mirror of https://github.com/asterisk/asterisk
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
129 lines
2.9 KiB
129 lines
2.9 KiB
/*
|
|
* Asterisk -- An open source telephony toolkit.
|
|
*
|
|
* Copyright (C) 1999 - 2005, Digium, Inc.
|
|
*
|
|
* Mark Spencer <markster@digium.com>
|
|
*
|
|
* See http://www.asterisk.org for more information about
|
|
* the Asterisk project. Please do not directly contact
|
|
* any of the maintainers of this project for assistance;
|
|
* the project provides a web site, mailing lists and IRC
|
|
* channels for your use.
|
|
*
|
|
* This program is free software, distributed under the terms of
|
|
* the GNU General Public License Version 2. See the LICENSE file
|
|
* at the top of the source tree.
|
|
*/
|
|
|
|
/*! \file
|
|
*
|
|
* \brief codec_a_mu.c - translate between alaw and ulaw directly
|
|
*
|
|
* \ingroup codecs
|
|
*/
|
|
|
|
#include "asterisk.h"
|
|
|
|
ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
|
|
|
|
#include "asterisk/module.h"
|
|
#include "asterisk/translate.h"
|
|
#include "asterisk/alaw.h"
|
|
#include "asterisk/ulaw.h"
|
|
#include "asterisk/utils.h"
|
|
|
|
#define BUFFER_SAMPLES 8000 /* size for the translation buffers */
|
|
|
|
static unsigned char mu2a[256];
|
|
static unsigned char a2mu[256];
|
|
|
|
/* Sample frame data */
|
|
#include "ex_ulaw.h"
|
|
#include "ex_alaw.h"
|
|
|
|
/*! \brief convert frame data and store into the buffer */
|
|
static int alawtoulaw_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
|
|
{
|
|
int x = f->samples;
|
|
unsigned char *src = f->data.ptr;
|
|
unsigned char *dst = pvt->outbuf.uc + pvt->samples;
|
|
|
|
pvt->samples += x;
|
|
pvt->datalen += x;
|
|
|
|
while (x--)
|
|
*dst++ = a2mu[*src++];
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief convert frame data and store into the buffer */
|
|
static int ulawtoalaw_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
|
|
{
|
|
int x = f->samples;
|
|
unsigned char *src = f->data.ptr;
|
|
unsigned char *dst = pvt->outbuf.uc + pvt->samples;
|
|
|
|
pvt->samples += x;
|
|
pvt->datalen += x;
|
|
|
|
while (x--)
|
|
*dst++ = mu2a[*src++];
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct ast_translator alawtoulaw = {
|
|
.name = "alawtoulaw",
|
|
.srcfmt = AST_FORMAT_ALAW,
|
|
.dstfmt = AST_FORMAT_ULAW,
|
|
.framein = alawtoulaw_framein,
|
|
.sample = alaw_sample,
|
|
.buffer_samples = BUFFER_SAMPLES,
|
|
.buf_size = BUFFER_SAMPLES,
|
|
};
|
|
|
|
static struct ast_translator ulawtoalaw = {
|
|
.name = "ulawtoalaw",
|
|
.srcfmt = AST_FORMAT_ULAW,
|
|
.dstfmt = AST_FORMAT_ALAW,
|
|
.framein = ulawtoalaw_framein,
|
|
.sample = ulaw_sample,
|
|
.buffer_samples = BUFFER_SAMPLES,
|
|
.buf_size = BUFFER_SAMPLES,
|
|
};
|
|
|
|
/*! \brief standard module glue */
|
|
|
|
static int unload_module(void)
|
|
{
|
|
int res;
|
|
|
|
res = ast_unregister_translator(&ulawtoalaw);
|
|
res |= ast_unregister_translator(&alawtoulaw);
|
|
|
|
return res;
|
|
}
|
|
|
|
static int load_module(void)
|
|
{
|
|
int res;
|
|
int x;
|
|
|
|
for (x=0;x<256;x++) {
|
|
mu2a[x] = AST_LIN2A(AST_MULAW(x));
|
|
a2mu[x] = AST_LIN2MU(AST_ALAW(x));
|
|
}
|
|
res = ast_register_translator(&alawtoulaw);
|
|
if (!res)
|
|
res = ast_register_translator(&ulawtoalaw);
|
|
else
|
|
ast_unregister_translator(&alawtoulaw);
|
|
if (res)
|
|
return AST_MODULE_LOAD_FAILURE;
|
|
return AST_MODULE_LOAD_SUCCESS;
|
|
}
|
|
|
|
AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "A-law and Mulaw direct Coder/Decoder");
|