Mon Mar 31 07:40:46 2008

Asterisk developer's documentation


format_wav.c File Reference

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

#include "asterisk.h"
#include <unistd.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <sys/time.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include "asterisk/lock.h"
#include "asterisk/channel.h"
#include "asterisk/file.h"
#include "asterisk/logger.h"
#include "asterisk/sched.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 GAIN   0
#define htoll(b)   (b)
#define htols(b)   (b)
#define ltohl(b)   (b)
#define ltohs(b)   (b)
#define WAV_BUF_SIZE   320

Functions

 AST_MODULE_INFO_STANDARD (ASTERISK_GPL_KEY,"Microsoft WAV format (8000Hz Signed Linear)")
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_framewav_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_format wav_f


Detailed Description

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

Definition in file format_wav.c.


Define Documentation

#define BLOCKSIZE   160

Definition at line 61 of file format_wav.c.

#define GAIN   0

Definition at line 63 of file format_wav.c.

#define htoll (  )     (b)

Definition at line 67 of file format_wav.c.

#define htols (  )     (b)

Definition at line 68 of file format_wav.c.

#define ltohl (  )     (b)

Definition at line 69 of file format_wav.c.

#define ltohs (  )     (b)

Definition at line 70 of file format_wav.c.

#define WAV_BUF_SIZE   320

Definition at line 52 of file format_wav.c.

Referenced by wav_read().


Function Documentation

AST_MODULE_INFO_STANDARD ( ASTERISK_GPL_KEY  ,
"Microsoft WAV format (8000Hz Signed Linear)"   
)

static int check_header ( FILE *  f  )  [static]

Definition at line 89 of file format_wav.c.

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

00090 {
00091    int type, size, formtype;
00092    int fmt, hsize;
00093    short format, chans, bysam, bisam;
00094    int bysec;
00095    int freq;
00096    int data;
00097    if (fread(&type, 1, 4, f) != 4) {
00098       ast_log(LOG_WARNING, "Read failed (type)\n");
00099       return -1;
00100    }
00101    if (fread(&size, 1, 4, f) != 4) {
00102       ast_log(LOG_WARNING, "Read failed (size)\n");
00103       return -1;
00104    }
00105    size = ltohl(size);
00106    if (fread(&formtype, 1, 4, f) != 4) {
00107       ast_log(LOG_WARNING, "Read failed (formtype)\n");
00108       return -1;
00109    }
00110    if (memcmp(&type, "RIFF", 4)) {
00111       ast_log(LOG_WARNING, "Does not begin with RIFF\n");
00112       return -1;
00113    }
00114    if (memcmp(&formtype, "WAVE", 4)) {
00115       ast_log(LOG_WARNING, "Does not contain WAVE\n");
00116       return -1;
00117    }
00118    if (fread(&fmt, 1, 4, f) != 4) {
00119       ast_log(LOG_WARNING, "Read failed (fmt)\n");
00120       return -1;
00121    }
00122    if (memcmp(&fmt, "fmt ", 4)) {
00123       ast_log(LOG_WARNING, "Does not say fmt\n");
00124       return -1;
00125    }
00126    if (fread(&hsize, 1, 4, f) != 4) {
00127       ast_log(LOG_WARNING, "Read failed (formtype)\n");
00128       return -1;
00129    }
00130    if (ltohl(hsize) < 16) {
00131       ast_log(LOG_WARNING, "Unexpected header size %d\n", ltohl(hsize));
00132       return -1;
00133    }
00134    if (fread(&format, 1, 2, f) != 2) {
00135       ast_log(LOG_WARNING, "Read failed (format)\n");
00136       return -1;
00137    }
00138    if (ltohs(format) != 1) {
00139       ast_log(LOG_WARNING, "Not a wav file %d\n", ltohs(format));
00140       return -1;
00141    }
00142    if (fread(&chans, 1, 2, f) != 2) {
00143       ast_log(LOG_WARNING, "Read failed (format)\n");
00144       return -1;
00145    }
00146    if (ltohs(chans) != 1) {
00147       ast_log(LOG_WARNING, "Not in mono %d\n", ltohs(chans));
00148       return -1;
00149    }
00150    if (fread(&freq, 1, 4, f) != 4) {
00151       ast_log(LOG_WARNING, "Read failed (freq)\n");
00152       return -1;
00153    }
00154    if (ltohl(freq) != DEFAULT_SAMPLE_RATE) {
00155       ast_log(LOG_WARNING, "Unexpected freqency %d\n", ltohl(freq));
00156       return -1;
00157    }
00158    /* Ignore the byte frequency */
00159    if (fread(&bysec, 1, 4, f) != 4) {
00160       ast_log(LOG_WARNING, "Read failed (BYTES_PER_SECOND)\n");
00161       return -1;
00162    }
00163    /* Check bytes per sample */
00164    if (fread(&bysam, 1, 2, f) != 2) {
00165       ast_log(LOG_WARNING, "Read failed (BYTES_PER_SAMPLE)\n");
00166       return -1;
00167    }
00168    if (ltohs(bysam) != 2) {
00169       ast_log(LOG_WARNING, "Can only handle 16bits per sample: %d\n", ltohs(bysam));
00170       return -1;
00171    }
00172    if (fread(&bisam, 1, 2, f) != 2) {
00173       ast_log(LOG_WARNING, "Read failed (Bits Per Sample): %d\n", ltohs(bisam));
00174       return -1;
00175    }
00176    /* Skip any additional header */
00177    if (fseek(f,ltohl(hsize)-16,SEEK_CUR) == -1 ) {
00178       ast_log(LOG_WARNING, "Failed to skip remaining header bytes: %d\n", ltohl(hsize)-16 );
00179       return -1;
00180    }
00181    /* Skip any facts and get the first data block */
00182    for(;;)
00183    { 
00184       char buf[4];
00185        
00186        /* Begin data chunk */
00187        if (fread(&buf, 1, 4, f) != 4) {
00188          ast_log(LOG_WARNING, "Read failed (data)\n");
00189          return -1;
00190        }
00191        /* Data has the actual length of data in it */
00192        if (fread(&data, 1, 4, f) != 4) {
00193          ast_log(LOG_WARNING, "Read failed (data)\n");
00194          return -1;
00195        }
00196        data = ltohl(data);
00197        if(memcmp(buf, "data", 4) == 0 ) 
00198          break;
00199        if(memcmp(buf, "fact", 4) != 0 ) {
00200          ast_log(LOG_WARNING, "Unknown block - not fact or data\n");
00201          return -1;
00202        }
00203        if (fseek(f,data,SEEK_CUR) == -1 ) {
00204          ast_log(LOG_WARNING, "Failed to skip fact block: %d\n", data );
00205          return -1;
00206        }
00207    }
00208 #if 0
00209    curpos = lseek(fd, 0, SEEK_CUR);
00210    truelength = lseek(fd, 0, SEEK_END);
00211    lseek(fd, curpos, SEEK_SET);
00212    truelength -= curpos;
00213 #endif   
00214    return data;
00215 }

static int load_module ( void   )  [static]

Definition at line 491 of file format_wav.c.

References ast_format_register, and wav_f.

00492 {
00493    return ast_format_register(&wav_f);
00494 }

static int unload_module ( void   )  [static]

Definition at line 496 of file format_wav.c.

References ast_format_unregister(), ast_format::name, and wav_f.

00497 {
00498    return ast_format_unregister(wav_f.name);
00499 }  

static int update_header ( FILE *  f  )  [static]

Definition at line 217 of file format_wav.c.

References ast_log(), htoll, and LOG_WARNING.

00218 {
00219    off_t cur,end;
00220    int datalen,filelen,bytes;
00221    
00222    cur = ftello(f);
00223    fseek(f, 0, SEEK_END);
00224    end = ftello(f);
00225    /* data starts 44 bytes in */
00226    bytes = end - 44;
00227    datalen = htoll(bytes);
00228    /* chunk size is bytes of data plus 36 bytes of header */
00229    filelen = htoll(36 + bytes);
00230    
00231    if (cur < 0) {
00232       ast_log(LOG_WARNING, "Unable to find our position\n");
00233       return -1;
00234    }
00235    if (fseek(f, 4, SEEK_SET)) {
00236       ast_log(LOG_WARNING, "Unable to set our position\n");
00237       return -1;
00238    }
00239    if (fwrite(&filelen, 1, 4, f) != 4) {
00240       ast_log(LOG_WARNING, "Unable to set write file size\n");
00241       return -1;
00242    }
00243    if (fseek(f, 40, SEEK_SET)) {
00244       ast_log(LOG_WARNING, "Unable to set our position\n");
00245       return -1;
00246    }
00247    if (fwrite(&datalen, 1, 4, f) != 4) {
00248       ast_log(LOG_WARNING, "Unable to set write datalen\n");
00249       return -1;
00250    }
00251    if (fseeko(f, cur, SEEK_SET)) {
00252       ast_log(LOG_WARNING, "Unable to return to position\n");
00253       return -1;
00254    }
00255    return 0;
00256 }

static void wav_close ( struct ast_filestream s  )  [static]

Definition at line 343 of file format_wav.c.

References wav_desc::bytes, and s.

00344 {
00345    char zero = 0;
00346    struct wav_desc *fs = (struct wav_desc *)s->_private;
00347    /* Pad to even length */
00348    if (fs->bytes & 0x1)
00349       fwrite(&zero, 1, 1, s->f);
00350 }

static int wav_open ( struct ast_filestream s  )  [static]

Definition at line 321 of file format_wav.c.

References check_header(), wav_desc::maxlen, and s.

00322 {
00323    /* We don't have any header to read or anything really, but
00324       if we did, it would go here.  We also might want to check
00325       and be sure it's a valid file.  */
00326    struct wav_desc *tmp = (struct wav_desc *)s->_private;
00327    if ((tmp->maxlen = check_header(s->f)) < 0)
00328       return -1;
00329    return 0;
00330 }

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

Definition at line 352 of file format_wav.c.

References AST_FORMAT_SLINEAR, AST_FRAME_SET_BUFFER, AST_FRAME_VOICE, AST_FRIENDLY_OFFSET, ast_log(), errno, LOG_WARNING, wav_desc::maxlen, s, ast_frame::samples, and WAV_BUF_SIZE.

00353 {
00354    int res;
00355    int samples;   /* actual samples read */
00356    short *tmp;
00357    int bytes = WAV_BUF_SIZE;  /* in bytes */
00358    off_t here;
00359    /* Send a frame from the file to the appropriate channel */
00360    struct wav_desc *fs = (struct wav_desc *)s->_private;
00361 
00362    here = ftello(s->f);
00363    if (fs->maxlen - here < bytes)      /* truncate if necessary */
00364       bytes = fs->maxlen - here;
00365    if (bytes < 0)
00366       bytes = 0;
00367 /*    ast_log(LOG_DEBUG, "here: %d, maxlen: %d, bytes: %d\n", here, s->maxlen, bytes); */
00368    s->fr.frametype = AST_FRAME_VOICE;
00369    s->fr.subclass = AST_FORMAT_SLINEAR;
00370    s->fr.mallocd = 0;
00371    AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, bytes);
00372    
00373    if ( (res = fread(s->fr.data, 1, s->fr.datalen, s->f)) <= 0 ) {
00374       if (res)
00375          ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
00376       return NULL;
00377    }
00378    s->fr.datalen = res;
00379    s->fr.samples = samples = res / 2;
00380 
00381    tmp = (short *)(s->fr.data);
00382 #if __BYTE_ORDER == __BIG_ENDIAN
00383    /* file format is little endian so we need to swap */
00384    for( x = 0; x < samples; x++)
00385       tmp[x] = (tmp[x] << 8) | ((tmp[x] & 0xff00) >> 8);
00386 #endif
00387    *whennext = samples;
00388    return &s->fr;
00389 }

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

Definition at line 332 of file format_wav.c.

References s, and write_header().

00333 {
00334    /* We don't have any header to read or anything really, but
00335       if we did, it would go here.  We also might want to check
00336       and be sure it's a valid file.  */
00337 
00338    if (write_header(s->f))
00339       return -1;
00340    return 0;
00341 }

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

Definition at line 437 of file format_wav.c.

References ast_filestream::f, offset, and SEEK_FORCECUR.

00438 {
00439    off_t min, max, cur, offset = 0, samples;
00440 
00441    samples = sample_offset * 2; /* SLINEAR is 16 bits mono, so sample_offset * 2 = bytes */
00442    min = 44; /* wav header is 44 bytes */
00443    cur = ftello(fs->f);
00444    fseeko(fs->f, 0, SEEK_END);
00445    max = ftello(fs->f);
00446    if (whence == SEEK_SET)
00447       offset = samples + min;
00448    else if (whence == SEEK_CUR || whence == SEEK_FORCECUR)
00449       offset = samples + cur;
00450    else if (whence == SEEK_END)
00451       offset = max - samples;
00452         if (whence != SEEK_FORCECUR) {
00453       offset = (offset > max)?max:offset;
00454    }
00455    /* always protect the header space. */
00456    offset = (offset < min)?min:offset;
00457    return fseeko(fs->f, offset, SEEK_SET);
00458 }

static off_t wav_tell ( struct ast_filestream fs  )  [static]

Definition at line 467 of file format_wav.c.

References ast_filestream::f, and offset.

00468 {
00469    off_t offset;
00470    offset = ftello(fs->f);
00471    /* subtract header size to get samples, then divide by 2 for 16 bit samples */
00472    return (offset - 44)/2;
00473 }

static int wav_trunc ( struct ast_filestream fs  )  [static]

Definition at line 460 of file format_wav.c.

References ast_filestream::f, and update_header().

00461 {
00462    if (ftruncate(fileno(fs->f), ftello(fs->f)))
00463       return -1;
00464    return update_header(fs->f);
00465 }

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

Definition at line 391 of file format_wav.c.

References ast_filestream::_private, AST_FORMAT_SLINEAR, AST_FRAME_VOICE, ast_log(), errno, ast_filestream::f, f, LOG_WARNING, and s.

00392 {
00393    int x;
00394    short tmp[8000], *tmpi;
00395    struct wav_desc *s = (struct wav_desc *)fs->_private;
00396    int res;
00397 
00398    if (f->frametype != AST_FRAME_VOICE) {
00399       ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
00400       return -1;
00401    }
00402    if (f->subclass != AST_FORMAT_SLINEAR) {
00403       ast_log(LOG_WARNING, "Asked to write non-SLINEAR frame (%d)!\n", f->subclass);
00404       return -1;
00405    }
00406    if (f->datalen > sizeof(tmp)) {
00407       ast_log(LOG_WARNING, "Data length is too long\n");
00408       return -1;
00409    }
00410    if (!f->datalen)
00411       return -1;
00412 
00413 #if 0
00414    printf("Data Length: %d\n", f->datalen);
00415 #endif   
00416 
00417    tmpi = f->data;
00418    /* Volume adjust here to accomodate */
00419    for (x=0;x<f->datalen/2;x++) {
00420       tmp[x] = tmpi[x];
00421 #if __BYTE_ORDER == __BIG_ENDIAN
00422       tmp[x] = (tmp[x] << 8) | ((tmp[x] & 0xff00) >> 8);
00423 #endif
00424    }
00425    if ((res = fwrite(tmp, 1, f->datalen, fs->f)) != f->datalen ) {
00426       ast_log(LOG_WARNING, "Bad write (%d): %s\n", res, strerror(errno));
00427       return -1;
00428    }
00429 
00430    s->bytes += f->datalen;
00431    update_header(fs->f);
00432       
00433    return 0;
00434 
00435 }

static int write_header ( FILE *  f  )  [static]

Definition at line 258 of file format_wav.c.

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

00259 {
00260    unsigned int hz=htoll(8000);
00261    unsigned int bhz = htoll(16000);
00262    unsigned int hs = htoll(16);
00263    unsigned short fmt = htols(1);
00264    unsigned short chans = htols(1);
00265    unsigned short bysam = htols(2);
00266    unsigned short bisam = htols(16);
00267    unsigned int size = htoll(0);
00268    /* Write a wav header, ignoring sizes which will be filled in later */
00269    fseek(f,0,SEEK_SET);
00270    if (fwrite("RIFF", 1, 4, f) != 4) {
00271       ast_log(LOG_WARNING, "Unable to write header\n");
00272       return -1;
00273    }
00274    if (fwrite(&size, 1, 4, f) != 4) {
00275       ast_log(LOG_WARNING, "Unable to write header\n");
00276       return -1;
00277    }
00278    if (fwrite("WAVEfmt ", 1, 8, f) != 8) {
00279       ast_log(LOG_WARNING, "Unable to write header\n");
00280       return -1;
00281    }
00282    if (fwrite(&hs, 1, 4, f) != 4) {
00283       ast_log(LOG_WARNING, "Unable to write header\n");
00284       return -1;
00285    }
00286    if (fwrite(&fmt, 1, 2, f) != 2) {
00287       ast_log(LOG_WARNING, "Unable to write header\n");
00288       return -1;
00289    }
00290    if (fwrite(&chans, 1, 2, f) != 2) {
00291       ast_log(LOG_WARNING, "Unable to write header\n");
00292       return -1;
00293    }
00294    if (fwrite(&hz, 1, 4, f) != 4) {
00295       ast_log(LOG_WARNING, "Unable to write header\n");
00296       return -1;
00297    }
00298    if (fwrite(&bhz, 1, 4, f) != 4) {
00299       ast_log(LOG_WARNING, "Unable to write header\n");
00300       return -1;
00301    }
00302    if (fwrite(&bysam, 1, 2, f) != 2) {
00303       ast_log(LOG_WARNING, "Unable to write header\n");
00304       return -1;
00305    }
00306    if (fwrite(&bisam, 1, 2, f) != 2) {
00307       ast_log(LOG_WARNING, "Unable to write header\n");
00308       return -1;
00309    }
00310    if (fwrite("data", 1, 4, f) != 4) {
00311       ast_log(LOG_WARNING, "Unable to write header\n");
00312       return -1;
00313    }
00314    if (fwrite(&size, 1, 4, f) != 4) {
00315       ast_log(LOG_WARNING, "Unable to write header\n");
00316       return -1;
00317    }
00318    return 0;
00319 }


Variable Documentation

struct ast_format wav_f [static]

Definition at line 475 of file format_wav.c.

Referenced by load_module(), and unload_module().


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