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Added initial comments for PCM plugins

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This commit is contained in:
Jaroslav Kysela 2002-01-16 16:42:40 +00:00
parent 6ead410b11
commit a24b602f28
11 changed files with 796 additions and 28 deletions
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78
src/pcm/pcm_adpcm.c
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@ -1,5 +1,14 @@
/**
* \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@suse.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>
@ -56,6 +65,8 @@ IMA compatability project proceedings, Vol 2, Issue 2, May 1992.
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,
const snd_pcm_channel_area_t *src_areas,
@ -73,6 +84,8 @@ typedef struct {
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 };
@ -196,6 +209,8 @@ static int adpcm_decoder(unsigned char code, snd_pcm_adpcm_state_t * state)
return (state->pred_val);
}
#ifndef DOC_HIDDEN
void snd_pcm_adpcm_decode(const snd_pcm_channel_area_t *dst_areas,
snd_pcm_uframes_t dst_offset,
const snd_pcm_channel_area_t *src_areas,
@ -302,6 +317,8 @@ void snd_pcm_adpcm_encode(const snd_pcm_channel_area_t *dst_areas,
}
}
#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_data;
@ -495,7 +512,7 @@ static void snd_pcm_adpcm_dump(snd_pcm_t *pcm, snd_output_t *out)
snd_pcm_dump(adpcm->plug.slave, out);
}
snd_pcm_ops_t snd_pcm_adpcm_ops = {
static snd_pcm_ops_t snd_pcm_adpcm_ops = {
close: snd_pcm_plugin_close,
info: snd_pcm_plugin_info,
hw_refine: snd_pcm_adpcm_hw_refine,
@ -510,6 +527,18 @@ snd_pcm_ops_t snd_pcm_adpcm_ops = {
munmap: snd_pcm_plugin_munmap,
};
/**
* \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;
@ -546,6 +575,49 @@ int snd_pcm_adpcm_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sfor
return 0;
}
/*! \page pcm_plugins
\section pcm_plugins_adpcm Plugin: Ima-ADPCM
This plugin converts Ima-ADPCM samples to linear or linear to Mu-Law 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
}
}
\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)
@ -592,4 +664,6 @@ int _snd_pcm_adpcm_open(snd_pcm_t **pcmp, const char *name,
snd_pcm_close(spcm);
return err;
}
#ifndef DOC_HIDDEN
SND_DLSYM_BUILD_VERSION(_snd_pcm_adpcm_open, SND_PCM_DLSYM_VERSION);
#endif