diff options
Diffstat (limited to 'usr.bin/aucat')
| -rw-r--r-- | usr.bin/aucat/dsp.c | 127 | ||||
| -rw-r--r-- | usr.bin/aucat/dsp.h | 31 |
2 files changed, 149 insertions, 9 deletions
diff --git a/usr.bin/aucat/dsp.c b/usr.bin/aucat/dsp.c index 3e8a1006690..dd36a25058b 100644 --- a/usr.bin/aucat/dsp.c +++ b/usr.bin/aucat/dsp.c @@ -1,4 +1,4 @@ -/* $OpenBSD: dsp.c,v 1.14 2020/12/10 17:20:39 ratchov Exp $ */ +/* $OpenBSD: dsp.c,v 1.15 2021/01/11 14:45:51 ratchov Exp $ */ /* * Copyright (c) 2008-2012 Alexandre Ratchov <alex@caoua.org> * @@ -108,6 +108,75 @@ short dec_alawmap[256] = { 944, 912, 1008, 976, 816, 784, 880, 848 }; +int resamp_filt[RESAMP_LENGTH / RESAMP_STEP + 1] = { + 0, 0, 3, 9, 22, 42, 73, 116, + 174, 248, 341, 454, 589, 749, 934, 1148, + 1392, 1666, 1974, 2316, 2693, 3107, 3560, 4051, + 4582, 5154, 5766, 6420, 7116, 7853, 8632, 9451, + 10311, 11210, 12148, 13123, 14133, 15178, 16253, 17359, + 18491, 19647, 20824, 22018, 23226, 24443, 25665, 26888, + 28106, 29315, 30509, 31681, 32826, 33938, 35009, 36033, + 37001, 37908, 38744, 39502, 40174, 40750, 41223, 41582, + 41819, 41925, 41890, 41704, 41358, 40842, 40147, 39261, + 38176, 36881, 35366, 33623, 31641, 29411, 26923, 24169, + 21140, 17827, 14222, 10317, 6105, 1580, -3267, -8440, + -13944, -19785, -25967, -32492, -39364, -46584, -54153, -62072, + -70339, -78953, -87911, -97209, -106843, -116806, -127092, -137692, + -148596, -159795, -171276, -183025, -195029, -207271, -219735, -232401, + -245249, -258259, -271407, -284670, -298021, -311434, -324880, -338329, + -351750, -365111, -378378, -391515, -404485, -417252, -429775, -442015, + -453930, -465477, -476613, -487294, -497472, -507102, -516137, -524527, + -532225, -539181, -545344, -550664, -555090, -558571, -561055, -562490, + -562826, -562010, -559990, -556717, -552139, -546205, -538866, -530074, + -519779, -507936, -494496, -479416, -462652, -444160, -423901, -401835, + -377923, -352132, -324425, -294772, -263143, -229509, -193847, -156134, + -116348, -74474, -30494, 15601, 63822, 114174, 166661, 221283, + 278037, 336916, 397911, 461009, 526194, 593446, 662741, 734054, + 807354, 882608, 959779, 1038826, 1119706, 1202370, 1286768, 1372846, + 1460546, 1549808, 1640566, 1732753, 1826299, 1921130, 2017169, 2114336, + 2212550, 2311723, 2411770, 2512598, 2614116, 2716228, 2818836, 2921841, + 3025142, 3128636, 3232218, 3335782, 3439219, 3542423, 3645282, 3747687, + 3849526, 3950687, 4051059, 4150530, 4248987, 4346320, 4442415, 4537163, + 4630453, 4722177, 4812225, 4900493, 4986873, 5071263, 5153561, 5233668, + 5311485, 5386917, 5459872, 5530259, 5597992, 5662986, 5725160, 5784436, + 5840739, 5893999, 5944148, 5991122, 6034862, 6075313, 6112422, 6146142, + 6176430, 6203247, 6226559, 6246335, 6262551, 6275185, 6284220, 6289647, + 6291456, 6289647, 6284220, 6275185, 6262551, 6246335, 6226559, 6203247, + 6176430, 6146142, 6112422, 6075313, 6034862, 5991122, 5944148, 5893999, + 5840739, 5784436, 5725160, 5662986, 5597992, 5530259, 5459872, 5386917, + 5311485, 5233668, 5153561, 5071263, 4986873, 4900493, 4812225, 4722177, + 4630453, 4537163, 4442415, 4346320, 4248987, 4150530, 4051059, 3950687, + 3849526, 3747687, 3645282, 3542423, 3439219, 3335782, 3232218, 3128636, + 3025142, 2921841, 2818836, 2716228, 2614116, 2512598, 2411770, 2311723, + 2212550, 2114336, 2017169, 1921130, 1826299, 1732753, 1640566, 1549808, + 1460546, 1372846, 1286768, 1202370, 1119706, 1038826, 959779, 882608, + 807354, 734054, 662741, 593446, 526194, 461009, 397911, 336916, + 278037, 221283, 166661, 114174, 63822, 15601, -30494, -74474, + -116348, -156134, -193847, -229509, -263143, -294772, -324425, -352132, + -377923, -401835, -423901, -444160, -462652, -479416, -494496, -507936, + -519779, -530074, -538866, -546205, -552139, -556717, -559990, -562010, + -562826, -562490, -561055, -558571, -555090, -550664, -545344, -539181, + -532225, -524527, -516137, -507102, -497472, -487294, -476613, -465477, + -453930, -442015, -429775, -417252, -404485, -391515, -378378, -365111, + -351750, -338329, -324880, -311434, -298021, -284670, -271407, -258259, + -245249, -232401, -219735, -207271, -195029, -183025, -171276, -159795, + -148596, -137692, -127092, -116806, -106843, -97209, -87911, -78953, + -70339, -62072, -54153, -46584, -39364, -32492, -25967, -19785, + -13944, -8440, -3267, 1580, 6105, 10317, 14222, 17827, + 21140, 24169, 26923, 29411, 31641, 33623, 35366, 36881, + 38176, 39261, 40147, 40842, 41358, 41704, 41890, 41925, + 41819, 41582, 41223, 40750, 40174, 39502, 38744, 37908, + 37001, 36033, 35009, 33938, 32826, 31681, 30509, 29315, + 28106, 26888, 25665, 24443, 23226, 22018, 20824, 19647, + 18491, 17359, 16253, 15178, 14133, 13123, 12148, 11210, + 10311, 9451, 8632, 7853, 7116, 6420, 5766, 5154, + 4582, 4051, 3560, 3107, 2693, 2316, 1974, 1666, + 1392, 1148, 934, 749, 589, 454, 341, 248, + 174, 116, 73, 42, 22, 9, 3, 0, + 0 +}; + + /* * Generate a string corresponding to the encoding in par, * return the length of the resulting string. @@ -309,8 +378,10 @@ resamp_do(struct resamp *p, adata_t *in, adata_t *out, int icnt, int ocnt) unsigned int iblksz; unsigned int ofr; unsigned int c; + int64_t f[NCHAN_MAX]; adata_t *ctxbuf, *ctx; unsigned int ctx_start; + int q, qi, qf, n; /* * Partially copy structures into local variables, to avoid @@ -346,7 +417,7 @@ resamp_do(struct resamp *p, adata_t *in, adata_t *out, int icnt, int ocnt) if (diff >= oblksz) { if (ifr == 0) break; - ctx_start ^= 1; + ctx_start = (ctx_start - 1) & (RESAMP_NCTX - 1); ctx = ctxbuf + ctx_start; for (c = nch; c > 0; c--) { *ctx = *idata++; @@ -357,13 +428,48 @@ resamp_do(struct resamp *p, adata_t *in, adata_t *out, int icnt, int ocnt) } else { if (ofr == 0) break; - ctx = ctxbuf; + + for (c = nch; c > 0; c--) + f[c] = 0; + + q = diff * p->filt_step; + n = ctx_start; + + while (q < RESAMP_LENGTH) { + qi = q >> RESAMP_STEP_BITS; + qf = q & (RESAMP_STEP - 1); + s = resamp_filt[qi]; + ds = resamp_filt[qi + 1] - s; + s += (int64_t)qf * ds >> RESAMP_STEP_BITS; + ctx = ctxbuf; + for (c = nch; c > 0; c--) { + f[c] += (int64_t)ctx[n] * s; + ctx += RESAMP_NCTX; + } + q += p->filt_cutoff; + n = (n + 1) & (RESAMP_NCTX - 1); + } + for (c = nch; c > 0; c--) { - s = ctx[ctx_start ^ 1]; - ds = ctx[ctx_start] - s; - ctx += RESAMP_NCTX; - *odata++ = s + ADATA_MULDIV(ds, diff, oblksz); + s = f[c] >> RESAMP_BITS; + s = (int64_t)s * p->filt_cutoff >> RESAMP_BITS; +#if ADATA_BITS == 16 + /* + * In 16-bit mode, we've no room for filter + * overshoots, so we need to clip the signal + * to avoid 16-bit integers to wrap around. + * In 24-bit mode, samples may exceed the + * [-1:1] range. Later, cmap_add() will clip + * them, so no need to clip them here as well. + */ + if (s >= ADATA_UNIT) + s = ADATA_UNIT - 1; + else if (s < -ADATA_UNIT) + s = -ADATA_UNIT; +#endif + *odata++ = s; } + diff += iblksz; ofr--; } @@ -429,6 +535,13 @@ resamp_init(struct resamp *p, unsigned int iblksz, p->nch = nch; p->ctx_start = 0; memset(p->ctx, 0, sizeof(p->ctx)); + if (p->iblksz < p->oblksz) { + p->filt_cutoff = RESAMP_UNIT; + p->filt_step = RESAMP_UNIT / p->oblksz; + } else { + p->filt_cutoff = (int64_t)RESAMP_UNIT * p->oblksz / p->iblksz; + p->filt_step = RESAMP_UNIT / p->iblksz; + } #ifdef DEBUG if (log_level >= 3) { log_puts("resamp: "); diff --git a/usr.bin/aucat/dsp.h b/usr.bin/aucat/dsp.h index a7a0a01df24..267ae2138de 100644 --- a/usr.bin/aucat/dsp.h +++ b/usr.bin/aucat/dsp.h @@ -1,4 +1,4 @@ -/* $OpenBSD: dsp.h,v 1.5 2016/06/08 04:36:48 ratchov Exp $ */ +/* $OpenBSD: dsp.h,v 1.6 2021/01/11 14:45:51 ratchov Exp $ */ /* * Copyright (c) 2012 Alexandre Ratchov <alex@caoua.org> * @@ -92,6 +92,32 @@ typedef int adata_t; #endif /* + * The FIR is sampled and stored in a table of fixed-point numbers + * with 23 fractional bits. For convenience, we use the same fixed-point + * numbers to represent time and to walk through the table. + */ +#define RESAMP_BITS 23 +#define RESAMP_UNIT (1 << RESAMP_BITS) + +/* + * Filter window length (the time unit is RESAMP_UNIT) + */ +#define RESAMP_LENGTH (8 * RESAMP_UNIT) + +/* + * Time between samples of the FIR (the time unit is RESAMP_UNIT) + */ +#define RESAMP_STEP_BITS (RESAMP_BITS - 6) +#define RESAMP_STEP (1 << RESAMP_STEP_BITS) + +/* + * Maximum downsample/upsample ratio we support, must be a power of two. + * The ratio between the max and the min sample rates is 192kHz / 4kHz = 48, + * so we can use 64 + */ +#define RESAMP_RATIO 64 + +/* * Maximum size of the encording string (the longest possible * encoding is ``s24le3msb''). */ @@ -111,9 +137,10 @@ struct aparams { }; struct resamp { -#define RESAMP_NCTX 2 +#define RESAMP_NCTX (RESAMP_LENGTH / RESAMP_UNIT * RESAMP_RATIO) unsigned int ctx_start; adata_t ctx[NCHAN_MAX * RESAMP_NCTX]; + int filt_cutoff, filt_step; unsigned int iblksz, oblksz; int diff; int nch; |