Return to aproc.c CVS log

Up to [local] / src / usr.bin / aucat

When resampling, don't require the sample frequency to be an integer.
This removes the arithmetic constraint between the sample frequency
and the block size and all the associated code. Now aucat can work
in server mode with any block size.
ok jakemsr

/*	$OpenBSD: aproc.c,v 1.26 2008/12/07 17:10:41 ratchov Exp $	*/
/*
 * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
/*
 * aproc structures are simple audio processing units. They are
 * interconnected by abuf structures and form a kind of circuit. aproc
 * structure have call-backs that do the actual processing.
 *
 * This module implements the following processing units:
 *
 *  - rpipe: read end of an unix file (pipe, socket, device...)
 *
 *  - wpipe: write end of an unix file (pipe, socket, device...)
 *
 *  - mix: mix N inputs -> 1 output
 *
 *  - sub: from 1 input -> extract/copy N outputs
 *
 *  - conv: converts/resamples/remaps a single stream
 *
 *  - resamp: resample streams in native format
 *
 * TODO
 *
 * 	(easy) split the "conv" into 2 converters: one for input (that
 *	convers anything to 16bit signed) and one for the output (that
 *	converts 16bit signed to anything)
 *
 *	(hard) add a lowpass filter for the resampler. Quality is
 *	not acceptable as is.
 *
 */
#include <err.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "conf.h"
#include "aparams.h"
#include "abuf.h"
#include "aproc.h"
#include "file.h"

struct aproc *
aproc_new(struct aproc_ops *ops, char *name)
{
	struct aproc *p;

	p = malloc(sizeof(struct aproc));
	if (p == NULL)
		err(1, name);
	LIST_INIT(&p->ibuflist);
	LIST_INIT(&p->obuflist);
	p->name = name;
	p->ops = ops;
	return p;
}

void
aproc_del(struct aproc *p)
{
	struct abuf *i;

	DPRINTF("aproc_del: %s(%s): terminating...\n", p->ops->name, p->name);

	if (p->ops->done)
		p->ops->done(p);

	while (!LIST_EMPTY(&p->ibuflist)) {
		i = LIST_FIRST(&p->ibuflist);
		abuf_hup(i);
	}
	while (!LIST_EMPTY(&p->obuflist)) {
		i = LIST_FIRST(&p->obuflist);
		abuf_eof(i);
	}
	DPRINTF("aproc_del: %s(%s): freed\n", p->ops->name, p->name);
	free(p);
}

void
aproc_setin(struct aproc *p, struct abuf *ibuf)
{
	LIST_INSERT_HEAD(&p->ibuflist, ibuf, ient);
	ibuf->rproc = p;
	if (p->ops->newin)
		p->ops->newin(p, ibuf);
}

void
aproc_setout(struct aproc *p, struct abuf *obuf)
{
	LIST_INSERT_HEAD(&p->obuflist, obuf, oent);
	obuf->wproc = p;
	if (p->ops->newout)
		p->ops->newout(p, obuf);
}

void
aproc_ipos(struct aproc *p, struct abuf *ibuf, int delta)
{
	struct abuf *obuf;

	DPRINTFN(3, "aproc_ipos: %s: delta = %d\n", p->name, delta);

	LIST_FOREACH(obuf, &p->obuflist, oent) {
		abuf_ipos(obuf, delta);
	}
}

void
aproc_opos(struct aproc *p, struct abuf *obuf, int delta)
{
	struct abuf *ibuf;

	DPRINTFN(3, "aproc_opos: %s: delta = %d\n", p->name, delta);

	LIST_FOREACH(ibuf, &p->ibuflist, ient) {
		abuf_opos(ibuf, delta);
	}
}

int
rpipe_in(struct aproc *p, struct abuf *ibuf_dummy)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);
	struct file *f = p->u.io.file;
	unsigned char *data;
	unsigned count;

	DPRINTFN(3, "rpipe_in: %s\n", p->name);

	if (ABUF_FULL(obuf) || !(f->state & FILE_ROK))
		return 0;
	data = abuf_wgetblk(obuf, &count, 0);
	count = file_read(f, data, count);
	if (count == 0)
		return 0;
	abuf_wcommit(obuf, count);
	if (!abuf_flush(obuf))
		return 0;
	return 1;
}

int
rpipe_out(struct aproc *p, struct abuf *obuf)
{
	struct file *f = p->u.io.file;
	unsigned char *data;
	unsigned count;

	if (f->refs > 0)
		return 0;
	DPRINTFN(3, "rpipe_out: %s\n", p->name);
	
	if (ABUF_FULL(obuf) || !(f->state & FILE_ROK))
		return 0;
	data = abuf_wgetblk(obuf, &count, 0);
	count = file_read(f, data, count);
	if (count == 0)
		return 0;
	abuf_wcommit(obuf, count);
	return 1;
}

void
rpipe_done(struct aproc *p)
{
	struct file *f = p->u.io.file;

	f->rproc = NULL;
	if (f->wproc == NULL)
		file_del(f);
}

void
rpipe_eof(struct aproc *p, struct abuf *ibuf_dummy)
{
	DPRINTFN(3, "rpipe_eof: %s\n", p->name);
	aproc_del(p);
}

void
rpipe_hup(struct aproc *p, struct abuf *obuf)
{
	DPRINTFN(3, "rpipe_hup: %s\n", p->name);
	aproc_del(p);
}

struct aproc_ops rpipe_ops = {
	"rpipe",
	rpipe_in,
	rpipe_out,
	rpipe_eof,
	rpipe_hup,
	NULL, /* newin */
	NULL, /* newout */
	aproc_ipos,
	aproc_opos,
	rpipe_done
};

struct aproc *
rpipe_new(struct file *f)
{
	struct aproc *p;

	p = aproc_new(&rpipe_ops, f->name);
	p->u.io.file = f;
	f->rproc = p;	
	return p;
}

void
wpipe_done(struct aproc *p)
{
	struct file *f = p->u.io.file;

	f->wproc = NULL;
	if (f->rproc == NULL)
		file_del(f);
}

int
wpipe_in(struct aproc *p, struct abuf *ibuf)
{
	struct file *f = p->u.io.file;
	unsigned char *data;
	unsigned count;

	if (f->refs > 0)
		return 0;
	DPRINTFN(3, "wpipe_in: %s\n", p->name);

	if (ABUF_EMPTY(ibuf) || !(f->state & FILE_WOK))
		return 0;
	data = abuf_rgetblk(ibuf, &count, 0);
	count = file_write(f, data, count);
	if (count == 0)
		return 0;
	abuf_rdiscard(ibuf, count);
	return 1;
}

int
wpipe_out(struct aproc *p, struct abuf *obuf_dummy)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);
	struct file *f = p->u.io.file;
	unsigned char *data;
	unsigned count;

	DPRINTFN(3, "wpipe_out: %s\n", p->name);

	if (!abuf_fill(ibuf)) {
		DPRINTFN(3, "wpipe_out: fill failed\n");       
		return 0;
	}
	if (ABUF_EMPTY(ibuf) || !(f->state & FILE_WOK))
		return 0;
	data = abuf_rgetblk(ibuf, &count, 0);
	if (count == 0) {
		DPRINTF("wpipe_out: %s: underrun\n", p->name);
		return 0;
	}
	count = file_write(f, data, count);
	if (count == 0)
		return 0;
	abuf_rdiscard(ibuf, count);
	return 1;
}

void
wpipe_eof(struct aproc *p, struct abuf *ibuf)
{
	DPRINTFN(3, "wpipe_eof: %s\n", p->name);
	aproc_del(p);
}

void
wpipe_hup(struct aproc *p, struct abuf *obuf_dummy)
{
	DPRINTFN(3, "wpipe_hup: %s\n", p->name);
	aproc_del(p);
}

struct aproc_ops wpipe_ops = {
	"wpipe",
	wpipe_in,
	wpipe_out,
	wpipe_eof,
	wpipe_hup,
	NULL, /* newin */
	NULL, /* newout */
	aproc_ipos,
	aproc_opos,
	wpipe_done
};

struct aproc *
wpipe_new(struct file *f)
{
	struct aproc *p;

	p = aproc_new(&wpipe_ops, f->name);
	p->u.io.file = f;
	f->wproc = p;
	return p;
}

/*
 * Fill an output block with silence.
 */
void
mix_bzero(struct aproc *p)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);
	short *odata;
	unsigned ocount;

	DPRINTFN(4, "mix_bzero: used = %u, todo = %u\n",
	    obuf->used, obuf->mixitodo);
	odata = (short *)abuf_wgetblk(obuf, &ocount, obuf->mixitodo);
	ocount -= ocount % obuf->bpf;
	if (ocount == 0)
		return;
	memset(odata, 0, ocount);
	obuf->mixitodo += ocount;
	DPRINTFN(4, "mix_bzero: ocount %u, todo %u\n", ocount, obuf->mixitodo);
}

/*
 * Mix an input block over an output block.
 */
void
mix_badd(struct abuf *ibuf, struct abuf *obuf)
{
	short *idata, *odata;
	unsigned i, j, icnt, onext, ostart;
	unsigned scount, icount, ocount;
	int vol;

	DPRINTFN(4, "mix_badd: todo = %u, done = %u\n",
	    obuf->mixitodo, ibuf->mixodone);

	idata = (short *)abuf_rgetblk(ibuf, &icount, 0);
	icount /= ibuf->bpf;
	if (icount == 0)
		return;

	odata = (short *)abuf_wgetblk(obuf, &ocount, ibuf->mixodone);
	ocount /= obuf->bpf;
	if (ocount == 0)
		return;

	vol = (ibuf->mixweight * ibuf->mixvol) >> ADATA_SHIFT;
	ostart = ibuf->cmin - obuf->cmin; 
	onext = obuf->cmax - ibuf->cmax + ostart;
	icnt = ibuf->cmax - ibuf->cmin + 1;
	odata += ostart;
	scount = (icount < ocount) ? icount : ocount;
	for (i = scount; i > 0; i--) {
		for (j = icnt; j > 0; j--) {
			*odata += (*idata * vol) >> ADATA_SHIFT;
			idata++;
			odata++;
		}
		odata += onext;
	}
	abuf_rdiscard(ibuf, scount * ibuf->bpf);
	ibuf->mixodone += scount * obuf->bpf;

	DPRINTFN(4, "mix_badd: added %u, done = %u, todo = %u\n",
	    scount, ibuf->mixodone, obuf->mixitodo);
}

int
mix_in(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *i, *inext, *obuf = LIST_FIRST(&p->obuflist);
	unsigned ocount;

	DPRINTFN(4, "mix_in: used = %u, done = %u, todo = %u\n",
	    ibuf->used, ibuf->mixodone, obuf->mixitodo);
		
	if (!ABUF_ROK(ibuf) || ibuf->mixodone == obuf->mixitodo)
		return 0;

	mix_badd(ibuf, obuf);
	ocount = obuf->mixitodo;
	LIST_FOREACH(i, &p->ibuflist, ient) {
		if (ocount > i->mixodone)
			ocount = i->mixodone;
	}
	if (ocount == 0)
		return 0;

	abuf_wcommit(obuf, ocount);
	p->u.mix.lat += ocount / obuf->bpf;
	obuf->mixitodo -= ocount;
	if (!abuf_flush(obuf))
		return 0; /* hup */
	mix_bzero(p);
	for (i = LIST_FIRST(&p->ibuflist); i != NULL; i = inext) {
		inext = LIST_NEXT(i, ient);
		i->mixodone -= ocount;
		if (i->mixodone < obuf->mixitodo)
			mix_badd(i, obuf);
		if (!abuf_fill(i))
			continue;
	}
	if (LIST_EMPTY(&p->ibuflist))
		p->u.mix.idle += ocount / obuf->bpf;
	return 1;
}

int
mix_out(struct aproc *p, struct abuf *obuf)
{
	struct abuf *i, *inext;
	unsigned ocount, fdrop;

	DPRINTFN(4, "mix_out: used = %u, todo = %u\n",
	    obuf->used, obuf->mixitodo);

	if (!ABUF_WOK(obuf))
		return 0;

	mix_bzero(p);
	ocount = obuf->mixitodo;
	for (i = LIST_FIRST(&p->ibuflist); i != NULL; i = inext) {
		inext = LIST_NEXT(i, ient);
		if (!abuf_fill(i))
			continue;
		if (!ABUF_ROK(i)) {
			if ((p->u.mix.flags & MIX_DROP) && i->mixodone == 0) {
				if (i->xrun == XRUN_ERROR) {
					abuf_hup(i);
					continue;
				}
				fdrop = obuf->mixitodo / obuf->bpf;
				i->mixodone += fdrop * obuf->bpf;
				if (i->xrun == XRUN_SYNC)
					i->drop += fdrop * i->bpf;
				else {
					abuf_opos(i, -(int)fdrop);
					if (i->duplex) {
						DPRINTF("mix_out: duplex %u\n",
						    fdrop);
						i->duplex->drop += fdrop * 
						    i->duplex->bpf;
						abuf_ipos(i->duplex,
						    -(int)fdrop);
					}
				}
				DPRINTF("mix_out: drop = %u\n", i->drop);
			}
		} else
			mix_badd(i, obuf);
		if (ocount > i->mixodone)
			ocount = i->mixodone;
	}
	if (ocount == 0)
		return 0;
	if (LIST_EMPTY(&p->ibuflist) && (p->u.mix.flags & MIX_AUTOQUIT)) {
		DPRINTF("mix_out: nothing more to do...\n");
		aproc_del(p);
		return 0;
	}
	abuf_wcommit(obuf, ocount);
	p->u.mix.lat += ocount / obuf->bpf;
	obuf->mixitodo -= ocount;
	LIST_FOREACH(i, &p->ibuflist, ient) {
		i->mixodone -= ocount;
	}
	if (LIST_EMPTY(&p->ibuflist))
		p->u.mix.idle += ocount / obuf->bpf;
	return 1;
}

void
mix_eof(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);

	DPRINTF("mix_eof: %s: detached\n", p->name);
	mix_setmaster(p);

	/*
	 * If there's no more inputs, abuf_run() will trigger the eof
	 * condition and propagate it, so no need to handle it here.
	 */
	abuf_run(obuf);
	DPRINTF("mix_eof: done\n");
}

void
mix_hup(struct aproc *p, struct abuf *obuf)
{
	struct abuf *ibuf;

	while (!LIST_EMPTY(&p->ibuflist)) {
		ibuf = LIST_FIRST(&p->ibuflist);
		abuf_hup(ibuf);
	}
	DPRINTF("mix_hup: %s: done\n", p->name);
	aproc_del(p);
}

void
mix_newin(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);

	if (!obuf || ibuf->cmin < obuf->cmin || ibuf->cmax > obuf->cmax) {
		fprintf(stderr, "mix_newin: channel ranges mismatch\n");
		abort();
	}
	p->u.mix.idle = 0;
	ibuf->mixodone = 0;
	ibuf->mixvol = ADATA_UNIT;
	ibuf->mixweight = ADATA_UNIT;
	ibuf->mixmaxweight = ADATA_UNIT;
	ibuf->xrun = XRUN_IGNORE;
}

void
mix_newout(struct aproc *p, struct abuf *obuf)
{
	DPRINTF("mix_newout: using %u fpb\n", obuf->len / obuf->bpf);
	obuf->mixitodo = 0;
	mix_bzero(p);
}

void
mix_opos(struct aproc *p, struct abuf *obuf, int delta)
{
	DPRINTFN(3, "mix_opos: lat = %d/%d\n", p->u.mix.lat, p->u.mix.maxlat);
	p->u.mix.lat -= delta;
	aproc_opos(p, obuf, delta);
}

struct aproc_ops mix_ops = {
	"mix",
	mix_in,
	mix_out,
	mix_eof,
	mix_hup,
	mix_newin,
	mix_newout,
	aproc_ipos,
	mix_opos,
	NULL
};

struct aproc *
mix_new(char *name, int maxlat)
{
	struct aproc *p;

	p = aproc_new(&mix_ops, name);
	p->u.mix.flags = 0;
	p->u.mix.idle = 0;
	p->u.mix.lat = 0;
	p->u.mix.maxlat = maxlat;
	return p;
}

void
mix_pushzero(struct aproc *p)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);

	abuf_wcommit(obuf, obuf->mixitodo);
	p->u.mix.lat += obuf->mixitodo / obuf->bpf;
	obuf->mixitodo = 0;
	abuf_run(obuf);
	mix_bzero(p);
}

/*
 * Normalize input levels
 */
void
mix_setmaster(struct aproc *p)
{
	unsigned n;
	struct abuf *buf;
	int weight;

	n = 0;
	LIST_FOREACH(buf, &p->ibuflist, ient) {
		n++;
	}
	LIST_FOREACH(buf, &p->ibuflist, ient) {
		weight = ADATA_UNIT / n;
		if (weight > buf->mixmaxweight)
			weight = buf->mixmaxweight;
		buf->mixweight = weight;
		DPRINTF("mix_setmaster: %p: %d/%d -> %d\n", buf,
		    buf->mixweight, buf->mixmaxweight, weight);
	}
}

void
mix_clear(struct aproc *p)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);

	p->u.mix.lat = 0;
	obuf->mixitodo = 0;
	mix_bzero(p);
}

/*
 * Copy data from ibuf to obuf.
 */
void
sub_bcopy(struct abuf *ibuf, struct abuf *obuf)
{
	short *idata, *odata;
	unsigned i, j, ocnt, inext, istart;
	unsigned icount, ocount, scount;

	idata = (short *)abuf_rgetblk(ibuf, &icount, obuf->subidone);
	icount /= ibuf->bpf;
	if (icount == 0)
		return;
	odata = (short *)abuf_wgetblk(obuf, &ocount, 0);
	ocount /= obuf->bpf;
	if (ocount == 0)
		return;
	istart = obuf->cmin - ibuf->cmin;
	inext = ibuf->cmax - obuf->cmax + istart;
	ocnt = obuf->cmax - obuf->cmin + 1;
	scount = (icount < ocount) ? icount : ocount;
	idata += istart;
	for (i = scount; i > 0; i--) {
		for (j = ocnt; j > 0; j--) {
			*odata = *idata;
			odata++;
			idata++;
		}
		idata += inext;
	}
	abuf_wcommit(obuf, scount * obuf->bpf);	
	obuf->subidone += scount * ibuf->bpf;
	DPRINTFN(4, "sub_bcopy: %u frames\n", scount);
}

int
sub_in(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *i, *inext;
	unsigned done, fdrop;
	
	if (!ABUF_ROK(ibuf))
		return 0;
	done = ibuf->used;
	for (i = LIST_FIRST(&p->obuflist); i != NULL; i = inext) {
		inext = LIST_NEXT(i, oent);
		if (!ABUF_WOK(i)) {
			if ((p->u.sub.flags & SUB_DROP) && i->subidone == 0) {
				if (i->xrun == XRUN_ERROR) {
					abuf_eof(i);
					continue;
				}
				fdrop = ibuf->used / ibuf->bpf;
				if (i->xrun == XRUN_SYNC)
					i->silence += fdrop * i->bpf;
				else {
					abuf_ipos(i, -(int)fdrop);
					if (i->duplex) {
						DPRINTF("sub_in: duplex %u\n",
						    fdrop);
						i->duplex->silence += fdrop *
						    i->duplex->bpf;
						abuf_opos(i->duplex, 
						    -(int)fdrop);
					}
				}
				i->subidone += fdrop * ibuf->bpf;
				DPRINTF("sub_in: silence = %u\n", i->silence);
			}
		} else
			sub_bcopy(ibuf, i);
		if (done > i->subidone)
			done = i->subidone;
		if (!abuf_flush(i))
			continue;
	}
	LIST_FOREACH(i, &p->obuflist, oent) {
		i->subidone -= done;
	}
	abuf_rdiscard(ibuf, done);
	p->u.sub.lat -= done / ibuf->bpf;
	if (LIST_EMPTY(&p->obuflist))
		p->u.sub.idle += done / ibuf->bpf;
	return 1;
}

int
sub_out(struct aproc *p, struct abuf *obuf)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);
	struct abuf *i, *inext;
	unsigned done;

	if (!ABUF_WOK(obuf))
		return 0;
	if (!abuf_fill(ibuf)) {
		return 0;
	}
	if (obuf->subidone == ibuf->used)
		return 0;

	done = ibuf->used;
	for (i = LIST_FIRST(&p->obuflist); i != NULL; i = inext) {
		inext = LIST_NEXT(i, oent);
		if (!abuf_flush(i))
			continue;
		sub_bcopy(ibuf, i);
		if (done > i->subidone)
			done = i->subidone;
	}
	LIST_FOREACH(i, &p->obuflist, oent) {
		i->subidone -= done;
	}
	abuf_rdiscard(ibuf, done);
	p->u.sub.lat -= done / ibuf->bpf;
	if (LIST_EMPTY(&p->obuflist))
		p->u.sub.idle += done / ibuf->bpf;
	return 1;
}

void
sub_eof(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *obuf;

	while (!LIST_EMPTY(&p->obuflist)) {
		obuf = LIST_FIRST(&p->obuflist);
		abuf_eof(obuf);
	}
	aproc_del(p);
}

void
sub_hup(struct aproc *p, struct abuf *obuf)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);

	DPRINTF("sub_hup: %s: detached\n", p->name);
	abuf_run(ibuf);
	DPRINTF("sub_hup: done\n");
}

void
sub_newout(struct aproc *p, struct abuf *obuf)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);

	if (!ibuf || obuf->cmin < ibuf->cmin || obuf->cmax > ibuf->cmax) {
		fprintf(stderr, "sub_newout: channel ranges mismatch\n");
		abort();
	}
	p->u.sub.idle = 0;
	obuf->subidone = 0;
	obuf->xrun = XRUN_IGNORE;
}

void
sub_ipos(struct aproc *p, struct abuf *ibuf, int delta)
{
	p->u.sub.lat += delta;
	DPRINTFN(3, "sub_ipos: lat = %d/%d\n", p->u.sub.lat, p->u.sub.maxlat);
	aproc_ipos(p, ibuf, delta);
}

struct aproc_ops sub_ops = {
	"sub",
	sub_in,
	sub_out,
	sub_eof,
	sub_hup,
	NULL,
	sub_newout,
	sub_ipos,
	aproc_opos,
	NULL
};

struct aproc *
sub_new(char *name, int maxlat)
{
	struct aproc *p;

	p = aproc_new(&sub_ops, name);
	p->u.sub.flags = 0;
	p->u.sub.idle = 0;
	p->u.sub.lat = 0;
	p->u.sub.maxlat = maxlat;
	return p;
}

void
sub_clear(struct aproc *p)
{
	p->u.mix.lat = 0;
}

/*
 * Convert one block.
 */
void
resamp_bcopy(struct aproc *p, struct abuf *ibuf, struct abuf *obuf)
{
	unsigned inch;
	short *idata;
	unsigned ipos, oblksz;
	unsigned ifr;
	unsigned onch;
	short *odata;
	unsigned opos, iblksz;
	unsigned ofr;
	unsigned c;
	short *ctxbuf, *ctx;
	unsigned icount, ocount;

	/*
	 * Calculate max frames readable at once from the input buffer.
	 */
	idata = (short *)abuf_rgetblk(ibuf, &icount, 0);
	ifr = icount / ibuf->bpf;
	icount = ifr * ibuf->bpf;

	odata = (short *)abuf_wgetblk(obuf, &ocount, 0);
	ofr = ocount / obuf->bpf;
	ocount = ofr * obuf->bpf;

	/*
	 * Partially copy structures into local variables, to avoid
	 * unnecessary indirections; this also allows the compiler to
	 * order local variables more "cache-friendly".
	 */
	inch = ibuf->cmax - ibuf->cmin + 1;
	ipos = p->u.resamp.ipos;
	iblksz = p->u.resamp.iblksz;
	onch = obuf->cmax - obuf->cmin + 1;
	opos = p->u.resamp.opos;
	oblksz = p->u.resamp.oblksz;
	ctxbuf = p->u.resamp.ctx;

	/*
	 * Start conversion.
	 */
	DPRINTFN(4, "resamp_bcopy: ifr=%d ofr=%d\n", ifr, ofr);
	for (;;) {
		if ((int)(ipos - opos) > 0) {
			if (ofr == 0)
				break;
			ctx = ctxbuf;
			for (c = onch; c > 0; c--) {
				*odata = *ctx;
				odata++;
				ctx++;
			}
			opos += iblksz;
			ofr--;
		} else {
			if (ifr == 0)
				break;
			ctx = ctxbuf;
			for (c = inch; c > 0; c--) {
				*ctx = *idata;
				idata++;
				ctx++;
			}
			ipos += oblksz;
			ifr--;
		}
	}
	p->u.resamp.ipos = ipos;
	p->u.resamp.opos = opos;
	DPRINTFN(4, "resamp_bcopy: done, ifr=%d ofr=%d\n", ifr, ofr);

	/*
	 * Update FIFO pointers.
	 */
	icount -= ifr * ibuf->bpf;
	ocount -= ofr * obuf->bpf;
	abuf_rdiscard(ibuf, icount);
	abuf_wcommit(obuf, ocount);
}

int
resamp_in(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);

	DPRINTFN(4, "resamp_in: %s\n", p->name);

	if (!ABUF_WOK(obuf) || !ABUF_ROK(ibuf))
		return 0;
	resamp_bcopy(p, ibuf, obuf);
	if (!abuf_flush(obuf))
		return 0;
	return 1;
}

int
resamp_out(struct aproc *p, struct abuf *obuf)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);

	DPRINTFN(4, "resamp_out: %s\n", p->name);

	if (!abuf_fill(ibuf))
		return 0;
	if (!ABUF_WOK(obuf) || !ABUF_ROK(ibuf))
		return 0;
	resamp_bcopy(p, ibuf, obuf);
	return 1;
}

void
resamp_eof(struct aproc *p, struct abuf *ibuf)
{
	DPRINTFN(4, "resamp_eof: %s\n", p->name);

	aproc_del(p);
}

void
resamp_hup(struct aproc *p, struct abuf *obuf)
{
	DPRINTFN(4, "resamp_hup: %s\n", p->name);

	aproc_del(p);
}

void
resamp_ipos(struct aproc *p, struct abuf *ibuf, int delta)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);	
	long long ipos;
	int ifac, ofac;

	DPRINTFN(3, "resamp_ipos: %d\n", delta);

	ifac = p->u.resamp.iblksz;
	ofac = p->u.resamp.oblksz;
	ipos = p->u.resamp.idelta + (long long)delta * ofac;
	delta = (ipos + ifac - 1) / ifac;
	p->u.resamp.idelta = ipos - (long long)delta * ifac;
	abuf_ipos(obuf, delta);
}

void
resamp_opos(struct aproc *p, struct abuf *obuf, int delta)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);
	long long opos;
	int ifac, ofac;

	DPRINTFN(3, "resamp_opos: %d\n", delta);

	ifac = p->u.resamp.iblksz;
	ofac = p->u.resamp.oblksz;
	opos = p->u.resamp.odelta + (long long)delta * ifac;
	delta = (opos + ofac - 1) / ofac;
	p->u.resamp.odelta = opos - (long long)delta * ofac;
	abuf_opos(ibuf, delta);
}

struct aproc_ops resamp_ops = {
	"resamp",
	resamp_in,
	resamp_out,
	resamp_eof,
	resamp_hup,
	NULL,
	NULL,
	resamp_ipos,
	resamp_opos,
	NULL
};

struct aproc *
resamp_new(char *name, unsigned iblksz, unsigned oblksz)
{
	struct aproc *p;
	unsigned i;

	p = aproc_new(&resamp_ops, name);
	p->u.resamp.iblksz = iblksz;
	p->u.resamp.oblksz = oblksz;
	p->u.resamp.ipos = 0;
	p->u.resamp.opos = 0;
	p->u.resamp.idelta = 0;
	p->u.resamp.odelta = 0;
	for (i = 0; i < NCHAN_MAX; i++)
		p->u.resamp.ctx[i] = 0;
#ifdef DEBUG
	if (debug_level > 0)
		fprintf(stderr, "resamp_new: %u/%u\n", iblksz, oblksz);
#endif
	return p;
}

/*
 * Convert one block.
 */
void
cmap_bcopy(struct aproc *p, struct abuf *ibuf, struct abuf *obuf)
{
	unsigned inch;
	short *idata;
	unsigned onch;
	short *odata;
	short *ctx, *ictx, *octx;
	unsigned c, f, scount, icount, ocount;

	/*
	 * Calculate max frames readable at once from the input buffer.
	 */
	idata = (short *)abuf_rgetblk(ibuf, &icount, 0);
	icount /= ibuf->bpf;
	if (icount == 0)
		return;
	odata = (short *)abuf_wgetblk(obuf, &ocount, 0);
	ocount /= obuf->bpf;
	if (ocount == 0)
		return;
	scount = icount < ocount ? icount : ocount;
	inch = ibuf->cmax - ibuf->cmin + 1;
	onch = obuf->cmax - obuf->cmin + 1;
	ictx = p->u.cmap.ctx + ibuf->cmin;
	octx = p->u.cmap.ctx + obuf->cmin;

	for (f = scount; f > 0; f--) {
		ctx = ictx;
		for (c = inch; c > 0; c--) {
			*ctx = *idata;
			idata++;
			ctx++;
		}
		ctx = octx;
		for (c = onch; c > 0; c--) {
			*odata = *ctx;
			odata++;
			ctx++;
		}
	}
	DPRINTFN(4, "cmap_bcopy: scount = %u\n", scount);
	abuf_rdiscard(ibuf, scount * ibuf->bpf);
	abuf_wcommit(obuf, scount * obuf->bpf);
}

int
cmap_in(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);

	DPRINTFN(4, "cmap_in: %s\n", p->name);

	if (!ABUF_WOK(obuf) || !ABUF_ROK(ibuf))
		return 0;
	cmap_bcopy(p, ibuf, obuf);
	if (!abuf_flush(obuf))
		return 0;
	return 1;
}

int
cmap_out(struct aproc *p, struct abuf *obuf)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);

	DPRINTFN(4, "cmap_out: %s\n", p->name);

	if (!abuf_fill(ibuf))
		return 0;
	if (!ABUF_WOK(obuf) || !ABUF_ROK(ibuf))
		return 0;
	cmap_bcopy(p, ibuf, obuf);
	return 1;
}

void
cmap_eof(struct aproc *p, struct abuf *ibuf)
{
	DPRINTFN(4, "cmap_eof: %s\n", p->name);

	aproc_del(p);
}

void
cmap_hup(struct aproc *p, struct abuf *obuf)
{
	DPRINTFN(4, "cmap_hup: %s\n", p->name);

	aproc_del(p);
}

struct aproc_ops cmap_ops = {
	"cmap",
	cmap_in,
	cmap_out,
	cmap_eof,
	cmap_hup,
	NULL,
	NULL,
	aproc_ipos,
	aproc_opos,
	NULL
};

struct aproc *
cmap_new(char *name, struct aparams *ipar, struct aparams *opar)
{
	struct aproc *p;
	unsigned i;

	p = aproc_new(&cmap_ops, name);
	for (i = 0; i < NCHAN_MAX; i++)
		p->u.cmap.ctx[i] = 0;
#ifdef DEBUG
	if (debug_level > 0) {
		fprintf(stderr, "cmap_new: %s: ", p->name);
		aparams_print2(ipar, opar);
		fprintf(stderr, "\n");
	}
#endif
	return p;
}

/*
 * Convert one block.
 */
void
enc_bcopy(struct aproc *p, struct abuf *ibuf, struct abuf *obuf)
{
	unsigned nch, scount, icount, ocount;
	unsigned f;
	short *idata;
	int s;
	unsigned oshift;
	int osigbit;
	unsigned obps;
	unsigned i;
	unsigned char *odata;
	int obnext;
	int osnext;

	/*
	 * Calculate max frames readable at once from the input buffer.
	 */
	idata = (short *)abuf_rgetblk(ibuf, &icount, 0);
	icount /= ibuf->bpf;
	if (icount == 0)
		return;
	odata = abuf_wgetblk(obuf, &ocount, 0);
	ocount /= obuf->bpf;
	if (ocount == 0)
		return;
	scount = (icount < ocount) ? icount : ocount;
	nch = ibuf->cmax - ibuf->cmin + 1;
	DPRINTFN(4, "enc_bcopy: scount = %u, nch = %u\n", scount, nch);

	/*
	 * Partially copy structures into local variables, to avoid
	 * unnecessary indirections; this also allows the compiler to
	 * order local variables more "cache-friendly".
	 */
	oshift = p->u.conv.shift;
	osigbit = p->u.conv.sigbit;
	obps = p->u.conv.bps;
	obnext = p->u.conv.bnext;
	osnext = p->u.conv.snext;

	/*
	 * Start conversion.
	 */
	odata += p->u.conv.bfirst;
	for (f = scount * nch; f > 0; f--) {
		s = *idata++;
		s <<= 16;
		s >>= oshift;
		s ^= osigbit;
		for (i = obps; i > 0; i--) {
			*odata = (unsigned char)s;
			s >>= 8;
			odata += obnext;
		}
		odata += osnext;
	}

	/*
	 * Update FIFO pointers.
	 */
	abuf_rdiscard(ibuf, scount * ibuf->bpf);
	abuf_wcommit(obuf, scount * obuf->bpf);
}

int
enc_in(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);

	DPRINTFN(4, "enc_in: %s\n", p->name);

	if (!ABUF_WOK(obuf) || !ABUF_ROK(ibuf))
		return 0;
	enc_bcopy(p, ibuf, obuf);
	if (!abuf_flush(obuf))
		return 0;
	return 1;
}

int
enc_out(struct aproc *p, struct abuf *obuf)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);

	DPRINTFN(4, "enc_out: %s\n", p->name);

	if (!abuf_fill(ibuf))
		return 0;
	if (!ABUF_WOK(obuf) || !ABUF_ROK(ibuf))
		return 0;
	enc_bcopy(p, ibuf, obuf);
	return 1;
}

void
enc_eof(struct aproc *p, struct abuf *ibuf)
{
	DPRINTFN(4, "enc_eof: %s\n", p->name);

	aproc_del(p);
}

void
enc_hup(struct aproc *p, struct abuf *obuf)
{
	DPRINTFN(4, "enc_hup: %s\n", p->name);

	aproc_del(p);
}

struct aproc_ops enc_ops = {
	"enc",
	enc_in,
	enc_out,
	enc_eof,
	enc_hup,
	NULL,
	NULL,
	aproc_ipos,
	aproc_opos,
	NULL
};

struct aproc *
enc_new(char *name, struct aparams *par)
{
	struct aproc *p;

	p = aproc_new(&enc_ops, name);
	p->u.conv.bps = par->bps;
	p->u.conv.sigbit = par->sig ? 0 : 1 << (par->bits - 1);
	if (par->msb) {
		p->u.conv.shift = 32 - par->bps * 8;
	} else {
		p->u.conv.shift = 32 - par->bits;
	}
	if (!par->le) {
		p->u.conv.bfirst = par->bps - 1;
		p->u.conv.bnext = -1;
		p->u.conv.snext = 2 * par->bps;
	} else {
		p->u.conv.bfirst = 0;
		p->u.conv.bnext = 1;
		p->u.conv.snext = 0;
	}
#ifdef DEBUG
	if (debug_level > 0) {
		fprintf(stderr, "enc_new: %s: ", p->name);
		aparams_print(par);
		fprintf(stderr, "\n");
	}
#endif
	return p;
}

/*
 * Convert one block.
 */
void
dec_bcopy(struct aproc *p, struct abuf *ibuf, struct abuf *obuf)
{
	unsigned nch, scount, icount, ocount;
	unsigned f;
	unsigned ibps;
	unsigned i;
	int s = 0xdeadbeef;
	unsigned char *idata;
	int ibnext;
	int isnext;
	int isigbit;
	unsigned ishift;
	short *odata;

	/*
	 * Calculate max frames readable at once from the input buffer.
	 */
	idata = abuf_rgetblk(ibuf, &icount, 0);
	icount /= ibuf->bpf;
	if (icount == 0)
		return;
	odata = (short *)abuf_wgetblk(obuf, &ocount, 0);
	ocount /= obuf->bpf;
	if (ocount == 0)
		return;
	scount = (icount < ocount) ? icount : ocount;
	nch = obuf->cmax - obuf->cmin + 1;
	DPRINTFN(4, "dec_bcopy: scount = %u, nch = %u\n", scount, nch);

	/*
	 * Partially copy structures into local variables, to avoid
	 * unnecessary indirections; this also allows the compiler to
	 * order local variables more "cache-friendly".
	 */
	ibps = p->u.conv.bps;
	ibnext = p->u.conv.bnext;
	isigbit = p->u.conv.sigbit;
	ishift = p->u.conv.shift;
	isnext = p->u.conv.snext;

	/*
	 * Start conversion.
	 */
	idata += p->u.conv.bfirst;
	for (f = scount * nch; f > 0; f--) {
		for (i = ibps; i > 0; i--) {
			s <<= 8;
			s |= *idata;
			idata += ibnext;
		}
		idata += isnext;
		s ^= isigbit;
		s <<= ishift;
		s >>= 16;
		*odata++ = s;
	}

	/*
	 * Update FIFO pointers.
	 */
	abuf_rdiscard(ibuf, scount * ibuf->bpf);
	abuf_wcommit(obuf, scount * obuf->bpf);
}

int
dec_in(struct aproc *p, struct abuf *ibuf)
{
	struct abuf *obuf = LIST_FIRST(&p->obuflist);

	DPRINTFN(4, "dec_in: %s\n", p->name);

	if (!ABUF_WOK(obuf) || !ABUF_ROK(ibuf))
		return 0;
	dec_bcopy(p, ibuf, obuf);
	if (!abuf_flush(obuf))
		return 0;
	return 1;
}

int
dec_out(struct aproc *p, struct abuf *obuf)
{
	struct abuf *ibuf = LIST_FIRST(&p->ibuflist);

	DPRINTFN(4, "dec_out: %s\n", p->name);

	if (!abuf_fill(ibuf))
		return 0;
	if (!ABUF_WOK(obuf) || !ABUF_ROK(ibuf))
		return 0;
	dec_bcopy(p, ibuf, obuf);
	return 1;
}

void
dec_eof(struct aproc *p, struct abuf *ibuf)
{
	DPRINTFN(4, "dec_eof: %s\n", p->name);

	aproc_del(p);
}

void
dec_hup(struct aproc *p, struct abuf *obuf)
{
	DPRINTFN(4, "dec_hup: %s\n", p->name);

	aproc_del(p);
}

struct aproc_ops dec_ops = {
	"dec",
	dec_in,
	dec_out,
	dec_eof,
	dec_hup,
	NULL,
	NULL,
	aproc_ipos,
	aproc_opos,
	NULL
};

struct aproc *
dec_new(char *name, struct aparams *par)
{
	struct aproc *p;

	p = aproc_new(&dec_ops, name);
	p->u.conv.bps = par->bps;
	p->u.conv.sigbit = par->sig ? 0 : 1 << (par->bits - 1);
	if (par->msb) {
		p->u.conv.shift = 32 - par->bps * 8;
	} else {
		p->u.conv.shift = 32 - par->bits;
	}
	if (par->le) {
		p->u.conv.bfirst = par->bps - 1;
		p->u.conv.bnext = -1;
		p->u.conv.snext = 2 * par->bps;
	} else {
		p->u.conv.bfirst = 0;
		p->u.conv.bnext = 1;
		p->u.conv.snext = 0;
	}
#ifdef DEBUG
	if (debug_level > 0) {
		fprintf(stderr, "dec_new: %s: ", p->name);		
		aparams_print(par);
		fprintf(stderr, "\n");
	}
#endif
	return p;
}