Wed Aug 18 22:34:20 2010

Asterisk developer's documentation


codec_ilbc.c File Reference

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

#include "asterisk.h"
#include "asterisk/translate.h"
#include "asterisk/module.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 , .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 = "a9c98e5d177805051735cb5b0b16b0a0" , .load = load_module, .unload = unload_module, }
static 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 53 of file codec_ilbc.c.

#define ILBC_FRAME_LEN   50

Definition at line 51 of file codec_ilbc.c.

Referenced by ilbctolin_framein(), and lintoilbc_frameout().

#define ILBC_MS   30

Definition at line 48 of file codec_ilbc.c.

Referenced by ilbctolin_new(), and lintoilbc_new().

#define ILBC_SAMPLES   240

Definition at line 52 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 47 of file codec_ilbc.c.

Referenced by ilbctolin_new().


Function Documentation

static void __reg_module ( void   )  [static]

Definition at line 244 of file codec_ilbc.c.

static void __unreg_module ( void   )  [static]

Definition at line 244 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 110 of file codec_ilbc.c.

References ast_log(), BUFFER_SAMPLES, ast_trans_pvt::datalen, ilbc_coder_pvt::dec, f, ast_trans_pvt::i16, ILBC_FRAME_LEN, ILBC_SAMPLES, LOG_DEBUG, LOG_WARNING, ast_trans_pvt::outbuf, ast_trans_pvt::pvt, and ast_trans_pvt::samples.

00111 {
00112    struct ilbc_coder_pvt *tmp = pvt->pvt;
00113    int plc_mode = 1; /* 1 = normal data, 0 = plc */
00114    /* Assuming there's space left, decode into the current buffer at
00115       the tail location.  Read in as many frames as there are */
00116    int x,i;
00117    int16_t *dst = pvt->outbuf.i16;
00118    float tmpf[ILBC_SAMPLES];
00119 
00120    if (!f->data.ptr && f->datalen) {
00121       ast_log(LOG_DEBUG, "issue 16070, ILIB ERROR. data = NULL datalen = %d src = %s\n", f->datalen, f->src ? f->src : "no src set");
00122       f->datalen = 0;
00123    }
00124 
00125    if (f->datalen == 0) { /* native PLC, set fake f->datalen and clear plc_mode */
00126       f->datalen = ILBC_FRAME_LEN;
00127       f->samples = ILBC_SAMPLES;
00128       plc_mode = 0;  /* do native plc */
00129       pvt->samples += ILBC_SAMPLES;
00130    }
00131 
00132    if (f->datalen % ILBC_FRAME_LEN) {
00133       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);
00134       return -1;
00135    }
00136    
00137    for (x=0; x < f->datalen ; x += ILBC_FRAME_LEN) {
00138       if (pvt->samples + ILBC_SAMPLES > BUFFER_SAMPLES) {   
00139          ast_log(LOG_WARNING, "Out of buffer space\n");
00140          return -1;
00141       }     
00142       iLBC_decode(tmpf, plc_mode ? f->data.ptr + x : NULL, &tmp->dec, plc_mode);
00143       for ( i=0; i < ILBC_SAMPLES; i++)
00144          dst[pvt->samples + i] = tmpf[i];
00145       pvt->samples += ILBC_SAMPLES;
00146       pvt->datalen += 2*ILBC_SAMPLES;
00147    }
00148    return 0;
00149 }

static int ilbctolin_new ( struct ast_trans_pvt pvt  )  [static]

Definition at line 71 of file codec_ilbc.c.

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

00072 {
00073    struct ilbc_coder_pvt *tmp = pvt->pvt;
00074 
00075    initDecode(&tmp->dec, ILBC_MS, USE_ILBC_ENHANCER);
00076 
00077    return 0;
00078 }

static struct ast_frame* ilbctolin_sample ( void   )  [static]

Definition at line 94 of file codec_ilbc.c.

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

00095 {
00096    static struct ast_frame f;
00097    f.frametype = AST_FRAME_VOICE;
00098    f.subclass = AST_FORMAT_ILBC;
00099    f.datalen = sizeof(ilbc_slin_ex);
00100    /* All frames are 30 ms long */
00101    f.samples = ILBC_SAMPLES;
00102    f.mallocd = 0;
00103    f.offset = 0;
00104    f.src = __PRETTY_FUNCTION__;
00105    f.data.ptr = ilbc_slin_ex;
00106    return &f;
00107 }

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 152 of file codec_ilbc.c.

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

00153 {
00154    struct ilbc_coder_pvt *tmp = pvt->pvt;
00155 
00156    /* Just add the frames to our stream */
00157    /* XXX We should look at how old the rest of our stream is, and if it
00158       is too old, then we should overwrite it entirely, otherwise we can
00159       get artifacts of earlier talk that do not belong */
00160    memcpy(tmp->buf + pvt->samples, f->data.ptr, f->datalen);
00161    pvt->samples += f->samples;
00162    return 0;
00163 }

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

encode the temporary buffer and generate a frame

Definition at line 166 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, ast_trans_pvt::samples, and ast_trans_pvt::uc.

00167 {
00168    struct ilbc_coder_pvt *tmp = pvt->pvt;
00169    int datalen = 0;
00170    int samples = 0;
00171 
00172    /* We can't work on anything less than a frame in size */
00173    if (pvt->samples < ILBC_SAMPLES)
00174       return NULL;
00175    while (pvt->samples >= ILBC_SAMPLES) {
00176       float tmpf[ILBC_SAMPLES];
00177       int i;
00178 
00179       /* Encode a frame of data */
00180       for (i = 0 ; i < ILBC_SAMPLES ; i++)
00181          tmpf[i] = tmp->buf[samples + i];
00182       iLBC_encode( pvt->outbuf.uc + datalen, tmpf, &tmp->enc);
00183 
00184       datalen += ILBC_FRAME_LEN;
00185       samples += ILBC_SAMPLES;
00186       pvt->samples -= ILBC_SAMPLES;
00187    }
00188 
00189    /* Move the data at the end of the buffer to the front */
00190    if (pvt->samples)
00191       memmove(tmp->buf, tmp->buf + samples, pvt->samples * 2);
00192 
00193    return ast_trans_frameout(pvt, datalen, samples);
00194 }

static int lintoilbc_new ( struct ast_trans_pvt pvt  )  [static]

Definition at line 62 of file codec_ilbc.c.

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

00063 {
00064    struct ilbc_coder_pvt *tmp = pvt->pvt;
00065 
00066    initEncode(&tmp->enc, ILBC_MS);
00067 
00068    return 0;
00069 }

static struct ast_frame* lintoilbc_sample ( void   )  [static]

Definition at line 80 of file codec_ilbc.c.

References AST_FORMAT_SLINEAR, AST_FRAME_VOICE, f, and slin_ilbc_ex.

00081 {
00082    static struct ast_frame f;
00083    f.frametype = AST_FRAME_VOICE;
00084    f.subclass = AST_FORMAT_SLINEAR;
00085    f.datalen = sizeof(slin_ilbc_ex);
00086    f.samples = sizeof(slin_ilbc_ex)/2;
00087    f.mallocd = 0;
00088    f.offset = 0;
00089    f.src = __PRETTY_FUNCTION__;
00090    f.data.ptr = slin_ilbc_ex;
00091    return &f;
00092 }

static int load_module ( void   )  [static]

Definition at line 230 of file codec_ilbc.c.

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

00231 {
00232    int res;
00233 
00234    res = ast_register_translator(&ilbctolin);
00235    if (!res) 
00236       res=ast_register_translator(&lintoilbc);
00237    else
00238       ast_unregister_translator(&ilbctolin);
00239    if (res)
00240       return AST_MODULE_LOAD_FAILURE;
00241    return AST_MODULE_LOAD_SUCCESS;
00242 }

static int unload_module ( void   )  [static]

Definition at line 220 of file codec_ilbc.c.

References ast_unregister_translator(), ilbctolin, and lintoilbc.

00221 {
00222    int res;
00223 
00224    res = ast_unregister_translator(&lintoilbc);
00225    res |= ast_unregister_translator(&ilbctolin);
00226 
00227    return res;
00228 }


Variable Documentation

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_DEFAULT , .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 = "a9c98e5d177805051735cb5b0b16b0a0" , .load = load_module, .unload = unload_module, } [static]

Definition at line 244 of file codec_ilbc.c.

struct ast_module_info* ast_module_info = &__mod_info [static]

Definition at line 244 of file codec_ilbc.c.

struct ast_translator ilbctolin [static]

Definition at line 196 of file codec_ilbc.c.

Referenced by load_module(), and unload_module().

struct ast_translator lintoilbc [static]

Definition at line 208 of file codec_ilbc.c.

Referenced by load_module(), and unload_module().


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