codec_a_mu.c File Reference

codec_a_mu.c - translate between alaw and ulaw directly More...

#include "asterisk.h"
#include "asterisk/module.h"
#include "asterisk/translate.h"
#include "asterisk/alaw.h"
#include "asterisk/ulaw.h"
#include "asterisk/utils.h"
#include "ex_ulaw.h"
#include "ex_alaw.h"

Include dependency graph for codec_a_mu.c:

Go to the source code of this file.

Defines
#define	BUFFER_SAMPLES   8000
Functions
static void	__reg_module (void)
static void	__unreg_module (void)
static int	alawtoulaw_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	convert frame data and store into the buffer
static int	load_module (void)
static int	ulawtoalaw_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	convert frame data and store into the buffer
static int	unload_module (void)
	standard module glue
Variables
static struct ast_module_info	__mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "A-law and Mulaw direct Coder/Decoder" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, }
static unsigned char	a2mu [256]
static struct ast_translator	alawtoulaw
static struct ast_module_info *	ast_module_info = &__mod_info
static unsigned char	mu2a [256]
static struct ast_translator	ulawtoalaw

---

Detailed Description

codec_a_mu.c - translate between alaw and ulaw directly

Definition in file codec_a_mu.c.

---

Define Documentation

#define BUFFER_SAMPLES   8000

Definition at line 40 of file codec_a_mu.c.

---

Function Documentation

static void __reg_module

(

void

)

[static]

Definition at line 132 of file codec_a_mu.c.

static void __unreg_module

(

void

)

[static]

Definition at line 132 of file codec_a_mu.c.

static int alawtoulaw_framein	(	struct ast_trans_pvt *	pvt,
		struct ast_frame *	f
	)		[static]

convert frame data and store into the buffer

Definition at line 50 of file codec_a_mu.c.

References ast_frame::data, ast_trans_pvt::datalen, ast_trans_pvt::outbuf, ast_frame::ptr, ast_trans_pvt::samples, ast_frame::samples, and ast_trans_pvt::uc.

{
   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;
}

static int load_module

(

void

)

[static]

Definition at line 113 of file codec_a_mu.c.

References AST_ALAW, AST_LIN2A, AST_LIN2MU, AST_MODULE_LOAD_FAILURE, AST_MODULE_LOAD_SUCCESS, AST_MULAW, ast_register_translator, and ast_unregister_translator().

{
   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;
}

static int ulawtoalaw_framein	(	struct ast_trans_pvt *	pvt,
		struct ast_frame *	f
	)		[static]

convert frame data and store into the buffer

Definition at line 66 of file codec_a_mu.c.

References ast_frame::data, ast_trans_pvt::datalen, ast_trans_pvt::outbuf, ast_frame::ptr, ast_trans_pvt::samples, ast_frame::samples, and ast_trans_pvt::uc.

{
   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 int unload_module

(

void

)

[static]

standard module glue

Definition at line 103 of file codec_a_mu.c.

References ast_unregister_translator().

{
   int res;

   res = ast_unregister_translator(&ulawtoalaw);
   res |= ast_unregister_translator(&alawtoulaw);

   return res;
}

---

Variable Documentation

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "A-law and Mulaw direct Coder/Decoder" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, } [static]

Definition at line 132 of file codec_a_mu.c.

unsigned char a2mu[256] [static]

Definition at line 43 of file codec_a_mu.c.

struct ast_translator alawtoulaw [static]

Definition at line 81 of file codec_a_mu.c.

struct ast_module_info* ast_module_info = &__mod_info [static]

Definition at line 132 of file codec_a_mu.c.

unsigned char mu2a[256] [static]

Definition at line 42 of file codec_a_mu.c.

struct ast_translator ulawtoalaw [static]

Definition at line 91 of file codec_a_mu.c.