codec_alaw.c File Reference

codec_alaw.c - translate between signed linear and alaw More...

#include "asterisk.h"
#include "asterisk/module.h"
#include "asterisk/config.h"
#include "asterisk/translate.h"
#include "asterisk/alaw.h"
#include "asterisk/utils.h"
#include "asterisk/slin.h"
#include "ex_alaw.h"

Include dependency graph for codec_alaw.c:

Go to the source code of this file.

Macros
#define	BUFFER_SAMPLES   8096 /* size for the translation buffers */

Functions
static void	__reg_module (void)
static void	__unreg_module (void)
static int	alawtolin_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	decode frame into lin and fill output buffer.
struct ast_module *	AST_MODULE_SELF_SYM (void)
static int	lintoalaw_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	convert and store input samples in output buffer
static int	load_module (void)
static int	unload_module (void)

Variables
static struct ast_module_info	__mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_DEFAULT , .description = "A-law Coder/Decoder" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .support_level = AST_MODULE_SUPPORT_CORE, .load = load_module, .unload = unload_module, }
static struct ast_translator	alawtolin
static const struct ast_module_info *	ast_module_info = &__mod_info
static struct ast_translator	lintoalaw

Detailed Description

codec_alaw.c - translate between signed linear and alaw

Definition in file codec_alaw.c.

Macro Definition Documentation

BUFFER_SAMPLES

#define BUFFER_SAMPLES   8096 /* size for the translation buffers */

Definition at line 38 of file codec_alaw.c.

Function Documentation

__reg_module()

static void __reg_module ( void  )

static

Definition at line 143 of file codec_alaw.c.

__unreg_module()

static void __unreg_module ( void  )

static

Definition at line 143 of file codec_alaw.c.

alawtolin_framein()

static int alawtolin_framein ( struct ast_trans_pvt *  pvt, struct ast_frame *  f  )

static

decode frame into lin and fill output buffer.

Definition at line 45 of file codec_alaw.c.

{
    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;
}

References AST_ALAW, ast_frame::data, ast_trans_pvt::datalen, ast_trans_pvt::i16, ast_trans_pvt::outbuf, ast_frame::ptr, ast_frame::samples, and ast_trans_pvt::samples.

AST_MODULE_SELF_SYM()

struct ast_module * AST_MODULE_SELF_SYM

(

void

)

Definition at line 143 of file codec_alaw.c.

lintoalaw_framein()

static int lintoalaw_framein ( struct ast_trans_pvt *  pvt, struct ast_frame *  f  )

static

convert and store input samples in output buffer

Definition at line 61 of file codec_alaw.c.

{
    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;
}

References AST_LIN2A, ast_trans_pvt::c, ast_frame::data, ast_trans_pvt::datalen, ast_trans_pvt::outbuf, ast_frame::ptr, ast_frame::samples, and ast_trans_pvt::samples.

load_module()

static int load_module ( void  )

static

Definition at line 124 of file codec_alaw.c.

{
    int res;
 
    res = ast_register_translator(&alawtolin);
    res |= ast_register_translator(&lintoalaw);
 
    if (res) {
        unload_module();
        return AST_MODULE_LOAD_DECLINE;
    }
 
    return AST_MODULE_LOAD_SUCCESS;
}

References alawtolin, AST_MODULE_LOAD_DECLINE, AST_MODULE_LOAD_SUCCESS, ast_register_translator, lintoalaw, and unload_module().

unload_module()

static int unload_module ( void  )

static

Definition at line 114 of file codec_alaw.c.

{
    int res;
 
    res = ast_unregister_translator(&lintoalaw);
    res |= ast_unregister_translator(&alawtolin);
 
    return res;
}

References alawtolin, ast_unregister_translator(), and lintoalaw.

Referenced by load_module().

Variable Documentation

__mod_info

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_DEFAULT , .description = "A-law Coder/Decoder" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .support_level = AST_MODULE_SUPPORT_CORE, .load = load_module, .unload = unload_module, }

static

Definition at line 143 of file codec_alaw.c.

alawtolin

struct ast_translator alawtolin

static

Definition at line 76 of file codec_alaw.c.

                                         {
    .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,
};

Referenced by load_module(), and unload_module().

ast_module_info

const struct ast_module_info* ast_module_info = &__mod_info

static

Definition at line 143 of file codec_alaw.c.

lintoalaw

struct ast_translator lintoalaw

static

Definition at line 95 of file codec_alaw.c.

                                         {
    .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,
};

Referenced by load_module(), and unload_module().