codec_ilbc.c File Reference

Translate between signed linear and Internet Low Bitrate Codec. More...

#include "asterisk.h"
#include "asterisk/codec.h"
#include "asterisk/format.h"
#include "asterisk/frame.h"
#include "asterisk/linkedlists.h"
#include "asterisk/logger.h"
#include "asterisk/module.h"
#include "asterisk/translate.h"
#include "ilbc/iLBC_encode.h"
#include "ilbc/iLBC_decode.h"
#include "asterisk/ilbc.h"
#include "asterisk/slin.h"
#include "ex_ilbc.h"

Include dependency graph for codec_ilbc.c:

Go to the source code of this file.

Data Structures
struct	ilbc_coder_pvt

Macros
#define	BUF_TYPE   uc
#define	BUFFER_SAMPLES   8000
#define	USE_ILBC_ENHANCER   0

Typedefs
typedef float	ilbc_block
typedef unsigned char	ilbc_bytes

Functions
static void	__reg_module (void)
static void	__unreg_module (void)
struct ast_module *	AST_MODULE_SELF_SYM (void)
static int	ilbctolin_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	decode a frame and store in outbuf More...
static int	ilbctolin_new (struct ast_trans_pvt *pvt)
static int	lintoilbc_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	store a frame into a temporary buffer, for later decoding More...
static struct ast_frame *	lintoilbc_frameout (struct ast_trans_pvt *pvt)
	encode the temporary buffer and generate a frame More...
static int	lintoilbc_new (struct ast_trans_pvt *pvt)
static int	load_module (void)
static int	unload_module (void)

Variables
static struct ast_module_info	__mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "iLBC 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, .support_level = AST_MODULE_SUPPORT_CORE, }
static const struct ast_module_info *	ast_module_info = &__mod_info
static struct ast_translator	ilbctolin
static struct ast_translator	lintoilbc

Detailed Description

Translate between signed linear and Internet Low Bitrate Codec.

Definition in file codec_ilbc.c.

Macro Definition Documentation

BUF_TYPE

#define BUF_TYPE   uc

Definition at line 53 of file codec_ilbc.c.

BUFFER_SAMPLES

#define BUFFER_SAMPLES   8000

Definition at line 59 of file codec_ilbc.c.

USE_ILBC_ENHANCER

#define USE_ILBC_ENHANCER   0

Definition at line 58 of file codec_ilbc.c.

Typedef Documentation

ilbc_block

typedef float ilbc_block

Definition at line 52 of file codec_ilbc.c.

ilbc_bytes

typedef unsigned char ilbc_bytes

Definition at line 51 of file codec_ilbc.c.

Function Documentation

__reg_module()

static void __reg_module ( void  )

static

Definition at line 276 of file codec_ilbc.c.

__unreg_module()

static void __unreg_module ( void  )

static

Definition at line 276 of file codec_ilbc.c.

AST_MODULE_SELF_SYM()

struct ast_module * AST_MODULE_SELF_SYM

(

void

)

Definition at line 276 of file codec_ilbc.c.

ilbctolin_framein()

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

static

decode a frame and store in outbuf

Definition at line 94 of file codec_ilbc.c.

{
    struct ilbc_coder_pvt *tmp = pvt->pvt;
    struct ilbc_attr *attr = ast_format_get_attribute_data(f->subclass.format);
    const unsigned int mode = attr ? attr->mode : 30;
    const unsigned int sample_rate = pvt->t->dst_codec.sample_rate;
    const unsigned int samples_per_frame = mode * sample_rate / 1000;
    const unsigned int octets_per_frame = (mode == 20) ? 38 : 50;
 
    int plc_mode = 1; /* 1 = normal data, 0 = plc */
    /* Assuming there's space left, decode into the current buffer at
       the tail location.  Read in as many frames as there are */
    int x,i;
    int datalen = f->datalen;
    int16_t *dst = pvt->outbuf.i16;
    ilbc_block tmpf[samples_per_frame];
 
    if (!f->data.ptr && datalen) {
        ast_debug(1, "issue 16070, ILIB ERROR. data = NULL datalen = %d src = %s\n", datalen, f->src ? f->src : "no src set");
        f->datalen = 0;
        datalen = 0;
    }
 
    if (datalen == 0) { /* native PLC, set fake datalen and clear plc_mode */
        datalen = octets_per_frame;
        f->samples = samples_per_frame;
        plc_mode = 0;   /* do native plc */
        pvt->samples += samples_per_frame;
    }
 
    if (datalen % octets_per_frame) {
        ast_log(LOG_WARNING, "Huh?  An ilbc frame that isn't a multiple of %u bytes long from %s (%d)?\n", octets_per_frame, f->src, datalen);
        return -1;
    }
 
    if (!tmp->inited) {
        initDecode(&tmp->dec, mode, USE_ILBC_ENHANCER);
        tmp->inited = 1;
    }
 
    for (x = 0; x < datalen; x += octets_per_frame) {
        if (pvt->samples + samples_per_frame > BUFFER_SAMPLES) {
            ast_log(LOG_WARNING, "Out of buffer space\n");
            return -1;
        }
        iLBC_decode(tmpf, plc_mode ? f->data.ptr + x : NULL, &tmp->dec, plc_mode);
        for (i = 0; i < samples_per_frame; i++)
            dst[pvt->samples + i] = tmpf[i];
        pvt->samples += samples_per_frame;
        pvt->datalen += samples_per_frame * 2;
    }
    return 0;
}

References ast_debug, ast_format_get_attribute_data(), ast_log, BUFFER_SAMPLES, ast_frame::data, ast_frame::datalen, ast_trans_pvt::datalen, ast_translator::dst_codec, ast_frame_subclass::format, ast_trans_pvt::i16, iLBC_decode(), initDecode(), LOG_WARNING, ilbc_attr::mode, NULL, ast_trans_pvt::outbuf, ast_frame::ptr, ast_trans_pvt::pvt, ast_codec::sample_rate, ast_frame::samples, ast_trans_pvt::samples, ast_frame::src, ast_frame::subclass, ast_trans_pvt::t, tmp(), and USE_ILBC_ENHANCER.

ilbctolin_new()

static int ilbctolin_new ( struct ast_trans_pvt *  pvt )

static

Definition at line 84 of file codec_ilbc.c.

{
    struct ilbc_coder_pvt *tmp = pvt->pvt;
 
    tmp->inited = 0; /* we do not know the iLBC mode, yet */
 
    return 0;
}

References ast_trans_pvt::pvt, and tmp().

lintoilbc_framein()

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

static

store a frame into a temporary buffer, for later decoding

Definition at line 149 of file codec_ilbc.c.

{
    struct ilbc_coder_pvt *tmp = pvt->pvt;
 
    /* Just add the frames to our stream */
    /* XXX We should look at how old the rest of our stream is, and if it
       is too old, then we should overwrite it entirely, otherwise we can
       get artifacts of earlier talk that do not belong */
    memcpy(tmp->buf + pvt->samples, f->data.ptr, f->datalen);
    pvt->samples += f->samples;
    return 0;
}

References ast_frame::data, ast_frame::datalen, ast_frame::ptr, ast_trans_pvt::pvt, ast_frame::samples, ast_trans_pvt::samples, and tmp().

lintoilbc_frameout()

static struct ast_frame * lintoilbc_frameout ( struct ast_trans_pvt *  pvt )

static

encode the temporary buffer and generate a frame

Definition at line 163 of file codec_ilbc.c.

{
    struct ilbc_coder_pvt *tmp = pvt->pvt;
    struct ast_frame *result = NULL;
    struct ast_frame *last = NULL;
    int samples = 0; /* output samples */
 
    struct ilbc_attr *attr = ast_format_get_attribute_data(pvt->f.subclass.format);
    const unsigned int mode = attr ? attr->mode : 30;
    const unsigned int sample_rate = pvt->t->dst_codec.sample_rate;
    const unsigned int samples_per_frame = mode * sample_rate / 1000;
    const unsigned int octets_per_frame = (mode == 20) ? 38 : 50;
 
    while (pvt->samples >= samples_per_frame) {
        struct ast_frame *current;
        ilbc_block tmpf[samples_per_frame];
        int i;
 
        /* Encode a frame of data */
        for (i = 0; i < samples_per_frame; i++)
            tmpf[i] = tmp->buf[samples + i];
        iLBC_encode((ilbc_bytes *) pvt->outbuf.BUF_TYPE, tmpf, &tmp->enc);
 
        samples += samples_per_frame;
        pvt->samples -= samples_per_frame;
 
        current = ast_trans_frameout(pvt, octets_per_frame, samples_per_frame);
        if (!current) {
            continue;
        } else if (last) {
            AST_LIST_NEXT(last, frame_list) = current;
        } else {
            result = current;
        }
        last = current;
    }
 
    /* Move the data at the end of the buffer to the front */
    if (samples) {
        memmove(tmp->buf, tmp->buf + samples, pvt->samples * 2);
    }
 
    return result;
}

References ast_format_get_attribute_data(), AST_LIST_NEXT, ast_trans_frameout(), current, ast_translator::dst_codec, ast_trans_pvt::f, ast_frame_subclass::format, iLBC_encode(), last, ilbc_attr::mode, NULL, ast_trans_pvt::outbuf, ast_trans_pvt::pvt, result, ast_codec::sample_rate, ast_frame::samples, ast_trans_pvt::samples, ast_frame::subclass, ast_trans_pvt::t, and tmp().

lintoilbc_new()

static int lintoilbc_new ( struct ast_trans_pvt *  pvt )

static

Definition at line 73 of file codec_ilbc.c.

{
    struct ilbc_coder_pvt *tmp = pvt->pvt;
    struct ilbc_attr *attr = pvt->explicit_dst ? ast_format_get_attribute_data(pvt->explicit_dst) : NULL;
    const unsigned int mode = attr ? attr->mode : 30;
 
    initEncode(&tmp->enc, mode);
 
    return 0;
}

References ast_format_get_attribute_data(), ast_trans_pvt::explicit_dst, initEncode(), ilbc_attr::mode, NULL, ast_trans_pvt::pvt, and tmp().

load_module()

static int load_module ( void  )

static

Definition at line 261 of file codec_ilbc.c.

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

References AST_MODULE_LOAD_DECLINE, AST_MODULE_LOAD_SUCCESS, ast_register_translator, ilbctolin, lintoilbc, and unload_module().

unload_module()

static int unload_module ( void  )

static

Definition at line 251 of file codec_ilbc.c.

{
    int res;
 
    res = ast_unregister_translator(&lintoilbc);
    res |= ast_unregister_translator(&ilbctolin);
 
    return res;
}

References ast_unregister_translator(), ilbctolin, and lintoilbc.

Referenced by load_module().

Variable Documentation

__mod_info

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "iLBC 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, .support_level = AST_MODULE_SUPPORT_CORE, }

static

Definition at line 276 of file codec_ilbc.c.

ast_module_info

const struct ast_module_info* ast_module_info = &__mod_info

static

Definition at line 276 of file codec_ilbc.c.

ilbctolin

struct ast_translator ilbctolin

static

Definition at line 208 of file codec_ilbc.c.

Referenced by load_module(), and unload_module().

lintoilbc

struct ast_translator lintoilbc

static

Definition at line 229 of file codec_ilbc.c.

Referenced by load_module(), and unload_module().