *tw1);
+ tw1 += fstride;
+ C_SUB(*Fout2, *Fout, t);
+ C_ADDTO(*Fout, t);
+ ++Fout2;
+ ++Fout;
+ } while (--m);
+}
+
+static void kf_bfly4(
+ kiss_fft_cpx *Fout,
+ const usize fstride,
+ const kiss_fft_cfg *st,
+ const usize m
+) {+ kiss_fft_cpx *tw1, *tw2, *tw3;
+ kiss_fft_cpx scratch[6];
+ usize k = m;
+ const usize m2 = 2 * m;
+ const usize m3 = 3 * m;
+
+
+ tw3 = tw2 = tw1 = st->twiddles;
+
+ do {+ C_FIXDIV(*Fout, 4); C_FIXDIV(Fout[m], 4); C_FIXDIV(Fout[m2], 4); C_FIXDIV(Fout[m3], 4);
+
+ C_MUL(scratch[0], Fout[m], *tw1);
+ C_MUL(scratch[1], Fout[m2], *tw2);
+ C_MUL(scratch[2], Fout[m3], *tw3);
+
+ C_SUB(scratch[5], *Fout, scratch[1]);
+ C_ADDTO(*Fout, scratch[1]);
+ C_ADD(scratch[3], scratch[0], scratch[2]);
+ C_SUB(scratch[4], scratch[0], scratch[2]);
+ C_SUB(Fout[m2], *Fout, scratch[3]);
+ tw1 += fstride;
+ tw2 += fstride * 2;
+ tw3 += fstride * 3;
+ C_ADDTO(*Fout, scratch[3]);
+
+ if (st->inverse) {+ Fout[m].r = scratch[5].r - scratch[4].i;
+ Fout[m].i = scratch[5].i + scratch[4].r;
+ Fout[m3].r = scratch[5].r + scratch[4].i;
+ Fout[m3].i = scratch[5].i - scratch[4].r;
+ } else {+ Fout[m].r = scratch[5].r + scratch[4].i;
+ Fout[m].i = scratch[5].i - scratch[4].r;
+ Fout[m3].r = scratch[5].r - scratch[4].i;
+ Fout[m3].i = scratch[5].i + scratch[4].r;
+ }
+ ++Fout;
+ } while (--k);
+}
+
+static void kf_bfly3(
+ kiss_fft_cpx *Fout,
+ const usize fstride,
+ const kiss_fft_cfg *st,
+ usize m
+) {+ usize k = m;
+ const usize m2 = 2 * m;
+ kiss_fft_cpx *tw1, *tw2;
+ kiss_fft_cpx scratch[5];
+ kiss_fft_cpx epi3;
+ epi3 = st->twiddles[fstride * m];
+
+ tw1 = tw2 = st->twiddles;
+
+ do {+ C_FIXDIV(*Fout, 3); C_FIXDIV(Fout[m], 3); C_FIXDIV(Fout[m2], 3);
+
+ C_MUL(scratch[1], Fout[m], *tw1);
+ C_MUL(scratch[2], Fout[m2], *tw2);
+
+ C_ADD(scratch[3], scratch[1], scratch[2]);
+ C_SUB(scratch[0], scratch[1], scratch[2]);
+ tw1 += fstride;
+ tw2 += fstride * 2;
+
+ Fout[m].r = Fout->r - HALF_OF(scratch[3].r);
+ Fout[m].i = Fout->i - HALF_OF(scratch[3].i);
+
+ C_MULBYSCALAR(scratch[0], epi3.i);
+
+ C_ADDTO(*Fout, scratch[3]);
+
+ Fout[m2].r = Fout[m].r + scratch[0].i;
+ Fout[m2].i = Fout[m].i - scratch[0].r;
+
+ Fout[m].r -= scratch[0].i;
+ Fout[m].i += scratch[0].r;
+
+ ++Fout;
+ } while (--k);
+}
+
+static void kf_bfly5(
+ kiss_fft_cpx *Fout,
+ const usize fstride,
+ const kiss_fft_cfg *st,
+ int m
+) {+ kiss_fft_cpx *Fout0, *Fout1, *Fout2, *Fout3, *Fout4;
+ int u;
+ kiss_fft_cpx scratch[13];
+ kiss_fft_cpx *twiddles = st->twiddles;
+ kiss_fft_cpx *tw;
+ kiss_fft_cpx ya, yb;
+ ya = twiddles[fstride * m];
+ yb = twiddles[fstride * 2 * m];
+
+ Fout0 = Fout;
+ Fout1 = Fout0 + m;
+ Fout2 = Fout0 + 2 * m;
+ Fout3 = Fout0 + 3 * m;
+ Fout4 = Fout0 + 4 * m;
+
+ tw = st->twiddles;
+ for (u = 0; u < m; ++u) {+ C_FIXDIV(*Fout0, 5); C_FIXDIV(*Fout1, 5); C_FIXDIV(*Fout2, 5); C_FIXDIV(*Fout3,
+ 5); C_FIXDIV(*Fout4,
+ 5);
+ scratch[0] = *Fout0;
+
+ C_MUL(scratch[1], *Fout1, tw[u * fstride]);
+ C_MUL(scratch[2], *Fout2, tw[2 * u * fstride]);
+ C_MUL(scratch[3], *Fout3, tw[3 * u * fstride]);
+ C_MUL(scratch[4], *Fout4, tw[4 * u * fstride]);
+
+ C_ADD(scratch[7], scratch[1], scratch[4]);
+ C_SUB(scratch[10], scratch[1], scratch[4]);
+ C_ADD(scratch[8], scratch[2], scratch[3]);
+ C_SUB(scratch[9], scratch[2], scratch[3]);
+
+ Fout0->r += scratch[7].r + scratch[8].r;
+ Fout0->i += scratch[7].i + scratch[8].i;
+
+ scratch[5].r = scratch[0].r + S_MUL(scratch[7].r, ya.r) + S_MUL(scratch[8].r, yb.r);
+ scratch[5].i = scratch[0].i + S_MUL(scratch[7].i, ya.r) + S_MUL(scratch[8].i, yb.r);
+
+ scratch[6].r = S_MUL(scratch[10].i, ya.i) + S_MUL(scratch[9].i, yb.i);
+ scratch[6].i = -S_MUL(scratch[10].r, ya.i) - S_MUL(scratch[9].r, yb.i);
+
+ C_SUB(*Fout1, scratch[5], scratch[6]);
+ C_ADD(*Fout4, scratch[5], scratch[6]);
+
+ scratch[11].r = scratch[0].r + S_MUL(scratch[7].r, yb.r) + S_MUL(scratch[8].r, ya.r);
+ scratch[11].i = scratch[0].i + S_MUL(scratch[7].i, yb.r) + S_MUL(scratch[8].i, ya.r);
+ scratch[12].r = -S_MUL(scratch[10].i, yb.i) + S_MUL(scratch[9].i, ya.i);
+ scratch[12].i = S_MUL(scratch[10].r, yb.i) - S_MUL(scratch[9].r, ya.i);
+
+ C_ADD(*Fout2, scratch[11], scratch[12]);
+ C_SUB(*Fout3, scratch[11], scratch[12]);
+
+ ++Fout0;
+ ++Fout1;
+ ++Fout2;
+ ++Fout3;
+ ++Fout4;
+ }
+}
+
+/* perform the butterfly for one stage of a mixed radix FFT */
+static void kf_bfly_generic(
+ kiss_fft_cpx *Fout,
+ const usize fstride,
+ const kiss_fft_cfg *st,
+ int m,
+ int p
+) {+ int u, k, q1, q;
+ kiss_fft_cpx *twiddles = st->twiddles;
+ kiss_fft_cpx t;
+ int Norig = st->nfft;
+
+ kiss_fft_cpx *scratch = (kiss_fft_cpx *) KISS_FFT_TMP_ALLOC(sizeof(kiss_fft_cpx) * p);
+
+ for (u = 0; u < m; ++u) {+ k = u;
+ for (q1 = 0; q1 < p; ++q1) {+ scratch[q1] = Fout[k];
+ C_FIXDIV(scratch[q1], p);
+ k += m;
+ }
+
+ k = u;
+ for (q1 = 0; q1 < p; ++q1) {+ int twidx = 0;
+ Fout[k] = scratch[0];
+ for (q = 1; q < p; ++q) {+ twidx += fstride * k;
+ if (twidx >= Norig) twidx -= Norig;
+ C_MUL(t, scratch[q], twiddles[twidx]);
+ C_ADDTO(Fout[k], t);
+ }
+ k += m;
+ }
+ }
+ KISS_FFT_TMP_FREE(scratch);
+}
+
+static
+void kf_work(
+ kiss_fft_cpx *Fout,
+ const kiss_fft_cpx *f,
+ const usize fstride,
+ int in_stride,
+ int *factors,
+ const kiss_fft_cfg *st
+) {+ kiss_fft_cpx *Fout_beg = Fout;
+ const int p = *factors++; /* the radix */
+ const int m = *factors++; /* stage's fft length/p */
+ const kiss_fft_cpx *Fout_end = Fout + p * m;
+
+ if (m == 1) {+ do {+ *Fout = *f;
+ f += fstride * in_stride;
+ } while (++Fout != Fout_end);
+ } else {+ do {+ // recursive call:
+ // DFT of size m*p performed by doing
+ // p instances of smaller DFTs of size m,
+ // each one takes a decimated version of the input
+ kf_work(Fout, f, fstride * p, in_stride, factors, st);
+ f += fstride * in_stride;
+ } while ((Fout += m) != Fout_end);
+ }
+
+ Fout = Fout_beg;
+
+ // recombine the p smaller DFTs
+ switch (p) {+ case 2:
+ kf_bfly2(Fout, fstride, st, m);
+ break;
+ case 3:
+ kf_bfly3(Fout, fstride, st, m);
+ break;
+ case 4:
+ kf_bfly4(Fout, fstride, st, m);
+ break;
+ case 5:
+ kf_bfly5(Fout, fstride, st, m);
+ break;
+ default:
+ kf_bfly_generic(Fout, fstride, st, m, p);
+ break;
+ }
+}
+
+/* facbuf is populated by p1,m1,p2,m2, ...
+ where
+ p[i] * m[i] = m[i-1]
+ m0 = n */
+static
+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 {+ while (n % p) {+ switch (p) {+ case 4:
+ p = 2;
+ break;
+ case 2:
+ p = 3;
+ break;
+ default:
+ p += 2;
+ break;
+ }
+ if (p > floor_sqrt)
+ p = n; /* no more factors, skip to end */
+ }
+ n /= p;
+ *facbuf++ = p;
+ *facbuf++ = n;
+ } while (n > 1);
+}
+
+/*
+ *
+ * User-callable function to allocate all necessary storage space for the fft.
+ *
+ * The return value is a contiguous block of memory, allocated with malloc. As such,
+ * It can be freed with free(), rather than a kiss_fft-specific function.
+ * */
+kiss_fft_cfg *kiss_fft_alloc(int nfft, int inverse_fft, void *mem, usize *lenmem) {+ kiss_fft_cfg *st = nil;
+ usize memneeded = sizeof(struct kiss_fft_state)
+ + sizeof(kiss_fft_cpx) * (nfft - 1); /* twiddle factors*/
+
+ if (lenmem == nil) {+ st = (kiss_fft_cfg*) KISS_FFT_MALLOC(memneeded);
+ } else {+ if (mem != nil && *lenmem >= memneeded)
+ st = (kiss_fft_cfg*) mem;
+ *lenmem = memneeded;
+ }
+ if (st) {+ int i;
+ st->nfft = nfft;
+ st->inverse = inverse_fft;
+
+ for (i = 0; i < nfft; ++i) {+ double phase = -2.0 * PI * ((double)i) / ((double)nfft);
+ if (st->inverse)
+ phase *= -1;
+ kf_cexp(st->twiddles + i, phase);
+ }
+
+ kf_factor(nfft, st->factors);
+ }
+ return st;
+}
+
+
+void kiss_fft_stride(kiss_fft_cfg *st, const kiss_fft_cpx *fin, kiss_fft_cpx *fout, int in_stride) {+ int j;
+ if (fin == fout) {+ //NOTE: this is not really an in-place FFT algorithm.
+ //It just performs an out-of-place FFT into a temp buffer
+ kiss_fft_cpx *tmpbuf = (kiss_fft_cpx *) KISS_FFT_TMP_ALLOC(sizeof(kiss_fft_cpx) * st->nfft);
+ kf_work(tmpbuf, fin, 1, in_stride, st->factors, st);
+ memcpy(fout, tmpbuf, sizeof(kiss_fft_cpx) * st->nfft);
+ KISS_FFT_TMP_FREE(tmpbuf);
+ } else {+ kf_work(fout, fin, 1, in_stride, st->factors, st);
+ }
+ if (st->inverse) {+ for (j = 0; j < st->nfft; j++) {+ fout[j].r /= st->nfft;
+ fout[j].i /= st->nfft;
+ }
+ }
+}
+
+void kiss_fft(kiss_fft_cfg *cfg, const kiss_fft_cpx *fin, kiss_fft_cpx *fout) {+ kiss_fft_stride(cfg, fin, fout, 1);
+}
+
+
+int kiss_fft_next_fast_size(int n) {+ while (1) {+ int m = n;
+ while ((m % 2) == 0) m /= 2;
+ while ((m % 3) == 0) m /= 3;
+ while ((m % 5) == 0) m /= 5;
+ if (m <= 1)
+ break; /* n is completely factorable by twos, threes, and fives */
+ n++;
+ }
+ return n;
+}
--- /dev/null
+++ b/kiss_fft.h
@@ -1,0 +1,95 @@
+#ifndef KISS_FFT_H
+#define KISS_FFT_H
+
+#ifdef __cplusplus
+extern "C" {+#endif
+
+#define KISS_FFT_MALLOC malloc
+#define KISS_FFT_FREE free
+
+
+#ifdef FIXED_POINT
+# if (FIXED_POINT == 32)
+# define kiss_fft_scalar s32int
+# else
+# define kiss_fft_scalar s16int
+# endif
+#else
+# ifndef kiss_fft_scalar
+/* default is double */
+# define kiss_fft_scalar double
+# endif
+#endif
+
+typedef struct {+ kiss_fft_scalar r;
+ kiss_fft_scalar i;
+}kiss_fft_cpx;
+
+typedef struct kiss_fft_state kiss_fft_cfg;
+#pragma incomplete kiss_fft_cfg
+
+/*
+ * kiss_fft_alloc
+ *
+ * Initialize a FFT (or IFFT) algorithm's cfg/state buffer.
+ *
+ * typical usage: kiss_fft_cfg *mycfg=kiss_fft_alloc(1024,0,NULL,NULL); for FFT
+ * kiss_fft_cfg *mycfg=kiss_fft_alloc(1024,1,NULL,NULL); for IFFT
+ *
+ * The return value from fft_alloc is a cfg buffer used internally
+ * by the fft routine or NULL.
+ *
+ * The inverse FFT is calculated if inverse_fft is non-zero.
+ *
+ * If lenmem is NULL, then kiss_fft_alloc will allocate a cfg buffer using malloc.
+ * The returned value should be free()d when done to avoid memory leaks.
+ *
+ * The state can be placed in a user supplied buffer 'mem':
+ * If lenmem is not NULL and mem is not NULL and *lenmem is large enough,
+ * then the function places the cfg in mem and the size used in *lenmem
+ * and returns mem.
+ *
+ * If lenmem is not NULL and ( mem is NULL or *lenmem is not large enough),
+ * then the function returns NULL and places the minimum cfg
+ * buffer size in *lenmem.
+ * */
+
+kiss_fft_cfg *kiss_fft_alloc(int nfft,int inverse_fft,void * mem, usize * lenmem);
+
+/*
+ * kiss_fft(cfg,in_out_buf)
+ *
+ * Perform an FFT on a complex input buffer.
+ * for a forward FFT,
+ * fin should be f[0] , f[1] , ... ,f[nfft-1]
+ * fout will be F[0] , F[1] , ... ,F[nfft-1]
+ * Note that each element is complex and can be accessed like
+ f[k].r and f[k].i
+ * */
+void kiss_fft(kiss_fft_cfg *cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout);
+
+/*
+ A more generic version of the above function. It reads its input from every Nth sample.
+ * */
+void kiss_fft_stride(kiss_fft_cfg *cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout,int fin_stride);
+
+/* If kiss_fft_alloc allocated a buffer, it is one contiguous
+ buffer and can be simply free()d when no longer needed*/
+#define kiss_fft_free free
+
+/*
+ * Returns the smallest integer k, such that k>=n and k has only "fast" factors (2,3,5)
+ */
+int kiss_fft_next_fast_size(int n);
+
+/* for real ffts, we need an even size */
+#define kiss_fftr_next_fast_size_real(n) \
+ (kiss_fft_next_fast_size( ((n)+1)>>1)<<1)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- /dev/null
+++ b/kiss_fftr.c
@@ -1,0 +1,159 @@
+/*
+Copyright (c) 2003-2004, Mark Borgerding
+Copyright (c) 2017, Bernd Porr
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+ * Neither the author nor the names of any contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <u.h>
+#include <libc.h>
+
+#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;
+};
+
+kiss_fftr_cfg *kiss_fftr_alloc(int nfft,int inverse_fft,void * mem,usize * lenmem)
+{+ int i;
+ kiss_fftr_cfg *st = nil;
+ usize subsize, memneeded;
+
+ if (nfft & 1) {+ fprint(2,"Real FFT optimization must be even.\n");
+ return nil;
+ }
+ nfft >>= 1;
+
+ kiss_fft_alloc (nfft, inverse_fft, nil, &subsize);
+ memneeded = sizeof(struct kiss_fftr_state) + subsize + sizeof(kiss_fft_cpx) * ( nfft * 3 / 2);
+
+ if (lenmem == nil) {+ st = (kiss_fftr_cfg*) KISS_FFT_MALLOC (memneeded);
+ } else {+ if (*lenmem >= memneeded)
+ st = (kiss_fftr_cfg*) mem;
+ *lenmem = memneeded;
+ }
+ if (!st)
+ return nil;
+
+ 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 =
+ -PI * ((double) (i+1) / nfft + .5);
+ if (inverse_fft)
+ phase *= -1;
+ kf_cexp (st->super_twiddles+i,phase);
+ }
+ return st;
+}
+
+int 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) {+ werrstr("improper alloc");+ return -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;
+ freqdata[ncfft].i = freqdata[0].i = 0;
+
+ 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);
+ }
+
+ return 0;
+}
+
+int 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) {+ werrstr("improper alloc");+ return -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);
+ st->tmpbuf[ncfft - k].i *= -1;
+ }
+ kiss_fft (st->substate, st->tmpbuf, (kiss_fft_cpx *) timedata);
+ for (k = 0; k < (ncfft * 2); k++) {+ timedata[k] /= 2;
+ }
+
+ return 0;
+}
--- /dev/null
+++ b/kiss_fftr.h
@@ -1,0 +1,46 @@
+#ifndef KISS_FTR_H
+#define KISS_FTR_H
+
+#include "kiss_fft.h"
+#ifdef __cplusplus
+extern "C" {+#endif
+
+
+/*
+
+ Real optimized version can save about 45% cpu time vs. complex fft of a real seq.
+
+
+
+ */
+
+typedef struct kiss_fftr_state kiss_fftr_cfg;
+#pragma incomplete kiss_fftr_cfg
+
+kiss_fftr_cfg *kiss_fftr_alloc(int nfft,int inverse_fft,void * mem, usize * lenmem);
+/*
+ nfft must be even
+
+ If you don't care to allocate space, use mem = lenmem = NULL
+*/
+
+
+int kiss_fftr(kiss_fftr_cfg *cfg,const kiss_fft_scalar *timedata,kiss_fft_cpx *freqdata);
+/*
+ input timedata has nfft scalar points
+ output freqdata has nfft/2+1 complex points
+*/
+
+int kiss_fftri(kiss_fftr_cfg *cfg,const kiss_fft_cpx *freqdata,kiss_fft_scalar *timedata);
+/*
+ input freqdata has nfft/2+1 complex points
+ output timedata has nfft scalar points
+*/
+
+#define kiss_fftr_free free
+
+#ifdef __cplusplus
+}
+#endif
+#endif
--- /dev/null
+++ b/mkfile
@@ -1,0 +1,19 @@
+</$objtype/mkfile
+
+BIN=/$objtype/bin/games
+CFLAGS=$CFLAGS -DFIXED_POINT=16 -p
+TARG=pitch
+
+HFILES=\
+ _kiss_fft_guts.h\
+ kiss_fft.h\
+ kiss_fftr.h\
+
+OFILES=\
+ kiss_fft.$O\
+ kiss_fftr.$O\
+ pitch.$O\
+
+default:V: all
+
+</sys/src/cmd/mkone
--- /dev/null
+++ b/pitch.c
@@ -1,0 +1,230 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <thread.h>
+#include <mouse.h>
+#include <keyboard.h>
+#include "kiss_fftr.h"
+
+typedef struct Note Note;
+
+struct Note {+ char *s;
+ Image **ct;
+ int f;
+ Image **cl;
+};
+
+static s16int window[2048];
+static kiss_fft_cpx freq[nelem(window)/2+1];
+static Image *ct, *ct2, *cl, *cl2, *cf;
+static Note notes[] = {+ {"A5", &ct, 880, &cl},+ {"G5", &ct2, 784, &cl2},+ {"F5", &ct2, 698, &cl2},+ {"E5", &ct2, 659, &cl2},+ {"D5", &ct2, 587, &cl2},+ {"C5", &ct2, 523, &cl2},+ {"B4", &ct2, 494, &cl2},+ {"A4", &ct, 440, &cl},+ {"G4", &ct2, 392, &cl2},+ {"F4", &ct2, 349, &cl2},+ {"E4", &ct2, 330, &cl2},+ {"D4", &ct2, 293, &cl2},+ {"C4", &ct2, 261, &cl2},+ {"B3", &ct2, 246, &cl2},+ {"A3", &ct, 220, &cl},+ {"G3", &ct2, 196, &cl2},+ {"F3", &ct2, 175, &cl2},+ {"E3", &ct2, 165, &cl2},+ {"D3", &ct2, 147, &cl2},+ {"C3", &ct2, 130, &cl2},+ {"B2", &ct2, 123, &cl2},+ {"A2", &ct, 110, &cl},+ {"A1", &ct, 55, &cl},+};
+
+#define last (nelem(notes)-1)
+
+static void
+redraw(int freq, int full)
+{+ static int w;
+ static double m;
+ static Image *data;
+ static Point p0;
+ static int nosignal;
+
+ int i, x, rx;
+ Rectangle r, dr;
+ Point p;
+ Font *f;
+
+ f = display->defaultfont;
+ r = screen->r;
+ r.min.x += stringwidth(f, " ");
+ r.min.y += f->height;
+ r.max.x -= stringwidth(f, " ");
+ r.max.y -= f->height*2;
+ rx = r.max.x;
+
+ p = r.min;
+
+ if(full){+ draw(screen, screen->r, display->black, nil, ZP);
+ freeimage(data);
+ data = allocimage(display, screen->r, RGB24, 0, DNofill);
+
+ w = 0;
+ for(i = 0; i < nelem(notes); i++){+ if(w < (x = 2*stringwidth(f, notes[0].s)))
+ w = x;
+ }
+ m = Dy(r) / fabs(notes[0].f - notes[last].f);
+ }
+
+ r.max.x -= w;
+
+ for(i = 0; i < nelem(notes); i++){+ p.y = r.min.y + m * fabs(notes[0].f - notes[i].f);
+ if(full)
+ string(screen, p, *notes[i].ct, ZP, f, notes[i].s);
+ line(
+ screen,
+ addpt(p, Pt(full ? w : r.max.x-p.x-1, f->height/2)),
+ addpt(p, Pt(r.max.x-p.x, f->height/2)),
+ Endsquare, Endsquare, 0,
+ *notes[i].cl,
+ ZP
+ );
+ if(full)
+ string(screen, Pt(rx-w/2, p.y), *notes[i].ct, ZP, f, notes[i].s);
+ }
+
+ if(freq <= notes[0].f && freq >= notes[last].f){+ nosignal = 0;
+ p = Pt(r.max.x - 1, r.min.y + m * fabs(notes[0].f - freq));
+ line(screen, p, p0.x ? p0 : addpt(p, Pt(1,0)), Endsquare, Endsquare, 0, cf, ZP);
+ p0 = p;
+ }else if(nosignal++ > 4){+ p0 = ZP;
+ }
+
+ dr = screen->r;
+ dr.min.x = -1;
+ dr.min.y = 0;
+ r.max.x++;
+ r.min.x += w;
+ replclipr(screen, 0, r);
+ draw(screen, dr, display->screenimage, nil, ZP);
+ flushimage(display, 1);
+ replclipr(screen, 0, screen->r);
+}
+
+static void
+usage(void)
+{+ fprint(2, "usage: %s [/dev/audio]\n", argv0);
+ threadexitsall("usage");+}
+
+void
+threadmain(int argc, char **argv)
+{+ int f, n, i, x, ox[8], max, avg;
+ kiss_fftr_cfg *c;
+ Keyboardctl *kctl;
+ Mousectl *mctl;
+ Mouse m;
+ Rune r;
+
+ enum {+ Ckey,
+ Cmouse,
+ Cresize,
+ Numchan,
+ };
+ Alt a[Numchan+1] = {+ [Ckey] = { nil, &r, CHANRCV },+ [Cmouse] = { nil, &m, CHANRCV },+ [Cresize] = { nil, nil, CHANRCV },+ { nil, nil, CHANNOBLK },+ };
+
+ ARGBEGIN{+ default:
+ usage();
+ }ARGEND
+
+ if(argc > 1)
+ usage();
+
+ if((f = open(argc ? argv[0] : "/dev/audio", OREAD)) < 0)
+ sysfatal("%r");+ if((c = kiss_fftr_alloc(nelem(window), 0, nil, nil)) == nil)
+ sysfatal("failed to get fft config");+
+ if(initdraw(nil, nil, "pitch") < 0)
+ sysfatal("initdraw: %r");+ if ((mctl = initmouse(nil, screen)) == nil)
+ sysfatal("initmouse: %r");+ if((kctl = initkeyboard(nil)) == nil)
+ sysfatal("initkeyboard: %r");+ a[Ckey].c = kctl->c;
+ a[Cmouse].c = mctl->c;
+ a[Cresize].c = mctl->resizec;
+ threadsetname("pitch");+ ct = display->white;
+ ct2 = allocimage(display, Rect(0,0,1,1), RGB24, 1, DWhite/3);
+ cl = allocimage(display, Rect(0,0,1,1), RGB24, 1, DGreen);
+ cl2 = allocimage(display, Rect(0,0,1,1), RGB24, 1, DGreen/3);
+ cf = allocimage(display, Rect(0,0,1,1), RGB24, 1, DYellow);
+
+ redraw(0, 1);
+
+ memset(ox, 0, sizeof(ox));
+ for(;;){+ if((n = readn(f, window, sizeof(window))) < 0)
+ sysfatal("%r");+ if(n == 0)
+ break;
+ if(kiss_fftr(c, window, freq) != 0)
+ sysfatal("%r");+ for(i = 0, x = 0, max = 5, avg = 0; i < nelem(freq); i++){+ if(freq[i].r > max){+ x = (44100/nelem(freq))*i/2;
+ max = freq[i].r;
+ }
+ avg += freq[i].r;
+ }
+ avg /= i;
+ if(max > avg+5){+ ox[0] = x;
+ for(i = x = 0; i < nelem(ox); i++)
+ x += ox[i];
+ x /= nelem(ox);
+ memmove(ox+1, ox, sizeof(ox)-sizeof(ox[0]));
+ }else{+ x = 0;
+ }
+
+ switch(alt(a)){+ case Ckey:
+ if(r == Kdel || r == 'q')
+ goto done;
+ break;
+ case Cmouse:
+ break;
+ case Cresize:
+ getwindow(display, Refnone);
+ redraw(x, 1);
+ continue;
+ }
+
+ redraw(x, 0);
+ }
+
+done:
+ kiss_fftr_free(c);
+ threadexitsall(nil);
+}
binary files /dev/null b/trans.png differ