Thu Apr 28 2011 17:13:55

Asterisk developer's documentation


format_g729.c File Reference

Save to raw, headerless G729 data. More...

#include "asterisk.h"
#include "asterisk/mod_format.h"
#include "asterisk/module.h"
#include "asterisk/endian.h"
Include dependency graph for format_g729.c:

Go to the source code of this file.

Defines

#define BUF_SIZE   20
#define G729A_SAMPLES   160

Functions

static void __reg_module (void)
static void __unreg_module (void)
static struct ast_frameg729_read (struct ast_filestream *s, int *whennext)
static int g729_seek (struct ast_filestream *fs, off_t sample_offset, int whence)
static off_t g729_tell (struct ast_filestream *fs)
static int g729_trunc (struct ast_filestream *fs)
static int g729_write (struct ast_filestream *fs, struct ast_frame *f)
static int load_module (void)
static int unload_module (void)

Variables

static struct ast_module_info
__MODULE_INFO_SECTION 
__mod_info = { __MODULE_INFO_GLOBALS .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Raw G729 data" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = 10, }
static struct ast_module_infoast_module_info = &__mod_info
static struct ast_format g729_f

Detailed Description

Save to raw, headerless G729 data.

Note:
This is not an encoder/decoder. The codec fo g729 is only available with a commercial license from Digium, due to patent restrictions. Check http://www.digium.com for information.
  • Extensions: g729

Definition in file format_g729.c.


Define Documentation

#define BUF_SIZE   20

Definition at line 41 of file format_g729.c.

Referenced by g729_read(), g729_seek(), and g729_tell().

#define G729A_SAMPLES   160

Definition at line 42 of file format_g729.c.

Referenced by g729_read(), g729_seek(), and g729_tell().


Function Documentation

static void __reg_module ( void  ) [static]

Definition at line 152 of file format_g729.c.

static void __unreg_module ( void  ) [static]

Definition at line 152 of file format_g729.c.

static struct ast_frame* g729_read ( struct ast_filestream s,
int *  whennext 
) [static, read]

Definition at line 44 of file format_g729.c.

References AST_FORMAT_G729A, AST_FRAME_SET_BUFFER, AST_FRAME_VOICE, AST_FRIENDLY_OFFSET, ast_log(), ast_filestream::buf, BUF_SIZE, ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_filestream::fr, ast_frame::frametype, G729A_SAMPLES, LOG_WARNING, ast_frame::mallocd, ast_frame::ptr, ast_frame::samples, and ast_frame::subclass.

{
   int res;
   /* Send a frame from the file to the appropriate channel */
   s->fr.frametype = AST_FRAME_VOICE;
   s->fr.subclass = AST_FORMAT_G729A;
   s->fr.mallocd = 0;
   s->fr.samples = G729A_SAMPLES;
   AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, BUF_SIZE);
   if ((res = fread(s->fr.data.ptr, 1, s->fr.datalen, s->f)) != s->fr.datalen) {
      if (res && (res != 10)) /* XXX what for ? */
         ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
      return NULL;
   }
   *whennext = s->fr.samples;
   return &s->fr;
}
static int g729_seek ( struct ast_filestream fs,
off_t  sample_offset,
int  whence 
) [static]

Definition at line 84 of file format_g729.c.

References BUF_SIZE, ast_filestream::f, G729A_SAMPLES, ast_frame::offset, and SEEK_FORCECUR.

{
   long bytes;
   off_t min,cur,max,offset=0;
   min = 0;
   cur = ftello(fs->f);
   fseeko(fs->f, 0, SEEK_END);
   max = ftello(fs->f);
   
   bytes = BUF_SIZE * (sample_offset / G729A_SAMPLES);
   if (whence == SEEK_SET)
      offset = bytes;
   else if (whence == SEEK_CUR || whence == SEEK_FORCECUR)
      offset = cur + bytes;
   else if (whence == SEEK_END)
      offset = max - bytes;
   if (whence != SEEK_FORCECUR) {
      offset = (offset > max)?max:offset;
   }
   /* protect against seeking beyond begining. */
   offset = (offset < min)?min:offset;
   if (fseeko(fs->f, offset, SEEK_SET) < 0)
      return -1;
   return 0;
}
static off_t g729_tell ( struct ast_filestream fs) [static]

Definition at line 118 of file format_g729.c.

References BUF_SIZE, ast_filestream::f, G729A_SAMPLES, and ast_frame::offset.

{
   off_t offset = ftello(fs->f);
   return (offset/BUF_SIZE)*G729A_SAMPLES;
}
static int g729_trunc ( struct ast_filestream fs) [static]

Definition at line 110 of file format_g729.c.

References ast_filestream::f.

{
   /* Truncate file to current length */
   if (ftruncate(fileno(fs->f), ftello(fs->f)) < 0)
      return -1;
   return 0;
}
static int g729_write ( struct ast_filestream fs,
struct ast_frame f 
) [static]

Definition at line 62 of file format_g729.c.

References AST_FORMAT_G729A, AST_FRAME_VOICE, ast_log(), ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_frame::frametype, fwrite, LOG_WARNING, ast_frame::ptr, and ast_frame::subclass.

{
   int res;
   if (f->frametype != AST_FRAME_VOICE) {
      ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
      return -1;
   }
   if (f->subclass != AST_FORMAT_G729A) {
      ast_log(LOG_WARNING, "Asked to write non-G729 frame (%d)!\n", f->subclass);
      return -1;
   }
   if (f->datalen % 10) {
      ast_log(LOG_WARNING, "Invalid data length, %d, should be multiple of 10\n", f->datalen);
      return -1;
   }
   if ((res = fwrite(f->data.ptr, 1, f->datalen, fs->f)) != f->datalen) {
         ast_log(LOG_WARNING, "Bad write (%d/10): %s\n", res, strerror(errno));
         return -1;
   }
   return 0;
}
static int load_module ( void  ) [static]
static int unload_module ( void  ) [static]

Definition at line 143 of file format_g729.c.

References ast_format_unregister(), and ast_format::name.


Variable Documentation

struct ast_module_info __MODULE_INFO_SECTION __mod_info = { __MODULE_INFO_GLOBALS .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Raw G729 data" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = 10, } [static]

Definition at line 152 of file format_g729.c.

Definition at line 152 of file format_g729.c.

struct ast_format g729_f [static]

Definition at line 124 of file format_g729.c.