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	htoll(b) (b)
#define	htols(b) (b)
#define	ltohl(b) (b)
#define	ltohs(b) (b)
#define	WAV_BUF_SIZE 320
Functions
static void	__reg_module (void)
static void	__unreg_module (void)
static int	check_header (FILE *f)
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)
Variables
static struct ast_module_info __MODULE_INFO_SECTION	__mod_info = { __MODULE_INFO_GLOBALS .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Microsoft WAV format (8000Hz Signed Linear)" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = 10, }
static struct ast_module_info *	ast_module_info = &__mod_info
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 48 of file format_wav.c.

#define htoll ( b ) (b)

Definition at line 51 of file format_wav.c.

Referenced by update_header(), and write_header().

#define htols ( b ) (b)

Definition at line 52 of file format_wav.c.

Referenced by write_header().

#define ltohl ( b ) (b)

Definition at line 53 of file format_wav.c.

Referenced by check_header().

#define ltohs ( b ) (b)

Definition at line 54 of file format_wav.c.

Referenced by check_header().

#define WAV_BUF_SIZE 320

Definition at line 39 of file format_wav.c.

Referenced by wav_read().

Function Documentation

static void __reg_module ( void ) [static]

Definition at line 502 of file format_wav.c.

static void __unreg_module ( void ) [static]

Definition at line 502 of file format_wav.c.

static int check_header ( FILE * f ) [static]

Definition at line 73 of file format_wav.c.

References ast_log(), buf, DEFAULT_SAMPLE_RATE, format, LOG_WARNING, ltohl, ltohs, and type.

Referenced by wav_open().

{
   int type, size, formtype;
   int fmt, hsize;
   short format, chans, bysam, bisam;
   int bysec;
   int freq;
   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;
   }
   if (fread(&fmt, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Read failed (fmt)\n");
      return -1;
   }
   if (memcmp(&fmt, "fmt ", 4)) {
      ast_log(LOG_WARNING, "Does not say fmt\n");
      return -1;
   }
   if (fread(&hsize, 1, 4, f) != 4) {
      ast_log(LOG_WARNING, "Read failed (formtype)\n");
      return -1;
   }
   if (ltohl(hsize) < 16) {
      ast_log(LOG_WARNING, "Unexpected header size %d\n", ltohl(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) != DEFAULT_SAMPLE_RATE) {
      ast_log(LOG_WARNING, "Unexpected frequency %d\n", ltohl(freq));
      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,ltohl(hsize)-16,SEEK_CUR) == -1 ) {
      ast_log(LOG_WARNING, "Failed to skip remaining header bytes: %d\n", ltohl(hsize)-16 );
      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 (data)\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 (data)\n");
         return -1;
       }
       data = ltohl(data);
       if(memcmp(buf, "data", 4) == 0 ) 
         break;
       if(memcmp(buf, "fact", 4) != 0 ) {
         ast_log(LOG_WARNING, "Unknown block - not fact or data\n");
         return -1;
       }
       if (fseek(f,data,SEEK_CUR) == -1 ) {
         ast_log(LOG_WARNING, "Failed to skip fact block: %d\n", 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 load_module ( void ) [static]

Definition at line 486 of file format_wav.c.

References ast_format_register, AST_MODULE_LOAD_FAILURE, and AST_MODULE_LOAD_SUCCESS.

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

static int unload_module ( void ) [static]

Definition at line 493 of file format_wav.c.

References ast_format_unregister(), and ast_format::name.

{
   return ast_format_unregister(wav_f.name);
}

static int update_header ( FILE * f ) [static]

Definition at line 201 of file format_wav.c.

References ast_log(), fwrite, htoll, 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 327 of file format_wav.c.

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

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

   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 305 of file format_wav.c.

References ast_filestream::_private, check_header(), ast_filestream::f, 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)) < 0)
      return -1;
   return 0;
}

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

Definition at line 344 of file format_wav.c.

References ast_filestream::_private, AST_FORMAT_SLINEAR, AST_FRAME_SET_BUFFER, AST_FRAME_VOICE, AST_FRIENDLY_OFFSET, ast_log(), ast_filestream::buf, ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_filestream::fr, ast_frame::frametype, 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;
#endif
   short *tmp;
   int bytes = WAV_BUF_SIZE;  /* in bytes */
   off_t here;
   /* Send a frame from the file to the appropriate channel */
   struct wav_desc *fs = (struct wav_desc *)s->_private;

   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 = 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;

   tmp = (short *)(s->fr.data.ptr);
#if __BYTE_ORDER == __BIG_ENDIAN
   /* 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 316 of file format_wav.c.

References ast_filestream::f, 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.  */

   if (write_header(s->f))
      return -1;
   return 0;
}

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

Definition at line 432 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 462 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 455 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 387 of file format_wav.c.

References ast_filestream::_private, AST_FORMAT_SLINEAR, AST_FRAME_VOICE, ast_log(), wav_desc::bytes, ast_frame::data, ast_frame::datalen, errno, ast_filestream::f, ast_frame::frametype, fwrite, LOG_WARNING, ast_frame::ptr, s, and ast_frame::subclass.

{
#if __BYTE_ORDER == __BIG_ENDIAN
   int x;
   short tmp[8000], *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 != AST_FORMAT_SLINEAR) {
      ast_log(LOG_WARNING, "Asked to write non-SLINEAR frame (%d)!\n", f->subclass);
      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 ) [static]

Definition at line 242 of file format_wav.c.

References ast_log(), fwrite, htoll, htols, and LOG_WARNING.

Referenced by wav_rewrite().

{
   unsigned int hz=htoll(8000);
   unsigned int bhz = htoll(16000);
   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);
   /* 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 __MODULE_INFO_SECTION __mod_info = { __MODULE_INFO_GLOBALS .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Microsoft WAV format (8000Hz Signed Linear)" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = 10, } [static]

Definition at line 502 of file format_wav.c.

struct ast_module_info* ast_module_info = &__mod_info [static]

Definition at line 502 of file format_wav.c.

struct ast_format wav_f [static]

Definition at line 470 of file format_wav.c.

Asterisk developer's documentation

format_wav.c File Reference
Module: Media File Formats

Data Structures

Defines

Functions

Variables

Detailed Description

Define Documentation

Function Documentation

Variable Documentation

Asterisk developer's documentation

format_wav.c File ReferenceModule: Media File Formats

Data Structures

Defines

Functions

Variables

Detailed Description

Define Documentation

Function Documentation

Variable Documentation

format_wav.c File Reference
Module: Media File Formats