Work with WAV in the proprietary Microsoft format. Microsoft WAV format (8000hz Signed Linear) More...

#include "asterisk.h"
#include "asterisk/mod_format.h"
#include "asterisk/module.h"
#include "asterisk/endian.h"

Include dependency graph for format_wav.c:

Go to the source code of this file.

Data Structures
struct	wav_desc
Defines
#define	BLOCKSIZE 160
#define	WAV_BUF_SIZE 320
Functions
static void	__reg_module (void)
static void	__unreg_module (void)
static int	check_header (FILE *f, int hz)
static int	check_header_fmt (FILE *f, int hsize, int hz)
static int	load_module (void)
static int	unload_module (void)
static int	update_header (FILE *f)
static void	wav_close (struct ast_filestream *s)
static int	wav_open (struct ast_filestream *s)
static struct ast_frame *	wav_read (struct ast_filestream s, int whennext)
static int	wav_rewrite (struct ast_filestream s, const char comment)
static int	wav_seek (struct ast_filestream *fs, off_t sample_offset, int whence)
static off_t	wav_tell (struct ast_filestream *fs)
static int	wav_trunc (struct ast_filestream *fs)
static int	wav_write (struct ast_filestream fs, struct ast_frame f)
static int	write_header (FILE *f, int writehz)
Variables
static struct ast_module_info	__mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Microsoft WAV/WAV16 format (8kHz/16kHz Signed Linear)" , .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_APP_DEPEND }
static struct ast_module_info *	ast_module_info = &__mod_info
static struct ast_format	wav16_f
static struct ast_format	wav_f

Detailed Description

Work with WAV in the proprietary Microsoft format. Microsoft WAV format (8000hz Signed Linear)

File name extension: wav (lower case)

Definition in file format_wav.c.

Define Documentation

#define BLOCKSIZE 160

Definition at line 53 of file format_wav.c.

#define WAV_BUF_SIZE 320

Definition at line 43 of file format_wav.c.

Referenced by wav_read().

Function Documentation

static void __reg_module ( void ) [static]

Definition at line 541 of file format_wav.c.

static void __unreg_module ( void ) [static]

Definition at line 541 of file format_wav.c.

static int check_header	(	FILE *	f,
		int	hz
	)		`[static]`

Definition at line 139 of file format_wav.c.

References ast_log(), check_header_fmt(), LOG_DEBUG, LOG_WARNING, and type.

Referenced by wav_open().

{
   int type, size, formtype;
   int data;
   if (fread(&type, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Read failed (type)\n");
      return -1;
   }
   if (fread(&size, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Read failed (size)\n");
      return -1;
   }
   size = ltohl(size);
   if (fread(&formtype, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Read failed (formtype)\n");
      return -1;
   }
   if (memcmp(&type, "RIFF", 4)) {
      ast_log(LOG_WARNING, "Does not begin with RIFF\n");
      return -1;
   }
   if (memcmp(&formtype, "WAVE", 4)) {
      ast_log(LOG_WARNING, "Does not contain WAVE\n");
      return -1;
   }
   /* Skip any facts and get the first data block */
   for(;;)
   { 
      char buf[4];
       
       /* Begin data chunk */
       if (fread(&buf, 1, 4, f) != 4) {
         ast_log(LOG_WARNING, "Read failed (block header format)\n");
         return -1;
       }
       /* Data has the actual length of data in it */
       if (fread(&data, 1, 4, f) != 4) {
         ast_log(LOG_WARNING, "Read failed (block '%.4s' header length)\n", buf);
         return -1;
       }
       data = ltohl(data);
      if (memcmp(&buf, "fmt ", 4) == 0) {
         if (check_header_fmt(f, data, hz))
            return -1;
         continue;
      }
       if(memcmp(buf, "data", 4) == 0 ) 
         break;
      ast_log(LOG_DEBUG, "Skipping unknown block '%.4s'\n", buf);
       if (fseek(f,data,SEEK_CUR) == -1 ) {
         ast_log(LOG_WARNING, "Failed to skip '%.4s' block: %d\n", buf, data);
         return -1;
       }
   }
#if 0
   curpos = lseek(fd, 0, SEEK_CUR);
   truelength = lseek(fd, 0, SEEK_END);
   lseek(fd, curpos, SEEK_SET);
   truelength -= curpos;
#endif   
   return data;
}

static int check_header_fmt	(	FILE *	f,
		int	hsize,
		int	hz
	)		`[static]`

Definition at line 78 of file format_wav.c.

References ast_log(), format, and LOG_WARNING.

Referenced by check_header().

{
   short format, chans, bysam, bisam;
   int bysec;
   int freq;
   if (hsize < 16) {
      ast_log(LOG_WARNING, "Unexpected header size %d\n", hsize);
      return -1;
   }
   if (fread(&format, 1, 2, f) != 2) {
      ast_log(LOG_WARNING, "Read failed (format)\n");
      return -1;
   }
   if (ltohs(format) != 1) {
      ast_log(LOG_WARNING, "Not a wav file %d\n", ltohs(format));
      return -1;
   }
   if (fread(&chans, 1, 2, f) != 2) {
      ast_log(LOG_WARNING, "Read failed (format)\n");
      return -1;
   }
   if (ltohs(chans) != 1) {
      ast_log(LOG_WARNING, "Not in mono %d\n", ltohs(chans));
      return -1;
   }
   if (fread(&freq, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Read failed (freq)\n");
      return -1;
   }
   if (((ltohl(freq) != 8000) && (ltohl(freq) != 16000)) ||
       ((ltohl(freq) == 8000) && (hz != 8000)) ||
       ((ltohl(freq) == 16000) && (hz != 16000))) {
      ast_log(LOG_WARNING, "Unexpected frequency mismatch %d (expecting %d)\n", ltohl(freq),hz);
      return -1;
   }
   /* Ignore the byte frequency */
   if (fread(&bysec, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Read failed (BYTES_PER_SECOND)\n");
      return -1;
   }
   /* Check bytes per sample */
   if (fread(&bysam, 1, 2, f) != 2) {
      ast_log(LOG_WARNING, "Read failed (BYTES_PER_SAMPLE)\n");
      return -1;
   }
   if (ltohs(bysam) != 2) {
      ast_log(LOG_WARNING, "Can only handle 16bits per sample: %d\n", ltohs(bysam));
      return -1;
   }
   if (fread(&bisam, 1, 2, f) != 2) {
      ast_log(LOG_WARNING, "Read failed (Bits Per Sample): %d\n", ltohs(bisam));
      return -1;
   }
   /* Skip any additional header */
   if (fseek(f,hsize-16,SEEK_CUR) == -1 ) {
      ast_log(LOG_WARNING, "Failed to skip remaining header bytes: %d\n", hsize-16 );
      return -1;
   }
   return 0;
}

static int load_module ( void ) [static]

Definition at line 523 of file format_wav.c.

References ast_format_register, AST_MODULE_LOAD_FAILURE, and AST_MODULE_LOAD_SUCCESS.

{
   if (ast_format_register(&wav_f)
      || ast_format_register(&wav16_f))
      return AST_MODULE_LOAD_FAILURE;
   return AST_MODULE_LOAD_SUCCESS;
}

static int unload_module ( void ) [static]

Definition at line 531 of file format_wav.c.

References ast_format_unregister(), and ast_format::name.

{
   return ast_format_unregister(wav_f.name)
      || ast_format_unregister(wav16_f.name);
}

static int update_header ( FILE * f ) [static]

Definition at line 202 of file format_wav.c.

References ast_log(), and LOG_WARNING.

Referenced by wav_close(), and wav_trunc().

{
   off_t cur,end;
   int datalen,filelen,bytes;
   
   cur = ftello(f);
   fseek(f, 0, SEEK_END);
   end = ftello(f);
   /* data starts 44 bytes in */
   bytes = end - 44;
   datalen = htoll(bytes);
   /* chunk size is bytes of data plus 36 bytes of header */
   filelen = htoll(36 + bytes);
   
   if (cur < 0) {
      ast_log(LOG_WARNING, "Unable to find our position\n");
      return -1;
   }
   if (fseek(f, 4, SEEK_SET)) {
      ast_log(LOG_WARNING, "Unable to set our position\n");
      return -1;
   }
   if (fwrite(&filelen, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to set write file size\n");
      return -1;
   }
   if (fseek(f, 40, SEEK_SET)) {
      ast_log(LOG_WARNING, "Unable to set our position\n");
      return -1;
   }
   if (fwrite(&datalen, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to set write datalen\n");
      return -1;
   }
   if (fseeko(f, cur, SEEK_SET)) {
      ast_log(LOG_WARNING, "Unable to return to position\n");
      return -1;
   }
   return 0;
}

static void wav_close ( struct ast_filestream * s ) [static]

Definition at line 338 of file format_wav.c.

References ast_filestream::_private, ast_log(), wav_desc::bytes, errno, ast_filestream::f, ast_filestream::filename, LOG_WARNING, ast_filestream::mode, and update_header().

{
   char zero = 0;
   struct wav_desc *fs = (struct wav_desc *)s->_private;

   if (s->mode == O_RDONLY) {
      return;
   }

   if (s->filename) {
      update_header(s->f);
   }

   /* Pad to even length */
   if (fs->bytes & 0x1) {
      if (!fwrite(&zero, 1, 1, s->f)) {
         ast_log(LOG_WARNING, "fwrite() failed: %s\n", strerror(errno));
      }
   }
}

static int wav_open ( struct ast_filestream * s ) [static]

Definition at line 314 of file format_wav.c.

References ast_filestream::_private, AST_FORMAT_SLINEAR16, check_header(), ast_filestream::f, ast_filestream::fmt, ast_format::format, and wav_desc::maxlen.

{
   /* We don't have any header to read or anything really, but
      if we did, it would go here.  We also might want to check
      and be sure it's a valid file.  */
   struct wav_desc *tmp = (struct wav_desc *)s->_private;
   if ((tmp->maxlen = check_header(s->f, (s->fmt->format == AST_FORMAT_SLINEAR16 ? 16000 : 8000))) < 0)
      return -1;
   return 0;
}

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

Definition at line 359 of file format_wav.c.

References ast_filestream::_private, AST_FORMAT_SLINEAR, AST_FORMAT_SLINEAR16, AST_FRAME_SET_BUFFER, AST_FRAME_VOICE, AST_FRIENDLY_OFFSET, ast_log(), ast_filestream::buf, ast_frame_subclass::codec, ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_filestream::fr, ast_frame::frametype, wav_desc::hz, LOG_WARNING, ast_frame::mallocd, wav_desc::maxlen, ast_frame::ptr, ast_frame::samples, ast_frame::subclass, and WAV_BUF_SIZE.

{
   int res;
   int samples;   /* actual samples read */
#if __BYTE_ORDER == __BIG_ENDIAN
   int x;
   short *tmp;
#endif
   int bytes;
   off_t here;
   /* Send a frame from the file to the appropriate channel */
   struct wav_desc *fs = (struct wav_desc *)s->_private;

   bytes = (fs->hz == 16000 ? (WAV_BUF_SIZE * 2) : WAV_BUF_SIZE);

   here = ftello(s->f);
   if (fs->maxlen - here < bytes)      /* truncate if necessary */
      bytes = fs->maxlen - here;
   if (bytes < 0)
      bytes = 0;
/*    ast_debug(1, "here: %d, maxlen: %d, bytes: %d\n", here, s->maxlen, bytes); */
   s->fr.frametype = AST_FRAME_VOICE;
   s->fr.subclass.codec = (fs->hz == 16000 ? AST_FORMAT_SLINEAR16 : AST_FORMAT_SLINEAR);
   s->fr.mallocd = 0;
   AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, bytes);
   
   if ( (res = fread(s->fr.data.ptr, 1, s->fr.datalen, s->f)) <= 0 ) {
      if (res)
         ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
      return NULL;
   }
   s->fr.datalen = res;
   s->fr.samples = samples = res / 2;

#if __BYTE_ORDER == __BIG_ENDIAN
   tmp = (short *)(s->fr.data.ptr);
   /* file format is little endian so we need to swap */
   for( x = 0; x < samples; x++)
      tmp[x] = (tmp[x] << 8) | ((tmp[x] & 0xff00) >> 8);
#endif

   *whennext = samples;
   return &s->fr;
}

static int wav_rewrite	(	struct ast_filestream *	s,
		const char *	comment
	)		`[static]`

Definition at line 325 of file format_wav.c.

References ast_filestream::_private, AST_FORMAT_SLINEAR16, ast_filestream::f, ast_filestream::fmt, ast_format::format, wav_desc::hz, and write_header().

{
   /* We don't have any header to read or anything really, but
      if we did, it would go here.  We also might want to check
      and be sure it's a valid file.  */

   struct wav_desc *tmp = (struct wav_desc *)s->_private;
   tmp->hz = (s->fmt->format == AST_FORMAT_SLINEAR16 ? 16000 : 8000);
   if (write_header(s->f,tmp->hz))
      return -1;
   return 0;
}

static int wav_seek	(	struct ast_filestream *	fs,
		off_t	sample_offset,
		int	whence
	)		`[static]`

Definition at line 453 of file format_wav.c.

References ast_filestream::f, and SEEK_FORCECUR.

{
   off_t min, max, cur, offset = 0, samples;

   samples = sample_offset * 2; /* SLINEAR is 16 bits mono, so sample_offset * 2 = bytes */
   min = 44; /* wav header is 44 bytes */
   cur = ftello(fs->f);
   fseeko(fs->f, 0, SEEK_END);
   max = ftello(fs->f);
   if (whence == SEEK_SET)
      offset = samples + min;
   else if (whence == SEEK_CUR || whence == SEEK_FORCECUR)
      offset = samples + cur;
   else if (whence == SEEK_END)
      offset = max - samples;
        if (whence != SEEK_FORCECUR) {
      offset = (offset > max)?max:offset;
   }
   /* always protect the header space. */
   offset = (offset < min)?min:offset;
   return fseeko(fs->f, offset, SEEK_SET);
}

static off_t wav_tell ( struct ast_filestream * fs ) [static]

Definition at line 483 of file format_wav.c.

References ast_filestream::f.

{
   off_t offset;
   offset = ftello(fs->f);
   /* subtract header size to get samples, then divide by 2 for 16 bit samples */
   return (offset - 44)/2;
}

static int wav_trunc ( struct ast_filestream * fs ) [static]

Definition at line 476 of file format_wav.c.

References ast_filestream::f, and update_header().

{
   if (ftruncate(fileno(fs->f), ftello(fs->f)))
      return -1;
   return update_header(fs->f);
}

static int wav_write	(	struct ast_filestream *	fs,
		struct ast_frame *	f
	)		`[static]`

Definition at line 404 of file format_wav.c.

References ast_filestream::_private, AST_FORMAT_SLINEAR, AST_FORMAT_SLINEAR16, AST_FRAME_VOICE, ast_getformatname(), ast_log(), wav_desc::bytes, ast_frame_subclass::codec, ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_filestream::fmt, ast_format::format, ast_frame::frametype, wav_desc::hz, LOG_WARNING, ast_frame::ptr, and ast_frame::subclass.

{
#if __BYTE_ORDER == __BIG_ENDIAN
   int x;
   short tmp[16000], *tmpi;
#endif
   struct wav_desc *s = (struct wav_desc *)fs->_private;
   int res;

   if (f->frametype != AST_FRAME_VOICE) {
      ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
      return -1;
   }
   if ((f->subclass.codec != AST_FORMAT_SLINEAR) && (f->subclass.codec != AST_FORMAT_SLINEAR16)) {
      ast_log(LOG_WARNING, "Asked to write non-SLINEAR%s frame (%s)!\n", s->hz == 16000 ? "16" : "", ast_getformatname(f->subclass.codec));
      return -1;
   }
   if (f->subclass.codec != fs->fmt->format) {
      ast_log(LOG_WARNING, "Can't change SLINEAR frequency during write\n");
      return -1;
   }
   if (!f->datalen)
      return -1;

#if __BYTE_ORDER == __BIG_ENDIAN
   /* swap and write */
   if (f->datalen > sizeof(tmp)) {
      ast_log(LOG_WARNING, "Data length is too long\n");
      return -1;
   }
   tmpi = f->data.ptr;
   for (x=0; x < f->datalen/2; x++) 
      tmp[x] = (tmpi[x] << 8) | ((tmpi[x] & 0xff00) >> 8);

   if ((res = fwrite(tmp, 1, f->datalen, fs->f)) != f->datalen ) {
#else
   /* just write */
   if ((res = fwrite(f->data.ptr, 1, f->datalen, fs->f)) != f->datalen ) {
#endif
      ast_log(LOG_WARNING, "Bad write (%d): %s\n", res, strerror(errno));
      return -1;
   }

   s->bytes += f->datalen;
      
   return 0;

}

static int write_header	(	FILE *	f,
		int	writehz
	)		`[static]`

Definition at line 243 of file format_wav.c.

References ast_log(), and LOG_WARNING.

Referenced by wav_rewrite().

{
   unsigned int hz;
   unsigned int bhz;
   unsigned int hs = htoll(16);
   unsigned short fmt = htols(1);
   unsigned short chans = htols(1);
   unsigned short bysam = htols(2);
   unsigned short bisam = htols(16);
   unsigned int size = htoll(0);

   if (writehz == 16000) {
      hz = htoll(16000);
      bhz = htoll(32000);
   } else {
      hz = htoll(8000);
      bhz = htoll(16000);
   }
   /* Write a wav header, ignoring sizes which will be filled in later */
   fseek(f,0,SEEK_SET);
   if (fwrite("RIFF", 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&size, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite("WAVEfmt ", 1, 8, f) != 8) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&hs, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&fmt, 1, 2, f) != 2) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&chans, 1, 2, f) != 2) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&hz, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&bhz, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&bysam, 1, 2, f) != 2) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&bisam, 1, 2, f) != 2) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite("data", 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   if (fwrite(&size, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Unable to write header\n");
      return -1;
   }
   return 0;
}

Variable Documentation

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Microsoft WAV/WAV16 format (8kHz/16kHz Signed Linear)" , .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_APP_DEPEND } [static]

Definition at line 541 of file format_wav.c.

struct ast_module_info* ast_module_info = &__mod_info [static]

Definition at line 541 of file format_wav.c.

struct ast_format wav16_f [static]

Definition at line 491 of file format_wav.c.

struct ast_format wav_f [static]

Definition at line 507 of file format_wav.c.

Asterisk developer's documentation

Data Structures

Defines

Functions

Variables

Detailed Description

Define Documentation

Function Documentation

Variable Documentation