code: plan9front

Download patch

ref: 2d1f4327f1f81cfdc57c491f3f3bdc2a325dfe60
parent: 0d84321e6555a4650d142f181f21d8950b7794de
author: Sigrid Solveig Haflínudóttir <sigrid@ftrv.se>
date: Wed Mar 27 19:43:06 EDT 2024

audio/pcmconv: use libpcm

--- a/sys/src/cmd/audio/pcmconv/fir.h
+++ /dev/null
@@ -1,131 +1,0 @@
-/*
- * FIR filter coefficients from resample-1.x smallfilter.h 
- * see Digital Audio Resampling Home Page located at
- * http://ccrma.stanford.edu/~jos/resample/
- */
-32767, 32766, 32764, 32760, 32755, 32749, 32741, 32731, 32721, 32708,
-32695, 32679, 32663, 32645, 32625, 32604, 32582, 32558, 32533, 32506,
-32478, 32448, 32417, 32385, 32351, 32316, 32279, 32241, 32202, 32161,
-32119, 32075, 32030, 31984, 31936, 31887, 31836, 31784, 31731, 31676,
-31620, 31563, 31504, 31444, 31383, 31320, 31256, 31191, 31124, 31056,
-30987, 30916, 30845, 30771, 30697, 30621, 30544, 30466, 30387, 30306,
-30224, 30141, 30057, 29971, 29884, 29796, 29707, 29617, 29525, 29433,
-29339, 29244, 29148, 29050, 28952, 28852, 28752, 28650, 28547, 28443,
-28338, 28232, 28125, 28017, 27908, 27797, 27686, 27574, 27461, 27346,
-27231, 27115, 26998, 26879, 26760, 26640, 26519, 26398, 26275, 26151,
-26027, 25901, 25775, 25648, 25520, 25391, 25262, 25131, 25000, 24868,
-24735, 24602, 24467, 24332, 24197, 24060, 23923, 23785, 23647, 23507,
-23368, 23227, 23086, 22944, 22802, 22659, 22515, 22371, 22226, 22081,
-21935, 21789, 21642, 21494, 21346, 21198, 21049, 20900, 20750, 20600,
-20449, 20298, 20146, 19995, 19842, 19690, 19537, 19383, 19230, 19076,
-18922, 18767, 18612, 18457, 18302, 18146, 17990, 17834, 17678, 17521,
-17365, 17208, 17051, 16894, 16737, 16579, 16422, 16264, 16106, 15949,
-15791, 15633, 15475, 15317, 15159, 15001, 14843, 14685, 14527, 14369,
-14212, 14054, 13896, 13739, 13581, 13424, 13266, 13109, 12952, 12795,
-12639, 12482, 12326, 12170, 12014, 11858, 11703, 11548, 11393, 11238,
-11084, 10929, 10776, 10622, 10469, 10316, 10164, 10011, 9860, 9708,
-9557, 9407, 9256, 9106, 8957, 8808, 8659, 8511, 8364, 8216, 8070,
-7924, 7778, 7633, 7488, 7344, 7200, 7057, 6914, 6773, 6631, 6490,
-6350, 6210, 6071, 5933, 5795, 5658, 5521, 5385, 5250, 5115, 4981,
-4848, 4716, 4584, 4452, 4322, 4192, 4063, 3935, 3807, 3680, 3554,
-3429, 3304, 3180, 3057, 2935, 2813, 2692, 2572, 2453, 2335, 2217,
-2101, 1985, 1870, 1755, 1642, 1529, 1418, 1307, 1197, 1088, 979, 872,
-765, 660, 555, 451, 348, 246, 145, 44, -54, -153, -250, -347, -443,
--537, -631, -724, -816, -908, -998, -1087, -1175, -1263, -1349, -1435,
--1519, -1603, -1685, -1767, -1848, -1928, -2006, -2084, -2161, -2237,
--2312, -2386, -2459, -2531, -2603, -2673, -2742, -2810, -2878, -2944,
--3009, -3074, -3137, -3200, -3261, -3322, -3381, -3440, -3498, -3554,
--3610, -3665, -3719, -3772, -3824, -3875, -3925, -3974, -4022, -4069,
--4116, -4161, -4205, -4249, -4291, -4333, -4374, -4413, -4452, -4490,
--4527, -4563, -4599, -4633, -4666, -4699, -4730, -4761, -4791, -4820,
--4848, -4875, -4901, -4926, -4951, -4974, -4997, -5019, -5040, -5060,
--5080, -5098, -5116, -5133, -5149, -5164, -5178, -5192, -5205, -5217,
--5228, -5238, -5248, -5257, -5265, -5272, -5278, -5284, -5289, -5293,
--5297, -5299, -5301, -5303, -5303, -5303, -5302, -5300, -5298, -5295,
--5291, -5287, -5282, -5276, -5270, -5263, -5255, -5246, -5237, -5228,
--5217, -5206, -5195, -5183, -5170, -5157, -5143, -5128, -5113, -5097,
--5081, -5064, -5047, -5029, -5010, -4991, -4972, -4952, -4931, -4910,
--4889, -4867, -4844, -4821, -4797, -4774, -4749, -4724, -4699, -4673,
--4647, -4620, -4593, -4566, -4538, -4510, -4481, -4452, -4422, -4393,
--4363, -4332, -4301, -4270, -4238, -4206, -4174, -4142, -4109, -4076,
--4042, -4009, -3975, -3940, -3906, -3871, -3836, -3801, -3765, -3729,
--3693, -3657, -3620, -3584, -3547, -3510, -3472, -3435, -3397, -3360,
--3322, -3283, -3245, -3207, -3168, -3129, -3091, -3052, -3013, -2973,
--2934, -2895, -2855, -2816, -2776, -2736, -2697, -2657, -2617, -2577,
--2537, -2497, -2457, -2417, -2377, -2337, -2297, -2256, -2216, -2176,
--2136, -2096, -2056, -2016, -1976, -1936, -1896, -1856, -1817, -1777,
--1737, -1698, -1658, -1619, -1579, -1540, -1501, -1462, -1423, -1384,
--1345, -1306, -1268, -1230, -1191, -1153, -1115, -1077, -1040, -1002,
--965, -927, -890, -854, -817, -780, -744, -708, -672, -636, -600,
--565, -530, -494, -460, -425, -391, -356, -322, -289, -255, -222,
--189, -156, -123, -91, -59, -27, 4, 35, 66, 97, 127, 158, 188, 218,
-247, 277, 306, 334, 363, 391, 419, 447, 474, 501, 528, 554, 581, 606,
-632, 657, 683, 707, 732, 756, 780, 803, 827, 850, 872, 895, 917, 939,
-960, 981, 1002, 1023, 1043, 1063, 1082, 1102, 1121, 1139, 1158, 1176,
-1194, 1211, 1228, 1245, 1262, 1278, 1294, 1309, 1325, 1340, 1354,
-1369, 1383, 1397, 1410, 1423, 1436, 1448, 1461, 1473, 1484, 1496,
-1507, 1517, 1528, 1538, 1548, 1557, 1566, 1575, 1584, 1592, 1600,
-1608, 1616, 1623, 1630, 1636, 1643, 1649, 1654, 1660, 1665, 1670,
-1675, 1679, 1683, 1687, 1690, 1694, 1697, 1700, 1702, 1704, 1706,
-1708, 1709, 1711, 1712, 1712, 1713, 1713, 1713, 1713, 1712, 1711,
-1710, 1709, 1708, 1706, 1704, 1702, 1700, 1697, 1694, 1691, 1688,
-1685, 1681, 1677, 1673, 1669, 1664, 1660, 1655, 1650, 1644, 1639,
-1633, 1627, 1621, 1615, 1609, 1602, 1596, 1589, 1582, 1575, 1567,
-1560, 1552, 1544, 1536, 1528, 1520, 1511, 1503, 1494, 1485, 1476,
-1467, 1458, 1448, 1439, 1429, 1419, 1409, 1399, 1389, 1379, 1368,
-1358, 1347, 1337, 1326, 1315, 1304, 1293, 1282, 1271, 1260, 1248,
-1237, 1225, 1213, 1202, 1190, 1178, 1166, 1154, 1142, 1130, 1118,
-1106, 1094, 1081, 1069, 1057, 1044, 1032, 1019, 1007, 994, 981, 969,
-956, 943, 931, 918, 905, 892, 879, 867, 854, 841, 828, 815, 802, 790,
-777, 764, 751, 738, 725, 713, 700, 687, 674, 662, 649, 636, 623, 611,
-598, 585, 573, 560, 548, 535, 523, 510, 498, 486, 473, 461, 449, 437,
-425, 413, 401, 389, 377, 365, 353, 341, 330, 318, 307, 295, 284, 272,
-261, 250, 239, 228, 217, 206, 195, 184, 173, 163, 152, 141, 131, 121,
-110, 100, 90, 80, 70, 60, 51, 41, 31, 22, 12, 3, -5, -14, -23, -32,
--41, -50, -59, -67, -76, -84, -93, -101, -109, -117, -125, -133, -140,
--148, -156, -163, -170, -178, -185, -192, -199, -206, -212, -219,
--226, -232, -239, -245, -251, -257, -263, -269, -275, -280, -286,
--291, -297, -302, -307, -312, -317, -322, -327, -332, -336, -341,
--345, -349, -354, -358, -362, -366, -369, -373, -377, -380, -384,
--387, -390, -394, -397, -400, -402, -405, -408, -411, -413, -416,
--418, -420, -422, -424, -426, -428, -430, -432, -433, -435, -436,
--438, -439, -440, -442, -443, -444, -445, -445, -446, -447, -447,
--448, -448, -449, -449, -449, -449, -449, -449, -449, -449, -449,
--449, -449, -448, -448, -447, -447, -446, -445, -444, -443, -443,
--442, -441, -440, -438, -437, -436, -435, -433, -432, -430, -429,
--427, -426, -424, -422, -420, -419, -417, -415, -413, -411, -409,
--407, -405, -403, -400, -398, -396, -393, -391, -389, -386, -384,
--381, -379, -376, -374, -371, -368, -366, -363, -360, -357, -355,
--352, -349, -346, -343, -340, -337, -334, -331, -328, -325, -322,
--319, -316, -313, -310, -307, -304, -301, -298, -294, -291, -288,
--285, -282, -278, -275, -272, -269, -265, -262, -259, -256, -252,
--249, -246, -243, -239, -236, -233, -230, -226, -223, -220, -217,
--213, -210, -207, -204, -200, -197, -194, -191, -187, -184, -181,
--178, -175, -172, -168, -165, -162, -159, -156, -153, -150, -147,
--143, -140, -137, -134, -131, -128, -125, -122, -120, -117, -114,
--111, -108, -105, -102, -99, -97, -94, -91, -88, -86, -83, -80, -78,
--75, -72, -70, -67, -65, -62, -59, -57, -55, -52, -50, -47, -45, -43,
--40, -38, -36, -33, -31, -29, -27, -25, -22, -20, -18, -16, -14, -12,
--10, -8, -6, -4, -2, 0, 0, 2, 4, 6, 8, 9, 11, 13, 14, 16, 17, 19, 21,
-22, 24, 25, 27, 28, 29, 31, 32, 33, 35, 36, 37, 38, 40, 41, 42, 43,
-44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59,
-59, 60, 61, 62, 62, 63, 63, 64, 64, 65, 66, 66, 66, 67, 67, 68, 68,
-69, 69, 69, 70, 70, 70, 70, 71, 71, 71, 71, 71, 72, 72, 72, 72, 72,
-72, 72, 72, 72, 72, 72, 72, 72, 72, 72, 72, 72, 72, 72, 72, 72, 72,
-72, 71, 71, 71, 71, 71, 70, 70, 70, 70, 69, 69, 69, 69, 68, 68, 68,
-67, 67, 67, 66, 66, 66, 65, 65, 64, 64, 64, 63, 63, 62, 62, 62, 61,
-61, 60, 60, 59, 59, 58, 58, 58, 57, 57, 56, 56, 55, 55, 54, 54, 53,
-53, 52, 52, 51, 51, 50, 50, 49, 48, 48, 47, 47, 46, 46, 45, 45, 44,
-44, 43, 43, 42, 42, 41, 41, 40, 39, 39, 38, 38, 37, 37, 36, 36, 35,
-35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 29, 29, 28, 28, 27, 27,
-26, 26, 25, 25, 24, 24, 23, 23, 23, 22, 22, 21, 21, 20, 20, 20, 19,
-19, 18, 18, 17, 17, 17, 16, 16, 15, 15, 15, 14, 14, 14, 13, 13, 12,
-12, 12, 11, 11, 11, 10, 10, 10, 9, 9, 9, 9, 8, 8, 8, 7, 7, 7, 7, 6, 6,
-6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 1, 1, 1,
-1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -1,
--1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -2, -2, -2, -2, -2, -2, -2,
--2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
--2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
--2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
--2, -2, -2, -2, -2, -2, -2, -2, -1, -1, -1, -1, -1, -1, -1, -1, -1,
--1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
--- a/sys/src/cmd/audio/pcmconv/pcmconv.c
+++ b/sys/src/cmd/audio/pcmconv/pcmconv.c
@@ -1,596 +1,8 @@
 #include <u.h>
 #include <libc.h>
+#include <pcm.h>
 
-typedef struct Desc Desc;
-typedef struct Chan Chan;
-
-struct Desc
-{
-	int	rate;
-	int	channels;
-	int	framesz;
-	int	abits;	/* bits after input conversion */
-	int	bits;	/* bits in input stream per sample */
-	Rune	fmt;
-};
-
-struct Chan
-{
-	ulong	ρ;	/* factor */
-
-	ulong	t;	/* time */
-
-	ulong	tΔ;	/* output step */
-	ulong	lΔ;	/* filter step */
-	ulong	le;	/* filter end */
-
-	int	u;	/* unity scale */
-	int	*h;	/* filter coefficients */
-	int	*hΔ;	/* coefficient deltas for interpolation */
-
-	int	wx;	/* extra samples */
-	int	ix;	/* buffer index */
-	int	nx;	/* buffer size */
-	int	*x;	/* the buffer */
-};
-
-enum {
-	Nl	= 8,		/* 2^Nl samples per zero crossing in fir */
-	Nη	= 8,		/* phase bits for filter interpolation */
-	Np	= Nl+Nη,	/* phase bits (fract of fixed point) */
-	One	= 1<<Np,
-};
-
-#define MAXINT	((int)(~0UL>>1))
-#define MININT	(MAXINT+1)
-
-int
-clip(vlong v)
-{
-	if(v > MAXINT)
-		return MAXINT;
-	if(v < MININT)
-		return MININT;
-	return v;
-}
-
-int
-chaninit(Chan *c, int irate, int orate, int count)
-{
-	static int h[] = {
-#include "fir.h"
-	};
-	static int hΔ[nelem(h)], init = 0;
-	int n;
-
-	c->ρ = ((uvlong)orate<<Np)/irate;
-	if(c->ρ == One)
-		goto Done;
-
-	c->tΔ = ((uvlong)irate<<Np)/orate;
-	c->lΔ = 1<<(Nl+Nη);
-	c->le = nelem(h)<<Nη;
-	c->wx = 1 + (c->le / c->lΔ);
-	c->u = 13128;	/* unity scale factor for fir */
-	if(c->ρ < One){
-		c->u *= c->ρ;
-		c->u >>= Np;
-		c->lΔ *= c->ρ;
-		c->lΔ >>= Np;
-		c->wx *= c->tΔ;
-		c->wx >>= Np;
-	}
-	if(!init){
-		init = 1;
-		for(n=0; n<nelem(hΔ)-1; n++)
-			hΔ[n] = h[n+1] - h[n];
-	}
-	c->h = h;
-	c->hΔ = hΔ;
-	c->ix = c->wx;
-	c->t = c->ix<<Np;
-	c->nx = c->wx*2 + count;
-	c->x = sbrk(sizeof(c->x[0]) * c->nx);
-	count += c->nx; /* account for buffer accumulation */
-Done:
-	return ((uvlong)count * c->ρ) >> Np;
-}
-
-int
-filter(Chan *c)
-{
-	ulong l, lΔ, le, p, i;
-	int *x, *h, *hΔ, a;
-	vlong v;
-
-	v = 0;
-
-	h = c->h;
-	hΔ = c->hΔ;
-	lΔ = c->lΔ;
-	le = c->le;
-
-	/* left side */
-	x = &c->x[c->t>>Np];
-	p = c->t & ((1<<Np)-1);
-	l = c->ρ < One ? (c->ρ * p)>>Np : p;
-	while(l < le){
-		i = l >> Nη;
-		a = l & ((1<<Nη)-1);
-		l += lΔ;
-		a *= hΔ[i];
-		a >>= Nη;
-		a += h[i];
-		v += (vlong)*(--x) * a;
-	}
-
-	/* right side */
-	x = &c->x[c->t>>Np];
-	p = (One - p) & ((1<<Np)-1);
-	l = c->ρ < One ? (c->ρ * p)>>Np : p;
-	if(p == 0) /* skip h[0] as it was already been summed above if p == 0 */
-		l += c->lΔ;
-	while(l < le){
-		i = l >> Nη;
-		a = l & ((1<<Nη)-1);
-		l += lΔ;
-		a *= hΔ[i];
-		a >>= Nη;
-		a += h[i];
-		v += (vlong)*x++ * a;
-	}
-
-	/* scale */
-	v >>= 2;
-	v *= c->u;
-	v >>= 27;
-
-	return clip(v);
-}
-
-int*
-resample(Chan *c, int *x, int *y, int count)
-{
-	ulong e;
-	int i, n;
-
-	if(c->ρ == One){
-		/* no rate conversion needed */
-		if(count > 0)
-			memmove(y, x, count*sizeof(int));
-		return y+count;
-	}
-
-	if(count == 0){
-		/* stuff zeros to drain last samples out */
-		while(c->ix < 2*c->wx)
-			c->x[c->ix++] = 0;
-	}
-
-	do {
-		/* fill buffer */
-		for(i = c->ix, n = c->nx; count > 0 && i < n; count--, i++)
-			c->x[i] = *x++;
-		c->ix = i;
-
-		/* need at least 2*wx samples in buffer for filter */
-		if(i < 2*c->wx)
-			break;
-
-		/* process buffer */
-		e = (i - c->wx)<<Np;
-		while(c->t < e){
-			*y++ = filter(c);
-			c->t += c->tΔ;
-		}
-
-		/* check if we'r at the end of buffer and wrap it */
-		e = c->t >> Np;
-		if(e >= (c->nx - c->wx)){
-			c->t -= e << Np;
-			c->t += c->wx << Np;
-			n = c->t >> Np;
-			n -= c->wx;
-			e -= c->wx;
-			i -= e;
-			if(i > 0){
-				memmove(c->x + n, c->x + e, i*sizeof(int));
-				n += i;
-			}
-			c->ix = n;
-		}
-	} while(count > 0);
-
-	return y;
-}
-
-void
-dither(int *y, int ibits, int obits, int count)
-{
-	static ulong prnd;
-
-	if(ibits >= 32 || obits >= ibits)
-		return;
-
-	while(count--){
-		prnd = (prnd*0x19660dL + 0x3c6ef35fL) & 0xffffffffL;
-		*y = clip((vlong)*y + ((int)prnd >> ibits));
-		y++;
-	}
-}
-
-void
-mixin(int *y, int *x, int count)
-{
-	while(count--){
-		*y = clip((vlong)*y + *x++);
-		y++;
-	}
-}
-
-void
-siconv(int *dst, uchar *src, int bits, int skip, int count)
-{
-	int i, v, s, b;
-
-	b = (bits+7)/8;
-	s = sizeof(int)*8-bits;
-	while(count--){
-		v = 0;
-		i = b;
-		switch(b){
-		case 4:
-			v = src[--i];
-		case 3:
-			v = (v<<8) | src[--i];
-		case 2:
-			v = (v<<8) | src[--i];
-		case 1:
-			v = (v<<8) | src[--i];
-		}
-		*dst++ = v << s;
-		src += skip;
-	}
-}
-
-void
-Siconv(int *dst, uchar *src, int bits, int skip, int count)
-{
-	int i, v, s, b;
-
-	b = (bits+7)/8;
-	s = sizeof(int)*8-bits;
-	while(count--){
-		v = 0;
-		i = 0;
-		switch(b){
-		case 4:
-			v = src[i++];
-		case 3:
-			v = (v<<8) | src[i++];
-		case 2:
-			v = (v<<8) | src[i++];
-		case 1:
-			v = (v<<8) | src[i];
-		}
-		*dst++ = v << s;
-		src += skip;
-	}
-}
-
-void
-uiconv(int *dst, uchar *src, int bits, int skip, int count)
-{
-	int i, s, b;
-	uint v;
-
-	b = (bits+7)/8;
-	s = sizeof(uint)*8-bits;
-	while(count--){
-		v = 0;
-		i = b;
-		switch(b){
-		case 4:
-			v = src[--i];
-		case 3:
-			v = (v<<8) | src[--i];
-		case 2:
-			v = (v<<8) | src[--i];
-		case 1:
-			v = (v<<8) | src[--i];
-		}
-		*dst++ = (v << s) - (~0UL>>1);
-		src += skip;
-	}
-}
-
-void
-Uiconv(int *dst, uchar *src, int bits, int skip, int count)
-{
-	int i, s, b;
-	uint v;
-
-	b = (bits+7)/8;
-	s = sizeof(uint)*8-bits;
-	while(count--){
-		v = 0;
-		i = 0;
-		switch(b){
-		case 4:
-			v = src[i++];
-		case 3:
-			v = (v<<8) | src[i++];
-		case 2:
-			v = (v<<8) | src[i++];
-		case 1:
-			v = (v<<8) | src[i];
-		}
-		*dst++ = (v << s) - (~0UL>>1);
-		src += skip;
-	}
-}
-
-void
-ficonv(int *dst, uchar *src, int bits, int skip, int count)
-{
-	if(bits == 32){
-		while(count--){
-			float f;
-
-			f = *((float*)src), src += skip;
-			if(f > 1.0)
-				*dst++ = MAXINT;
-			else if(f < -1.0)
-				*dst++ = MININT;
-			else
-				*dst++ = f*((float)MAXINT);
-		}
-	} else {
-		while(count--){
-			double d;
-
-			d = *((double*)src), src += skip;
-			if(d > 1.0)
-				*dst++ = MAXINT;
-			else if(d < -1.0)
-				*dst++ = MININT;
-			else
-				*dst++ = d*((double)MAXINT);
-		}
-	}
-}
-
-void
-aiconv(int *dst, uchar *src, int, int skip, int count)
-{
-	int t, seg;
-	uchar a;
-
-	while(count--){
-		a = *src, src += skip;
-		a ^= 0x55;
-		t = (a & 0xf) << 4;
-		seg = (a & 0x70) >> 4;
-		switch(seg){
-		case 0:
-			t += 8;
-			break;
-		case 1:
-			t += 0x108;
-			break;
-		default:
-			t += 0x108;
-			t <<= seg - 1;
-		}
-		t = (a & 0x80) ? t : -t;
-		*dst++ = t << (sizeof(int)*8 - 16);
-	}
-}
-
-void
-µiconv(int *dst, uchar *src, int, int skip, int count)
-{
-	int t;
-	uchar u;
-
-	while(count--){
-		u = *src, src += skip;
-		u = ~u;
-		t = ((u & 0xf) << 3) + 0x84;
-		t <<= (u & 0x70) >> 4;
-		t = u & 0x80 ? 0x84 - t: t - 0x84;
-		*dst++ = t << (sizeof(int)*8 - 16);
-	}
-}
-
-void
-soconv(int *src, uchar *dst, int bits, int skip, int count)
-{
-	int i, v, s, b;
-
-	b = (bits+7)/8;
-	s = sizeof(int)*8-bits;
-	while(count--){
-		v = *src++ >> s;
-		i = 0;
-		switch(b){
-		case 4:
-			dst[i++] = v, v >>= 8;
-		case 3:
-			dst[i++] = v, v >>= 8;
-		case 2:
-			dst[i++] = v, v >>= 8;
-		case 1:
-			dst[i] = v;
-		}
-		dst += skip;
-	}
-}
-
-void
-Soconv(int *src, uchar *dst, int bits, int skip, int count)
-{
-	int i, v, s, b;
-
-	b = (bits+7)/8;
-	s = sizeof(int)*8-bits;
-	while(count--){
-		v = *src++ >> s;
-		i = b;
-		switch(b){
-		case 4:
-			dst[--i] = v, v >>= 8;
-		case 3:
-			dst[--i] = v, v >>= 8;
-		case 2:
-			dst[--i] = v, v >>= 8;
-		case 1:
-			dst[--i] = v;
-		}
-		dst += skip;
-	}
-}
-
-void
-uoconv(int *src, uchar *dst, int bits, int skip, int count)
-{
-	int i, s, b;
-	uint v;
-
-	b = (bits+7)/8;
-	s = sizeof(uint)*8-bits;
-	while(count--){
-		v = ((~0UL>>1) + *src++) >> s;
-		i = 0;
-		switch(b){
-		case 4:
-			dst[i++] = v, v >>= 8;
-		case 3:
-			dst[i++] = v, v >>= 8;
-		case 2:
-			dst[i++] = v, v >>= 8;
-		case 1:
-			dst[i] = v;
-		}
-		dst += skip;
-	}
-}
-
-void
-Uoconv(int *src, uchar *dst, int bits, int skip, int count)
-{
-	int i, s, b;
-	uint v;
-
-	b = (bits+7)/8;
-	s = sizeof(uint)*8-bits;
-	while(count--){
-		v = ((~0UL>>1) + *src++) >> s;
-		i = b;
-		switch(b){
-		case 4:
-			dst[--i] = v, v >>= 8;
-		case 3:
-			dst[--i] = v, v >>= 8;
-		case 2:
-			dst[--i] = v, v >>= 8;
-		case 1:
-			dst[--i] = v;
-		}
-		dst += skip;
-	}
-}
-
-void
-foconv(int *src, uchar *dst, int bits, int skip, int count)
-{
-	if(bits == 32){
-		while(count--){
-			*((float*)dst) = *src++ / ((float)MAXINT);
-			dst += skip;
-		}
-	} else {
-		while(count--){
-			*((double*)dst) = *src++ / ((double)MAXINT);
-			dst += skip;
-		}
-	}
-}
-
-Desc
-mkdesc(char *f)
-{
-	Desc d;
-	Rune r;
-	char *p;
-
-	memset(&d, 0, sizeof(d));
-	p = f;
-	while(*p != 0){
-		p += chartorune(&r, p);
-		switch(r){
-		case L'r':
-			d.rate = strtol(p, &p, 10);
-			break;
-		case L'c':
-			d.channels = strtol(p, &p, 10);
-			break;
-		case L'm':
-			r = L'µ';
-		case L's':
-		case L'S':
-		case L'u':
-		case L'U':
-		case L'f':
-		case L'a':
-		case L'µ':
-			d.fmt = r;
-			d.bits = d.abits = strtol(p, &p, 10);
-			break;
-		default:
-			goto Bad;
-		}
-	}
-	if(d.rate <= 0)
-		goto Bad;
-	if(d.fmt == L'a' || d.fmt == L'µ'){
-		if(d.bits != 8)
-			goto Bad;
-		d.abits = 16;
-	} else if(d.fmt == L'f'){
-		if(d.bits != 32 && d.bits != 64)
-			goto Bad;
-		d.abits = sizeof(int)*8;
-	} else if(d.bits <= 0 || d.bits > 32)
-		goto Bad;
-	d.framesz = ((d.bits+7)/8) * d.channels;
-	if(d.framesz <= 0)
-		goto Bad;
-	return d;
-Bad:
-	sysfatal("bad format: %s", f);
-}
-
-int
-cread(int fd, uchar *buf, int len, int mod)
-{
-	uchar *off = buf;
-
-	len -= (len % mod);
-Again:
-	len = read(fd, off, len);
-	if(len <= 0)
-		return len;
-	off += len;
-	len = off - buf;
-	if((len % mod) != 0){
-		len = mod - (len % mod);
-		goto Again;
-	}
-	return len;
-}
-
-void
+static void
 usage(void)
 {
 	fprint(2, "usage: %s [-i fmt] [-o fmt] [-l length]\n", argv0);
@@ -601,24 +13,22 @@
 main(int argc, char *argv[])
 {
 	uchar ibuf[8*1024], *obuf;
-	int *out, *in;
-	Chan ch[8];
-	Desc i, o;
-	int k, n, m, nin, nout;
+	Pcmdesc i, o;
+	Pcmconv *c;
 	vlong l;
+	int n;
 
-	void (*oconv)(int *, uchar *, int, int, int);
-	void (*iconv)(int *, uchar *, int, int, int);
-
-	o = mkdesc("s16c2r44100");
-	i = o;
+	i = pcmdescdef;
+	o = pcmdescdef;
 	l = -1LL;
 	ARGBEGIN {
 	case 'i':
-		i = mkdesc(EARGF(usage()));
+		if(mkpcmdesc(EARGF(usage()), &i) < 0)
+			sysfatal("%r");
 		break;
 	case 'o':
-		o = mkdesc(EARGF(usage()));
+		if(mkpcmdesc(EARGF(usage()), &o) < 0)
+			sysfatal("%r");
 		break;
 	case 'l':
 		l = atoll(EARGF(usage()));
@@ -627,104 +37,28 @@
 		usage();
 	} ARGEND;
 
-	/* check if same format */
-	if(i.rate == o.rate
-	&& i.bits == o.bits
-	&& i.channels == o.channels
-	&& i.framesz == o.framesz
-	&& i.fmt == o.fmt){
-		while((n = read(0, ibuf, sizeof(ibuf))) > 0){
-			if(write(1, ibuf, n) != n)
-				sysfatal("write: %r");
-		}
-		if(n < 0)
-			sysfatal("read: %r");
-		exits(0);
-	}
+	if((c = allocpcmconv(&i, &o)) == nil)
+		sysfatal("%r");
+	if((n = pcmratio(c, sizeof(ibuf))) < 0)
+		sysfatal("%r");
+	obuf = malloc(n);
 
-	if(i.channels > nelem(ch))
-		sysfatal("too many input channels: %d", i.channels);
-
-	switch(i.fmt){
-	case L's': iconv = siconv; break;
-	case L'S': iconv = Siconv; break;
-	case L'u': iconv = uiconv; break;
-	case L'U': iconv = Uiconv; break;
-	case L'f': iconv = ficonv; break;
-	case L'a': iconv = aiconv; break;
-	case L'µ': iconv = µiconv; break;
-	default:
-		sysfatal("unsupported input format: %C", i.fmt);
-	}
-
-	switch(o.fmt){
-	case L's': oconv = soconv; break;
-	case L'S': oconv = Soconv; break;
-	case L'u': oconv = uoconv; break;
-	case L'U': oconv = Uoconv; break;
-	case L'f': oconv = foconv; break;
-	default:
-		sysfatal("unsupported output format: %C", o.fmt);
-	}
-
-	if(i.fmt == L'f' || o.fmt == L'f')
-		setfcr(getfcr() & ~(FPINVAL|FPOVFL));
-
-	nin = (sizeof(ibuf)-i.framesz)/i.framesz;
-	in = sbrk(sizeof(int) * nin);
-
-	nout = 0;
-	memset(ch, 0, sizeof(ch));
-	for(k=0; k < i.channels; k++)
-		nout = chaninit(&ch[k], i.rate, o.rate, nin);
-
-	/* out is also used for mixing before resampling, so needs to be max(nin, nout) */
-	out = sbrk(sizeof(int) * (nout>nin? nout: nin));
-	obuf = sbrk(o.framesz * nout);
-
 	for(;;){
-		n = nin * i.framesz;
+		n = sizeof(ibuf);
 		if(l >= 0 && l < n)
 			n = l;
-		n = cread(0, ibuf, n, i.framesz);
+		n = read(0, ibuf, n);
 		if(n < 0)
 			sysfatal("read: %r");
 		if(l > 0)
 			l -= n;
-		n /= i.framesz;
-		(*iconv)(in, ibuf, i.bits, i.framesz, n);
-		if(i.channels > o.channels){
-			for(k=1; k<i.channels; k++){
-				(*iconv)(out, ibuf + k*((i.bits+7)/8), i.bits, i.framesz, n);
-				mixin(in, out, n);
-			}
-		}
-		dither(in, i.abits, o.abits, n);
-		m = resample(&ch[0], in, out, n) - out;
-		if(m < 1){
-			if(n == 0)
-				break;
-		} else
-			(*oconv)(out, obuf, o.bits, o.framesz, m);
-		if(i.channels == o.channels){
-			for(k=1; k<i.channels; k++){
-				(*iconv)(in, ibuf + k*((i.bits+7)/8), i.bits, i.framesz, n);
-				dither(in, i.abits, o.abits, n);
-				resample(&ch[k], in, out, n);
-				if(m > 0)
-					(*oconv)(out, obuf + k*((o.bits+7)/8), o.bits, o.framesz, m);
-			}
-		} else if(m > 0){
-			for(k=1; k<o.channels; k++)
-				(*oconv)(out, obuf + k*((o.bits+7)/8), o.bits, o.framesz, m);
-		}
-		if(m > 0){
-			m *= o.framesz;
-			if(write(1, obuf, m) != m)
+		n = pcmconv(c, ibuf, obuf, n);
+		if(n > 0){
+			if(write(1, obuf, n) != n)
 				sysfatal("write: %r");
 		}
 		if(n == 0)
 			break;
 	}
-	exits(0);
+	exits(nil);
 }