+/**
+ * \file pcm/pcm_adpcm.c
+ * \ingroup PCM_Plugins
+ * \brief PCM Ima-ADPCM Conversion Plugin Interface
+ * \author Abramo Bagnara <abramo@alsa-project.org>
+ * \author Uros Bizjak <uros@kss-loka.si>
+ * \author Jaroslav Kysela <perex@perex.cz>
+ * \date 2000-2001
+ */
/*
- * PCM - Ima-ADPC conversion
+ * PCM - Ima-ADPCM conversion
* Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
* Copyright (c) 1999 by Uros Bizjak <uros@kss-loka.si>
- * Jaroslav Kysela <perex@suse.cz>
+ * Jaroslav Kysela <perex@perex.cz>
*
* Based on Version 1.2, 18-Dec-92 implementation of Intel/DVI ADPCM code
* by Jack Jansen, CWI, Amsterdam <Jack.Jansen@cwi.nl>, Copyright 1992
* by Stichting Mathematisch Centrum, Amsterdam, The Netherlands.
*
* This library is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Library General Public License as
- * published by the Free Software Foundation; either version 2 of
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU Library General Public License for more details.
+ * GNU Lesser General Public License for more details.
*
- * You should have received a copy of the GNU Library General Public
+ * You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
The algorithm for this coder was taken from:
Proposal for Standardized Audio Interstreamge Formats,
-IMA compatability project proceedings, Vol 2, Issue 2, May 1992.
+IMA compatibility project proceedings, Vol 2, Issue 2, May 1992.
- No, this is *not* a G.721 coder/decoder. The algorithm used by G.721
is very complicated, requiring oodles of floating-point ops per
come across a good description of XA yet.
*/
-#include <byteswap.h>
+#include "bswap.h"
#include "pcm_local.h"
#include "pcm_plugin.h"
-typedef void (*adpcm_f)(const snd_pcm_channel_area_t *src_areas,
- snd_pcm_uframes_t src_offset,
- const snd_pcm_channel_area_t *dst_areas,
+#include "plugin_ops.h"
+
+#ifndef PIC
+/* entry for static linking */
+const char *_snd_module_pcm_adpcm = "";
+#endif
+
+#ifndef DOC_HIDDEN
+
+typedef void (*adpcm_f)(const snd_pcm_channel_area_t *dst_areas,
snd_pcm_uframes_t dst_offset,
- unsigned int channels, snd_pcm_uframes_t frames, int getputidx,
+ const snd_pcm_channel_area_t *src_areas,
+ snd_pcm_uframes_t src_offset,
+ unsigned int channels, snd_pcm_uframes_t frames,
+ unsigned int getputidx,
snd_pcm_adpcm_state_t *states);
typedef struct {
/* This field need to be the first */
snd_pcm_plugin_t plug;
- int getput_idx;
+ unsigned int getput_idx;
adpcm_f func;
- int sformat;
+ snd_pcm_format_t sformat;
snd_pcm_adpcm_state_t *states;
} snd_pcm_adpcm_t;
+#endif
+
/* First table lookup for Ima-ADPCM quantizer */
-static char IndexAdjust[8] = { -1, -1, -1, -1, 2, 4, 6, 8 };
+static const char IndexAdjust[8] = { -1, -1, -1, -1, 2, 4, 6, 8 };
/* Second table lookup for Ima-ADPCM quantizer */
-static short StepSize[89] = {
+static const short StepSize[89] = {
7, 8, 9, 10, 11, 12, 13, 14, 16, 17,
19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
50, 55, 60, 66, 73, 80, 88, 97, 107, 118,
*
* But in shift step bits are dropped. The net result of this is
* that even if you have fast mul/div hardware you cannot put it to
- * good use since the fixup would be too expensive.
+ * good use since the fix-up would be too expensive.
*/
step = StepSize[state->step_idx];
return (state->pred_val);
}
-void snd_pcm_adpcm_decode(const snd_pcm_channel_area_t *src_areas,
- snd_pcm_uframes_t src_offset,
- const snd_pcm_channel_area_t *dst_areas,
+#ifndef DOC_HIDDEN
+
+void snd_pcm_adpcm_decode(const snd_pcm_channel_area_t *dst_areas,
snd_pcm_uframes_t dst_offset,
- unsigned int channels, snd_pcm_uframes_t frames, int putidx,
+ const snd_pcm_channel_area_t *src_areas,
+ snd_pcm_uframes_t src_offset,
+ unsigned int channels, snd_pcm_uframes_t frames,
+ unsigned int putidx,
snd_pcm_adpcm_state_t *states)
{
#define PUT16_LABELS
void *put = put16_labels[putidx];
unsigned int channel;
for (channel = 0; channel < channels; ++channel, ++states) {
- char *src;
+ const char *src;
int srcbit;
char *dst;
int src_step, srcbit_step, dst_step;
snd_pcm_uframes_t frames1;
const snd_pcm_channel_area_t *src_area = &src_areas[channel];
const snd_pcm_channel_area_t *dst_area = &dst_areas[channel];
-#if 0
- if (!src_area->enabled) {
- if (dst_area->wanted)
- snd_pcm_area_silence(dst_area, dst_offset, frames, dst_sfmt);
- dst_area->enabled = 0;
- continue;
- }
- dst_area->enabled = 1;
-#endif
srcbit = src_area->first + src_area->step * src_offset;
- src = src_area->addr + srcbit / 8;
+ src = (const char *) src_area->addr + srcbit / 8;
srcbit %= 8;
src_step = src_area->step / 8;
srcbit_step = src_area->step % 8;
frames1 = frames;
while (frames1-- > 0) {
int16_t sample;
- int v;
+ unsigned char v;
if (srcbit)
v = *src & 0x0f;
else
}
}
-void snd_pcm_adpcm_encode(const snd_pcm_channel_area_t *src_areas,
- snd_pcm_uframes_t src_offset,
- const snd_pcm_channel_area_t *dst_areas,
+void snd_pcm_adpcm_encode(const snd_pcm_channel_area_t *dst_areas,
snd_pcm_uframes_t dst_offset,
- unsigned int channels, snd_pcm_uframes_t frames, int getidx,
+ const snd_pcm_channel_area_t *src_areas,
+ snd_pcm_uframes_t src_offset,
+ unsigned int channels, snd_pcm_uframes_t frames,
+ unsigned int getidx,
snd_pcm_adpcm_state_t *states)
{
#define GET16_LABELS
unsigned int channel;
int16_t sample = 0;
for (channel = 0; channel < channels; ++channel, ++states) {
- char *src;
+ const char *src;
char *dst;
int dstbit;
int src_step, dst_step, dstbit_step;
snd_pcm_uframes_t frames1;
const snd_pcm_channel_area_t *src_area = &src_areas[channel];
const snd_pcm_channel_area_t *dst_area = &dst_areas[channel];
-#if 0
- if (!src_area->enabled) {
- if (dst_area->wanted)
- snd_pcm_area_silence(dst_area, dst_offset, frames, dst_sfmt);
- dst_area->enabled = 0;
- continue;
- }
- dst_area->enabled = 1;
-#endif
src = snd_pcm_channel_area_addr(src_area, src_offset);
src_step = snd_pcm_channel_area_step(src_area);
dstbit = dst_area->first + dst_area->step * dst_offset;
- dst = dst_area->addr + dstbit / 8;
+ dst = (char *) dst_area->addr + dstbit / 8;
dstbit %= 8;
dst_step = dst_area->step / 8;
dstbit_step = dst_area->step % 8;
}
}
+#endif
+
static int snd_pcm_adpcm_hw_refine_cprepare(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
{
- snd_pcm_adpcm_t *adpcm = pcm->private;
+ snd_pcm_adpcm_t *adpcm = pcm->private_data;
int err;
- snd_mask_t *access_mask = alloca(snd_mask_sizeof());
- snd_mask_load(access_mask, SND_PCM_ACCBIT_PLUGIN);
- err = _snd_pcm_hw_param_mask(params, SND_PCM_HW_PARAM_ACCESS,
- access_mask);
+ snd_pcm_access_mask_t access_mask = { SND_PCM_ACCBIT_SHM };
+ err = _snd_pcm_hw_param_set_mask(params, SND_PCM_HW_PARAM_ACCESS,
+ &access_mask);
if (err < 0)
return err;
if (adpcm->sformat == SND_PCM_FORMAT_IMA_ADPCM) {
- snd_mask_t *format_mask = alloca(snd_mask_sizeof());
- snd_mask_load(format_mask, SND_PCM_FMTBIT_LINEAR);
- err = _snd_pcm_hw_param_mask(params, SND_PCM_HW_PARAM_FORMAT,
- format_mask);
+ snd_pcm_format_mask_t format_mask = { SND_PCM_FMTBIT_LINEAR };
+ err = _snd_pcm_hw_param_set_mask(params, SND_PCM_HW_PARAM_FORMAT,
+ &format_mask);
} else {
- err = _snd_pcm_hw_param_set(params,
- SND_PCM_HW_PARAM_FORMAT,
- SND_PCM_FORMAT_IMA_ADPCM, 0);
+ err = _snd_pcm_hw_params_set_format(params,
+ SND_PCM_FORMAT_IMA_ADPCM);
}
if (err < 0)
return err;
- err = _snd_pcm_hw_param_set(params, SND_PCM_HW_PARAM_SUBFORMAT,
- SND_PCM_SUBFORMAT_STD, 0);
+ err = _snd_pcm_hw_params_set_subformat(params,
+ SND_PCM_SUBFORMAT_STD);
if (err < 0)
return err;
params->info &= ~(SND_PCM_INFO_MMAP | SND_PCM_INFO_MMAP_VALID);
static int snd_pcm_adpcm_hw_refine_sprepare(snd_pcm_t *pcm, snd_pcm_hw_params_t *sparams)
{
- snd_pcm_adpcm_t *adpcm = pcm->private;
- snd_mask_t *saccess_mask = alloca(snd_mask_sizeof());
- snd_mask_load(saccess_mask, SND_PCM_ACCBIT_MMAP);
+ snd_pcm_adpcm_t *adpcm = pcm->private_data;
+ snd_pcm_access_mask_t saccess_mask = { SND_PCM_ACCBIT_MMAP };
_snd_pcm_hw_params_any(sparams);
- _snd_pcm_hw_param_mask(sparams, SND_PCM_HW_PARAM_ACCESS,
- saccess_mask);
- _snd_pcm_hw_param_set(sparams, SND_PCM_HW_PARAM_FORMAT,
- adpcm->sformat, 0);
- _snd_pcm_hw_param_set(sparams, SND_PCM_HW_PARAM_SUBFORMAT,
- SND_PCM_SUBFORMAT_STD, 0);
+ _snd_pcm_hw_param_set_mask(sparams, SND_PCM_HW_PARAM_ACCESS,
+ &saccess_mask);
+ _snd_pcm_hw_params_set_format(sparams, adpcm->sformat);
+ _snd_pcm_hw_params_set_subformat(sparams, SND_PCM_SUBFORMAT_STD);
return 0;
}
snd_pcm_adpcm_hw_refine_cchange,
snd_pcm_adpcm_hw_refine_sprepare,
snd_pcm_adpcm_hw_refine_schange,
- snd_pcm_plugin_hw_refine_slave);
+ snd_pcm_generic_hw_refine);
}
static int snd_pcm_adpcm_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t * params)
{
- snd_pcm_adpcm_t *adpcm = pcm->private;
+ snd_pcm_adpcm_t *adpcm = pcm->private_data;
+ snd_pcm_format_t format;
int err = snd_pcm_hw_params_slave(pcm, params,
snd_pcm_adpcm_hw_refine_cchange,
snd_pcm_adpcm_hw_refine_sprepare,
snd_pcm_adpcm_hw_refine_schange,
- snd_pcm_plugin_hw_params_slave);
+ snd_pcm_generic_hw_params);
if (err < 0)
return err;
+ err = INTERNAL(snd_pcm_hw_params_get_format)(params, &format);
+ if (err < 0)
+ return err;
if (pcm->stream == SND_PCM_STREAM_PLAYBACK) {
if (adpcm->sformat == SND_PCM_FORMAT_IMA_ADPCM) {
- adpcm->getput_idx = snd_pcm_linear_get_index(snd_pcm_hw_param_value(params, SND_PCM_HW_PARAM_FORMAT, 0), SND_PCM_FORMAT_S16);
+ adpcm->getput_idx = snd_pcm_linear_get_index(format, SND_PCM_FORMAT_S16);
adpcm->func = snd_pcm_adpcm_encode;
} else {
adpcm->getput_idx = snd_pcm_linear_put_index(SND_PCM_FORMAT_S16, adpcm->sformat);
}
} else {
if (adpcm->sformat == SND_PCM_FORMAT_IMA_ADPCM) {
- adpcm->getput_idx = snd_pcm_linear_put_index(SND_PCM_FORMAT_S16, snd_pcm_hw_param_value(params, SND_PCM_HW_PARAM_FORMAT, 0));
+ adpcm->getput_idx = snd_pcm_linear_put_index(SND_PCM_FORMAT_S16, format);
adpcm->func = snd_pcm_adpcm_decode;
} else {
adpcm->getput_idx = snd_pcm_linear_get_index(adpcm->sformat, SND_PCM_FORMAT_S16);
}
}
assert(!adpcm->states);
- adpcm->states = malloc(snd_pcm_hw_param_value(params, SND_PCM_HW_PARAM_CHANNELS, 0) * sizeof(*adpcm->states));
+ adpcm->states = malloc(adpcm->plug.gen.slave->channels * sizeof(*adpcm->states));
+ if (adpcm->states == NULL)
+ return -ENOMEM;
return 0;
}
static int snd_pcm_adpcm_hw_free(snd_pcm_t *pcm)
{
- snd_pcm_adpcm_t *adpcm = pcm->private;
- if (adpcm->states) {
- free(adpcm->states);
- adpcm->states = 0;
- }
- return snd_pcm_hw_free(adpcm->plug.slave);
+ snd_pcm_adpcm_t *adpcm = pcm->private_data;
+ free(adpcm->states);
+ adpcm->states = NULL;
+ return snd_pcm_hw_free(adpcm->plug.gen.slave);
}
static int snd_pcm_adpcm_init(snd_pcm_t *pcm)
{
- snd_pcm_adpcm_t *adpcm = pcm->private;
+ snd_pcm_adpcm_t *adpcm = pcm->private_data;
unsigned int k;
for (k = 0; k < pcm->channels; ++k) {
adpcm->states[k].pred_val = 0;
return 0;
}
-static snd_pcm_sframes_t snd_pcm_adpcm_write_areas(snd_pcm_t *pcm,
- const snd_pcm_channel_area_t *areas,
- snd_pcm_uframes_t offset,
- snd_pcm_uframes_t size,
- snd_pcm_uframes_t *slave_sizep)
+static snd_pcm_uframes_t
+snd_pcm_adpcm_write_areas(snd_pcm_t *pcm,
+ const snd_pcm_channel_area_t *areas,
+ snd_pcm_uframes_t offset,
+ snd_pcm_uframes_t size,
+ const snd_pcm_channel_area_t *slave_areas,
+ snd_pcm_uframes_t slave_offset,
+ snd_pcm_uframes_t *slave_sizep)
{
- snd_pcm_adpcm_t *adpcm = pcm->private;
- snd_pcm_t *slave = adpcm->plug.slave;
- snd_pcm_uframes_t xfer = 0;
- snd_pcm_sframes_t err = 0;
- if (slave_sizep && *slave_sizep < size)
+ snd_pcm_adpcm_t *adpcm = pcm->private_data;
+ if (size > *slave_sizep)
size = *slave_sizep;
- assert(size > 0);
- while (xfer < size) {
- snd_pcm_uframes_t frames = snd_pcm_mmap_playback_xfer(slave, size - xfer);
- adpcm->func(areas, offset,
- snd_pcm_mmap_areas(slave), snd_pcm_mmap_offset(slave),
- pcm->channels, frames,
- adpcm->getput_idx, adpcm->states);
- err = snd_pcm_mmap_forward(slave, frames);
- if (err < 0)
- break;
- assert((snd_pcm_uframes_t)err == frames);
- offset += err;
- xfer += err;
- snd_pcm_mmap_hw_forward(pcm, err);
- }
- if (xfer > 0) {
- if (slave_sizep)
- *slave_sizep = xfer;
- return xfer;
- }
- return err;
+ adpcm->func(slave_areas, slave_offset,
+ areas, offset,
+ pcm->channels, size,
+ adpcm->getput_idx, adpcm->states);
+ *slave_sizep = size;
+ return size;
}
-static snd_pcm_sframes_t snd_pcm_adpcm_read_areas(snd_pcm_t *pcm,
- const snd_pcm_channel_area_t *areas,
- snd_pcm_uframes_t offset,
- snd_pcm_uframes_t size,
- snd_pcm_uframes_t *slave_sizep)
+static snd_pcm_uframes_t
+snd_pcm_adpcm_read_areas(snd_pcm_t *pcm,
+ const snd_pcm_channel_area_t *areas,
+ snd_pcm_uframes_t offset,
+ snd_pcm_uframes_t size,
+ const snd_pcm_channel_area_t *slave_areas,
+ snd_pcm_uframes_t slave_offset,
+ snd_pcm_uframes_t *slave_sizep)
{
- snd_pcm_adpcm_t *adpcm = pcm->private;
- snd_pcm_t *slave = adpcm->plug.slave;
- snd_pcm_uframes_t xfer = 0;
- snd_pcm_sframes_t err = 0;
- if (slave_sizep && *slave_sizep < size)
+ snd_pcm_adpcm_t *adpcm = pcm->private_data;
+ if (size > *slave_sizep)
size = *slave_sizep;
- assert(size > 0);
- while (xfer < size) {
- snd_pcm_uframes_t frames = snd_pcm_mmap_capture_xfer(slave, size - xfer);
- adpcm->func(snd_pcm_mmap_areas(slave), snd_pcm_mmap_offset(slave),
- areas, offset,
- pcm->channels, frames,
- adpcm->getput_idx, adpcm->states);
- err = snd_pcm_mmap_forward(slave, frames);
- if (err < 0)
- break;
- assert((snd_pcm_uframes_t)err == frames);
- offset += err;
- xfer += err;
- snd_pcm_mmap_hw_forward(pcm, err);
- }
- if (xfer > 0) {
- if (slave_sizep)
- *slave_sizep = xfer;
- return xfer;
- }
- return err;
+ adpcm->func(areas, offset,
+ slave_areas, slave_offset,
+ pcm->channels, size,
+ adpcm->getput_idx, adpcm->states);
+ *slave_sizep = size;
+ return size;
}
static void snd_pcm_adpcm_dump(snd_pcm_t *pcm, snd_output_t *out)
{
- snd_pcm_adpcm_t *adpcm = pcm->private;
+ snd_pcm_adpcm_t *adpcm = pcm->private_data;
snd_output_printf(out, "Ima-ADPCM conversion PCM (%s)\n",
snd_pcm_format_name(adpcm->sformat));
if (pcm->setup) {
snd_pcm_dump_setup(pcm, out);
}
snd_output_printf(out, "Slave: ");
- snd_pcm_dump(adpcm->plug.slave, out);
+ snd_pcm_dump(adpcm->plug.gen.slave, out);
}
-snd_pcm_ops_t snd_pcm_adpcm_ops = {
- close: snd_pcm_plugin_close,
- card: snd_pcm_plugin_card,
- info: snd_pcm_plugin_info,
- hw_refine: snd_pcm_adpcm_hw_refine,
- hw_params: snd_pcm_adpcm_hw_params,
- hw_free: snd_pcm_adpcm_hw_free,
- sw_params: snd_pcm_plugin_sw_params,
- channel_info: snd_pcm_plugin_channel_info,
- dump: snd_pcm_adpcm_dump,
- nonblock: snd_pcm_plugin_nonblock,
- async: snd_pcm_plugin_async,
- mmap: snd_pcm_plugin_mmap,
- munmap: snd_pcm_plugin_munmap,
+static const snd_pcm_ops_t snd_pcm_adpcm_ops = {
+ .close = snd_pcm_generic_close,
+ .info = snd_pcm_generic_info,
+ .hw_refine = snd_pcm_adpcm_hw_refine,
+ .hw_params = snd_pcm_adpcm_hw_params,
+ .hw_free = snd_pcm_adpcm_hw_free,
+ .sw_params = snd_pcm_generic_sw_params,
+ .channel_info = snd_pcm_generic_channel_info,
+ .dump = snd_pcm_adpcm_dump,
+ .nonblock = snd_pcm_generic_nonblock,
+ .async = snd_pcm_generic_async,
+ .mmap = snd_pcm_generic_mmap,
+ .munmap = snd_pcm_generic_munmap,
+ .query_chmaps = snd_pcm_generic_query_chmaps,
+ .get_chmap = snd_pcm_generic_get_chmap,
+ .set_chmap = snd_pcm_generic_set_chmap,
};
-int snd_pcm_adpcm_open(snd_pcm_t **pcmp, char *name, int sformat, snd_pcm_t *slave, int close_slave)
+/**
+ * \brief Creates a new Ima-ADPCM conversion PCM
+ * \param pcmp Returns created PCM handle
+ * \param name Name of PCM
+ * \param sformat Slave (destination) format
+ * \param slave Slave PCM handle
+ * \param close_slave When set, the slave PCM handle is closed with copy PCM
+ * \retval zero on success otherwise a negative error code
+ * \warning Using of this function might be dangerous in the sense
+ * of compatibility reasons. The prototype might be freely
+ * changed in future.
+ */
+int snd_pcm_adpcm_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, snd_pcm_t *slave, int close_slave)
{
snd_pcm_t *pcm;
snd_pcm_adpcm_t *adpcm;
+ int err;
assert(pcmp && slave);
if (snd_pcm_format_linear(sformat) != 1 &&
sformat != SND_PCM_FORMAT_IMA_ADPCM)
return -ENOMEM;
}
adpcm->sformat = sformat;
+ snd_pcm_plugin_init(&adpcm->plug);
adpcm->plug.read = snd_pcm_adpcm_read_areas;
adpcm->plug.write = snd_pcm_adpcm_write_areas;
adpcm->plug.init = snd_pcm_adpcm_init;
- adpcm->plug.slave = slave;
- adpcm->plug.close_slave = close_slave;
+ adpcm->plug.gen.slave = slave;
+ adpcm->plug.gen.close_slave = close_slave;
- pcm = calloc(1, sizeof(snd_pcm_t));
- if (!pcm) {
+ err = snd_pcm_new(&pcm, SND_PCM_TYPE_ADPCM, name, slave->stream, slave->mode);
+ if (err < 0) {
free(adpcm);
- return -ENOMEM;
+ return err;
}
- if (name)
- pcm->name = strdup(name);
- pcm->type = SND_PCM_TYPE_ADPCM;
- pcm->stream = slave->stream;
- pcm->mode = slave->mode;
pcm->ops = &snd_pcm_adpcm_ops;
- pcm->op_arg = pcm;
pcm->fast_ops = &snd_pcm_plugin_fast_ops;
- pcm->fast_op_arg = pcm;
- pcm->private = adpcm;
+ pcm->private_data = adpcm;
pcm->poll_fd = slave->poll_fd;
- pcm->hw_ptr = &adpcm->plug.hw_ptr;
- pcm->appl_ptr = &adpcm->plug.appl_ptr;
+ pcm->poll_events = slave->poll_events;
+ pcm->tstamp_type = slave->tstamp_type;
+ snd_pcm_set_hw_ptr(pcm, &adpcm->plug.hw_ptr, -1, 0);
+ snd_pcm_set_appl_ptr(pcm, &adpcm->plug.appl_ptr, -1, 0);
*pcmp = pcm;
return 0;
}
-int _snd_pcm_adpcm_open(snd_pcm_t **pcmp, char *name,
- snd_config_t *conf,
- int stream, int mode)
+/*! \page pcm_plugins
+
+\section pcm_plugins_adpcm Plugin: Ima-ADPCM
+
+This plugin converts Ima-ADPCM samples to linear or linear to Ima-ADPCM samples
+from master Ima-ADPCM conversion PCM to given slave PCM. The channel count,
+format and rate must match for both of them.
+
+\code
+pcm.name {
+ type adpcm # Ima-ADPCM conversion PCM
+ slave STR # Slave name
+ # or
+ slave { # Slave definition
+ pcm STR # Slave PCM name
+ # or
+ pcm { } # Slave PCM definition
+ format STR # Slave format
+ }
+}
+\endcode
+
+\subsection pcm_plugins_adpcm_funcref Function reference
+
+<UL>
+ <LI>snd_pcm_adpcm_open()
+ <LI>_snd_pcm_adpcm_open()
+</UL>
+
+*/
+
+/**
+ * \brief Creates a new Ima-ADPCM conversion PCM
+ * \param pcmp Returns created PCM handle
+ * \param name Name of PCM
+ * \param root Root configuration node
+ * \param conf Configuration node with copy PCM description
+ * \param stream Stream type
+ * \param mode Stream mode
+ * \retval zero on success otherwise a negative error code
+ * \warning Using of this function might be dangerous in the sense
+ * of compatibility reasons. The prototype might be freely
+ * changed in future.
+ */
+int _snd_pcm_adpcm_open(snd_pcm_t **pcmp, const char *name,
+ snd_config_t *root, snd_config_t *conf,
+ snd_pcm_stream_t stream, int mode)
{
- snd_config_iterator_t i;
- char *sname = NULL;
+ snd_config_iterator_t i, next;
int err;
snd_pcm_t *spcm;
- int sformat = -1;
- snd_config_foreach(i, conf) {
- snd_config_t *n = snd_config_entry(i);
- if (strcmp(n->id, "comment") == 0)
- continue;
- if (strcmp(n->id, "type") == 0)
+ snd_config_t *slave = NULL, *sconf;
+ snd_pcm_format_t sformat;
+ snd_config_for_each(i, next, conf) {
+ snd_config_t *n = snd_config_iterator_entry(i);
+ const char *id;
+ if (snd_config_get_id(n, &id) < 0)
continue;
- if (strcmp(n->id, "stream") == 0)
+ if (snd_pcm_conf_generic_id(id))
continue;
- if (strcmp(n->id, "sname") == 0) {
- err = snd_config_string_get(n, &sname);
- if (err < 0) {
- ERR("Invalid type for %s", n->id);
- return -EINVAL;
- }
+ if (strcmp(id, "slave") == 0) {
+ slave = n;
continue;
}
- if (strcmp(n->id, "sformat") == 0) {
- char *f;
- err = snd_config_string_get(n, &f);
- if (err < 0) {
- ERR("Invalid type for %s", n->id);
- return -EINVAL;
- }
- sformat = snd_pcm_format_value(f);
- if (sformat < 0) {
- ERR("Unknown sformat");
- return -EINVAL;
- }
- if (snd_pcm_format_linear(sformat) != 1 &&
- sformat != SND_PCM_FORMAT_IMA_ADPCM) {
- ERR("Invalid sformat");
- return -EINVAL;
- }
- continue;
- }
- ERR("Unknown field %s", n->id);
+ SNDERR("Unknown field %s", id);
return -EINVAL;
}
- if (!sname) {
- ERR("sname is not defined");
+ if (!slave) {
+ SNDERR("slave is not defined");
return -EINVAL;
}
- if (sformat < 0) {
- ERR("sformat is not defined");
+ err = snd_pcm_slave_conf(root, slave, &sconf, 1,
+ SND_PCM_HW_PARAM_FORMAT, SCONF_MANDATORY, &sformat);
+ if (err < 0)
+ return err;
+ if (snd_pcm_format_linear(sformat) != 1 &&
+ sformat != SND_PCM_FORMAT_IMA_ADPCM) {
+ snd_config_delete(sconf);
+ SNDERR("invalid slave format");
return -EINVAL;
}
- /* This is needed cause snd_config_update may destroy config */
- sname = strdup(sname);
- if (!sname)
- return -ENOMEM;
- err = snd_pcm_open(&spcm, sname, stream, mode);
- free(sname);
+ err = snd_pcm_open_slave(&spcm, root, sconf, stream, mode, conf);
+ snd_config_delete(sconf);
if (err < 0)
return err;
err = snd_pcm_adpcm_open(pcmp, name, sformat, spcm, 1);
snd_pcm_close(spcm);
return err;
}
-
-
+#ifndef DOC_HIDDEN
+SND_DLSYM_BUILD_VERSION(_snd_pcm_adpcm_open, SND_PCM_DLSYM_VERSION);
+#endif