linux/sound/core/oss/rate.c

/*
 *  Rate conversion Plug-In
 *  Copyright (c) 1999 by Jaroslav Kysela <[email protected]>
 *
 *
 *   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
 *   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.
 *
 *   You should have received a copy of the GNU Library General Public
 *   License along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */
  
#include <linux/time.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include "pcm_plugin.h"

#define SHIFT …
#define BITS …
#define R_MASK …

/*
 *  Basic rate conversion plugin
 */

struct rate_channel { … };
 
rate_f;

struct rate_priv { … };

static void rate_init(struct snd_pcm_plugin *plugin)
{ … }

static void resample_expand(struct snd_pcm_plugin *plugin,
			    const struct snd_pcm_plugin_channel *src_channels,
			    struct snd_pcm_plugin_channel *dst_channels,
			    int src_frames, int dst_frames)
{ … }

static void resample_shrink(struct snd_pcm_plugin *plugin,
			    const struct snd_pcm_plugin_channel *src_channels,
			    struct snd_pcm_plugin_channel *dst_channels,
			    int src_frames, int dst_frames)
{ … }

static snd_pcm_sframes_t rate_src_frames(struct snd_pcm_plugin *plugin, snd_pcm_uframes_t frames)
{ … }

static snd_pcm_sframes_t rate_dst_frames(struct snd_pcm_plugin *plugin, snd_pcm_uframes_t frames)
{ … }

static snd_pcm_sframes_t rate_transfer(struct snd_pcm_plugin *plugin,
			     const struct snd_pcm_plugin_channel *src_channels,
			     struct snd_pcm_plugin_channel *dst_channels,
			     snd_pcm_uframes_t frames)
{ … }

static int rate_action(struct snd_pcm_plugin *plugin,
		       enum snd_pcm_plugin_action action,
		       unsigned long udata)
{ … }

int snd_pcm_plugin_build_rate(struct snd_pcm_substream *plug,
			      struct snd_pcm_plugin_format *src_format,
			      struct snd_pcm_plugin_format *dst_format,
			      struct snd_pcm_plugin **r_plugin)
{ … }