Sat Aug 6 00:39:54 2011

Asterisk developer's documentation


codec_ilbc.c File Reference

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

#include "asterisk.h"
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <netinet/in.h>
#include <string.h>
#include <stdio.h>
#include "asterisk/lock.h"
#include "asterisk/translate.h"
#include "asterisk/module.h"
#include "asterisk/logger.h"
#include "asterisk/channel.h"
#include "asterisk/utils.h"
#include "ilbc/iLBC_encode.h"
#include "ilbc/iLBC_decode.h"
#include "slin_ilbc_ex.h"
#include "ilbc_slin_ex.h"

Go to the source code of this file.

Data Structures

struct  ilbc_coder_pvt

Defines

#define BUFFER_SAMPLES   8000
#define ILBC_FRAME_LEN   50
#define ILBC_MS   30
#define ILBC_SAMPLES   240
#define USE_ILBC_ENHANCER   0

Functions

static void __reg_module (void)
static void __unreg_module (void)
static int ilbctolin_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
 decode a frame and store in outbuf
static int ilbctolin_new (struct ast_trans_pvt *pvt)
static struct ast_frameilbctolin_sample (void)
static int lintoilbc_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
 store a frame into a temporary buffer, for later decoding
static struct ast_framelintoilbc_frameout (struct ast_trans_pvt *pvt)
 encode the temporary buffer and generate a frame
static int lintoilbc_new (struct ast_trans_pvt *pvt)
static struct ast_framelintoilbc_sample (void)
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 | AST_MODFLAG_BUILDSUM, .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 = "361d7bb937402d51e4658efb5b4d76e4" , .load = load_module, .unload = unload_module, }
static const struct ast_module_infoast_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.


Define Documentation

#define BUFFER_SAMPLES   8000

Definition at line 63 of file codec_ilbc.c.

#define ILBC_FRAME_LEN   50

Definition at line 61 of file codec_ilbc.c.

Referenced by ilbctolin_framein(), and lintoilbc_frameout().

#define ILBC_MS   30

Definition at line 58 of file codec_ilbc.c.

Referenced by ilbctolin_new(), and lintoilbc_new().

#define ILBC_SAMPLES   240

Definition at line 62 of file codec_ilbc.c.

Referenced by ilbc_read(), ilbc_seek(), ilbc_tell(), ilbctolin_framein(), ilbctolin_sample(), and lintoilbc_frameout().

#define USE_ILBC_ENHANCER   0

Definition at line 57 of file codec_ilbc.c.

Referenced by ilbctolin_new().


Function Documentation

static void __reg_module ( void   )  [static]

Definition at line 253 of file codec_ilbc.c.

static void __unreg_module ( void   )  [static]

Definition at line 253 of file codec_ilbc.c.

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

decode a frame and store in outbuf

Definition at line 120 of file codec_ilbc.c.

References ast_log(), BUFFER_SAMPLES, ast_trans_pvt::datalen, ilbc_coder_pvt::dec, f, ILBC_FRAME_LEN, ILBC_SAMPLES, LOG_DEBUG, LOG_WARNING, ast_trans_pvt::outbuf, ast_trans_pvt::pvt, and ast_trans_pvt::samples.

00121 {
00122    struct ilbc_coder_pvt *tmp = pvt->pvt;
00123    int plc_mode = 1; /* 1 = normal data, 0 = plc */
00124    /* Assuming there's space left, decode into the current buffer at
00125       the tail location.  Read in as many frames as there are */
00126    int x,i;
00127    int16_t *dst = (int16_t *)pvt->outbuf;
00128    float tmpf[ILBC_SAMPLES];
00129 
00130    if (!f->data && f->datalen) {
00131       ast_log(LOG_DEBUG, "issue 16070, ILIB ERROR. data = NULL datalen = %d src = %s\n", f->datalen, f->src ? f->src : "no src set");
00132       f->datalen = 0;
00133    }
00134 
00135    if (f->datalen == 0) { /* native PLC, set fake f->datalen and clear plc_mode */
00136       f->datalen = ILBC_FRAME_LEN;
00137       f->samples = ILBC_SAMPLES;
00138       plc_mode = 0;  /* do native plc */
00139       pvt->samples += ILBC_SAMPLES;
00140    }
00141 
00142    if (f->datalen % ILBC_FRAME_LEN) {
00143       ast_log(LOG_WARNING, "Huh?  An ilbc frame that isn't a multiple of 50 bytes long from %s (%d)?\n", f->src, f->datalen);
00144       return -1;
00145    }
00146    
00147    for (x=0; x < f->datalen ; x += ILBC_FRAME_LEN) {
00148       if (pvt->samples + ILBC_SAMPLES > BUFFER_SAMPLES) {   
00149          ast_log(LOG_WARNING, "Out of buffer space\n");
00150          return -1;
00151       }     
00152       iLBC_decode(tmpf, plc_mode ? f->data + x : NULL, &tmp->dec, plc_mode);
00153       for ( i=0; i < ILBC_SAMPLES; i++)
00154          dst[pvt->samples + i] = tmpf[i];
00155       pvt->samples += ILBC_SAMPLES;
00156       pvt->datalen += 2*ILBC_SAMPLES;
00157    }
00158    return 0;
00159 }

static int ilbctolin_new ( struct ast_trans_pvt pvt  )  [static]

Definition at line 81 of file codec_ilbc.c.

References ilbc_coder_pvt::dec, ILBC_MS, ast_trans_pvt::pvt, and USE_ILBC_ENHANCER.

00082 {
00083    struct ilbc_coder_pvt *tmp = pvt->pvt;
00084 
00085    initDecode(&tmp->dec, ILBC_MS, USE_ILBC_ENHANCER);
00086 
00087    return 0;
00088 }

static struct ast_frame* ilbctolin_sample ( void   )  [static]

Definition at line 104 of file codec_ilbc.c.

References AST_FORMAT_ILBC, AST_FRAME_VOICE, f, ILBC_SAMPLES, and ilbc_slin_ex.

00105 {
00106    static struct ast_frame f;
00107    f.frametype = AST_FRAME_VOICE;
00108    f.subclass = AST_FORMAT_ILBC;
00109    f.datalen = sizeof(ilbc_slin_ex);
00110    /* All frames are 30 ms long */
00111    f.samples = ILBC_SAMPLES;
00112    f.mallocd = 0;
00113    f.offset = 0;
00114    f.src = __PRETTY_FUNCTION__;
00115    f.data = ilbc_slin_ex;
00116    return &f;
00117 }

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 162 of file codec_ilbc.c.

References ilbc_coder_pvt::buf, f, ast_trans_pvt::pvt, and ast_trans_pvt::samples.

00163 {
00164    struct ilbc_coder_pvt *tmp = pvt->pvt;
00165 
00166    /* Just add the frames to our stream */
00167    /* XXX We should look at how old the rest of our stream is, and if it
00168       is too old, then we should overwrite it entirely, otherwise we can
00169       get artifacts of earlier talk that do not belong */
00170    memcpy(tmp->buf + pvt->samples, f->data, f->datalen);
00171    pvt->samples += f->samples;
00172    return 0;
00173 }

static struct ast_frame* lintoilbc_frameout ( struct ast_trans_pvt pvt  )  [static]

encode the temporary buffer and generate a frame

Definition at line 176 of file codec_ilbc.c.

References ast_trans_frameout(), ilbc_coder_pvt::buf, ilbc_coder_pvt::enc, ILBC_FRAME_LEN, ILBC_SAMPLES, ast_trans_pvt::outbuf, ast_trans_pvt::pvt, and ast_trans_pvt::samples.

00177 {
00178    struct ilbc_coder_pvt *tmp = pvt->pvt;
00179    int datalen = 0;
00180    int samples = 0;
00181 
00182    /* We can't work on anything less than a frame in size */
00183    if (pvt->samples < ILBC_SAMPLES)
00184       return NULL;
00185    while (pvt->samples >= ILBC_SAMPLES) {
00186       float tmpf[ILBC_SAMPLES];
00187       int i;
00188 
00189       /* Encode a frame of data */
00190       for (i = 0 ; i < ILBC_SAMPLES ; i++)
00191          tmpf[i] = tmp->buf[samples + i];
00192       iLBC_encode((unsigned char *) pvt->outbuf + datalen, tmpf, &tmp->enc);
00193 
00194       datalen += ILBC_FRAME_LEN;
00195       samples += ILBC_SAMPLES;
00196       pvt->samples -= ILBC_SAMPLES;
00197    }
00198 
00199    /* Move the data at the end of the buffer to the front */
00200    if (pvt->samples)
00201       memmove(tmp->buf, tmp->buf + samples, pvt->samples * 2);
00202 
00203    return ast_trans_frameout(pvt, datalen, samples);
00204 }

static int lintoilbc_new ( struct ast_trans_pvt pvt  )  [static]

Definition at line 72 of file codec_ilbc.c.

References ilbc_coder_pvt::enc, ILBC_MS, and ast_trans_pvt::pvt.

00073 {
00074    struct ilbc_coder_pvt *tmp = pvt->pvt;
00075 
00076    initEncode(&tmp->enc, ILBC_MS);
00077 
00078    return 0;
00079 }

static struct ast_frame* lintoilbc_sample ( void   )  [static]

Definition at line 90 of file codec_ilbc.c.

References AST_FORMAT_SLINEAR, AST_FRAME_VOICE, f, and slin_ilbc_ex.

00091 {
00092    static struct ast_frame f;
00093    f.frametype = AST_FRAME_VOICE;
00094    f.subclass = AST_FORMAT_SLINEAR;
00095    f.datalen = sizeof(slin_ilbc_ex);
00096    f.samples = sizeof(slin_ilbc_ex)/2;
00097    f.mallocd = 0;
00098    f.offset = 0;
00099    f.src = __PRETTY_FUNCTION__;
00100    f.data = slin_ilbc_ex;
00101    return &f;
00102 }

static int load_module ( void   )  [static]

Definition at line 240 of file codec_ilbc.c.

References ast_register_translator, ast_unregister_translator(), ilbctolin, and lintoilbc.

00241 {
00242    int res;
00243 
00244    res = ast_register_translator(&ilbctolin);
00245    if (!res) 
00246       res=ast_register_translator(&lintoilbc);
00247    else
00248       ast_unregister_translator(&ilbctolin);
00249 
00250    return res;
00251 }

static int unload_module ( void   )  [static]

Definition at line 230 of file codec_ilbc.c.

References ast_unregister_translator(), ilbctolin, and lintoilbc.

00231 {
00232    int res;
00233 
00234    res = ast_unregister_translator(&lintoilbc);
00235    res |= ast_unregister_translator(&ilbctolin);
00236 
00237    return res;
00238 }


Variable Documentation

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_DEFAULT | AST_MODFLAG_BUILDSUM, .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 = "361d7bb937402d51e4658efb5b4d76e4" , .load = load_module, .unload = unload_module, } [static]

Definition at line 253 of file codec_ilbc.c.

const struct ast_module_info* ast_module_info = &__mod_info [static]

Definition at line 253 of file codec_ilbc.c.

struct ast_translator ilbctolin [static]

Definition at line 206 of file codec_ilbc.c.

Referenced by load_module(), and unload_module().

struct ast_translator lintoilbc [static]

Definition at line 218 of file codec_ilbc.c.

Referenced by load_module(), and unload_module().


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