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.
		
		
		
		
		
			
		
			
				
					
					
						
							146 lines
						
					
					
						
							3.1 KiB
						
					
					
				
			
		
		
	
	
							146 lines
						
					
					
						
							3.1 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_alaw.c - translate between signed linear and alaw
 | |
|  * 
 | |
|  * \ingroup codecs
 | |
|  */
 | |
| 
 | |
| /*** MODULEINFO
 | |
| 	<support_level>core</support_level>
 | |
|  ***/
 | |
| 
 | |
| #include "asterisk.h"
 | |
| 
 | |
| ASTERISK_REGISTER_FILE()
 | |
| 
 | |
| #include "asterisk/module.h"
 | |
| #include "asterisk/config.h"
 | |
| #include "asterisk/translate.h"
 | |
| #include "asterisk/alaw.h"
 | |
| #include "asterisk/utils.h"
 | |
| 
 | |
| #define BUFFER_SAMPLES   8096	/* size for the translation buffers */
 | |
| 
 | |
| /* Sample frame data */
 | |
| #include "asterisk/slin.h"
 | |
| #include "ex_alaw.h"
 | |
| 
 | |
| /*! \brief decode frame into lin and fill output buffer. */
 | |
| static int alawtolin_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
 | |
| {
 | |
| 	int i = f->samples;
 | |
| 	unsigned char *src = f->data.ptr;
 | |
| 	int16_t *dst = pvt->outbuf.i16 + pvt->samples;
 | |
| 
 | |
| 	pvt->samples += i;
 | |
| 	pvt->datalen += i * 2;	/* 2 bytes/sample */
 | |
| 	
 | |
| 	while (i--)
 | |
| 		*dst++ = AST_ALAW(*src++);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*! \brief convert and store input samples in output buffer */
 | |
| static int lintoalaw_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
 | |
| {
 | |
| 	int i = f->samples;
 | |
| 	char *dst = pvt->outbuf.c + pvt->samples;
 | |
| 	int16_t *src = f->data.ptr;
 | |
| 
 | |
| 	pvt->samples += i;
 | |
| 	pvt->datalen += i;	/* 1 byte/sample */
 | |
| 
 | |
| 	while (i--) 
 | |
| 		*dst++ = AST_LIN2A(*src++);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static struct ast_translator alawtolin = {
 | |
| 	.name = "alawtolin",
 | |
| 	.src_codec = {
 | |
| 		.name = "alaw",
 | |
| 		.type = AST_MEDIA_TYPE_AUDIO,
 | |
| 		.sample_rate = 8000,
 | |
| 	},
 | |
| 	.dst_codec = {
 | |
| 		.name = "slin",
 | |
| 		.type = AST_MEDIA_TYPE_AUDIO,
 | |
| 		.sample_rate = 8000,
 | |
| 	},
 | |
| 	.format = "slin",
 | |
| 	.framein = alawtolin_framein,
 | |
| 	.sample = alaw_sample,
 | |
| 	.buffer_samples = BUFFER_SAMPLES,
 | |
| 	.buf_size = BUFFER_SAMPLES * 2,
 | |
| };
 | |
| 
 | |
| static struct ast_translator lintoalaw = {
 | |
| 	.name = "lintoalaw",
 | |
| 	.src_codec = {
 | |
| 		.name = "slin",
 | |
| 		.type = AST_MEDIA_TYPE_AUDIO,
 | |
| 		.sample_rate = 8000,
 | |
| 	},
 | |
| 	.dst_codec = {
 | |
| 		.name = "alaw",
 | |
| 		.type = AST_MEDIA_TYPE_AUDIO,
 | |
| 		.sample_rate = 8000,
 | |
| 	},
 | |
| 	.format = "alaw",
 | |
| 	.framein = lintoalaw_framein,
 | |
| 	.sample = slin8_sample,
 | |
| 	.buffer_samples = BUFFER_SAMPLES,
 | |
| 	.buf_size = BUFFER_SAMPLES,
 | |
| };
 | |
| 
 | |
| static int unload_module(void)
 | |
| {
 | |
| 	int res;
 | |
| 
 | |
| 	res = ast_unregister_translator(&lintoalaw);
 | |
| 	res |= ast_unregister_translator(&alawtolin);
 | |
| 
 | |
| 	return res;
 | |
| }
 | |
| 
 | |
| static int load_module(void)
 | |
| {
 | |
| 	int res;
 | |
| 
 | |
| 	res = ast_register_translator(&alawtolin);
 | |
| 	res |= ast_register_translator(&lintoalaw);
 | |
| 
 | |
| 	if (res) {
 | |
| 		unload_module();
 | |
| 		return AST_MODULE_LOAD_FAILURE;
 | |
| 	}
 | |
| 
 | |
| 	return AST_MODULE_LOAD_SUCCESS;
 | |
| }
 | |
| 
 | |
| AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "A-law Coder/Decoder",
 | |
| 	.support_level = AST_MODULE_SUPPORT_CORE,
 | |
| 	.load = load_module,
 | |
| 	.unload = unload_module,
 | |
| );
 |