tomwalters@0: /*
tomwalters@0:  ftgram.c       Row-wise fft program by Michael Allerhand.
tomwalters@0: ----------
tomwalters@0: 
tomwalters@0:   Short-time Fourier transform applied to each row of input frames.
tomwalters@0:   Output frames consist of row-wise magnitude spectra, computed using fft.
tomwalters@0: 
tomwalters@0: Input/output:
tomwalters@0:   Read a header and frame in NAP format.
tomwalters@0:   Write a header, (constructed from the original input header), and a
tomwalters@0:   succession of frames in SAI format.
tomwalters@0: 
tomwalters@0:   The input file is interpreted as one large frame in NAP format to be
tomwalters@0:   divided into input frames, each to be processed and output in SAI format.
tomwalters@0: 
tomwalters@0:   The options "start" and "length" specify the input file.
tomwalters@0:   The special option value length=max specifies all the input file from
tomwalters@0:   the given start to its end.
tomwalters@0: 
tomwalters@0:   The options "width" and "frstep"  specify the input frames.
tomwalters@0:   The width option is the framewidth of each input frame) and the frstep
tomwalters@0:   option is the frameshift between input frames in the input file.
tomwalters@0:   The special option value width=max specifies the input framewidth as equal
tomwalters@0:   to the given input file length, (and if this is also "max", then the
tomwalters@0:   input framewidth is the remainder of the input file).
tomwalters@0: 
tomwalters@0:   Most options in the input header are copied to the output header.
tomwalters@0:   This enables options which are needed for the eventual display
tomwalters@0:   to pass straight through. Some options are set so that they can override
tomwalters@0:   the input header. For example, the display option is set on to enable
tomwalters@0:   display even when input has display=off. The animate option can be set on
tomwalters@0:   even when the input has animate=off.
tomwalters@0:   Parts of the header are changed for the new sai format:
tomwalters@0:   (frames, frameshift, framewidth, frameheight, framebytes).
tomwalters@0: 
tomwalters@0: Padding:
tomwalters@0:   The output framewidth is the next power-of-2 above twice the input
tomwalters@0:   framewidth.
tomwalters@0:   The rows of each input frame are padded with zeroes so that the input
tomwalters@0:   framewidth is at least twice its original size, and also a power of 2.
tomwalters@0:   This is because the fft method is "radix-2", and because each output
tomwalters@0:   spectrum is symmetrical so that just half the points are unique.
tomwalters@0:   It is advisable to pad input frames for the additional reason that
tomwalters@0:   padding counters frame end-effects.
tomwalters@0: 
tomwalters@0:   Therefore each row of each input frame is padded with zeroes to the next
tomwalters@0:   power of 2 larger than the original input framewidth.
tomwalters@0:   If necessary, extra padding can be enforced using the padding option to
tomwalters@0:   add extra zeroes, padding to a larger power of 2.
tomwalters@0:   The amount of extra padding is "exponential" since if the basic padded
tomwalters@0:   framesize is N, and the padding option is n, then extra padding is to:
tomwalters@0:   N * 2**n.
tomwalters@0:   (n=0 by default, so that N is not changed. When n=1 then N is doubled, and
tomwalters@0:   when n=2 then N is quadrupled, etc.).
tomwalters@0: 
tomwalters@0:   The output framewidth (and hence the frequency resolution) depends upon the
tomwalters@0:   input framewidth and the padding.
tomwalters@0: 
tomwalters@0: Examples:
tomwalters@0: 
tomwalters@0: 1. ftgram of a NAP, animated, with framewidth 16ms
tomwalters@0: 
tomwalters@0: gennap len=128ms output=stdout display=off file | ftgram width=16ms anim=on > file.sai
tomwalters@0: gensai useprev=on headr=5 top=1000 file             -(for landscape plot)
tomwalters@0: genspl useprev=on headr=5 top=1000 pensize=2 file   -(for spiral plot)
tomwalters@0: 
tomwalters@0: 2. ftgram of an SAI:
tomwalters@0:   (Note that gensai removes file.sai, so you must use some other name, eg foo.sai).
tomwalters@0: 
tomwalters@0: gensai len=64 pwidth=64 nwidth=0 output=stdout display=off file |  \
tomwalters@0: saitonap frame=3 | ftgram width=32ms frame=1 > foo.sai
tomwalters@0: gensai useprev=on top=1000 headr=5 mag=2 foo
tomwalters@0: 
tomwalters@0: 
tomwalters@0: */
tomwalters@0: 
tomwalters@0: #include <stdio.h>
tomwalters@0: #include <math.h>
tomwalters@0: #include "header.h"
tomwalters@0: #include "options.h"
tomwalters@0: #include "units.h"
tomwalters@0: #include "strmatch.h"
tomwalters@0: #include "sigproc.h"
tomwalters@0: 
tomwalters@0: char applic[]     = "Autocorrelogram auditory image." ;
tomwalters@0: 
tomwalters@0: static char *helpstr  , *debugstr, *dispstr , *anistr   , *startstr  ;
tomwalters@0: static char *lengthstr, *widthstr, *shiftstr, *headerstr, *framestr  ;
tomwalters@0: static char *wstr     , *scalestr, *padstr                           ;
tomwalters@0: 
tomwalters@0: static Options option[] = {
tomwalters@0:     {   "help"      ,   "off"       ,  &helpstr     ,   "help"                                       , DEBUG   },
tomwalters@0:     {   "debug"     ,   "off"       ,  &debugstr    ,   "debugging switch"                           , DEBUG   },
tomwalters@0:     {   "display"   ,   "on"        ,  &dispstr     ,   "Display output image."                      , SETFLAG },
tomwalters@0:     {   "animate"   ,   "off"       ,  &anistr      ,   "Animate cartoon."                           , SETFLAG },
tomwalters@0:     {   "frames"    ,   "1-max"     ,  &framestr    ,   "Select frames inclusively"                  , VAL     },
tomwalters@0:     {   "header"    ,   "on"        ,  &headerstr   ,   "Header (for gensai useprevious=on)."        , VAL     },
tomwalters@0:     {   "start"     ,   "0"         ,  &startstr    ,   "Start point in i/p file."                   , VAL     },
tomwalters@0:     {   "length"    ,   "max"       ,  &lengthstr   ,   "Length of i/p file to process."             , VAL     },
tomwalters@0:     {   "frstep"    ,   "16ms"      ,  &shiftstr    ,   "Step between input frames."                 , VAL     },
tomwalters@0:     {   "width"     ,   "32ms"      ,  &widthstr    ,   "Width of input frames."                     , VAL     },
tomwalters@0:     {   "padding"   ,   "0"         ,  &padstr      ,   "Exponential frame padding"                  , SVAL    },
tomwalters@0:     {   "window"    ,   "on"        ,  &wstr        ,   "Hamming window"                             , SETFLAG },
tomwalters@0:     {   "scale"     ,   "0.08"      ,  &scalestr    ,   "Scale factor for output"                    , SVAL    },
tomwalters@0:    ( char * ) 0 } ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0: int     samplerate ;
tomwalters@0: 
tomwalters@0: int     frameheight, framewidth ;
tomwalters@0: int     frames, framebytes ;
tomwalters@0: int     frameshift ;
tomwalters@0: 
tomwalters@0: int     Newframeheight, Newframewidth ;
tomwalters@0: int     Newframes, Newframebytes ;
tomwalters@0: int     Newframeshift ;
tomwalters@0: 
tomwalters@0: int     start, length ; /* Size of input file (num cols) */
tomwalters@0: int     frameslength ;  /* Length (num cols) of input file to process */
tomwalters@0: 
tomwalters@0: int     zeroes ;
tomwalters@0: int     window ;        /* Flag for Hamming window */
tomwalters@0: float   scale  ;        /* Scale factor for output */
tomwalters@0: 
tomwalters@0: short  *file ;          /* Input file (NAP format) */
tomwalters@0: float  *W    ;          /* Hamming window for fft  */
tomwalters@0: float  *buf  ;          /* fft working space       */
tomwalters@0: 
tomwalters@0: 
tomwalters@0: main(argc, argv)
tomwalters@0: int   argc ;
tomwalters@0: char *argv[] ;
tomwalters@0: {
tomwalters@0:     FILE   *fp ;
tomwalters@0:     char   *header, *SaiHeader();
tomwalters@0:     char   *versionstr, c ;
tomwalters@0:     int     startbytes, framebyteshift ;
tomwalters@0:     short  *frame, *endframe ;
tomwalters@0:     int     i, a, b ;
tomwalters@0: 
tomwalters@0:     fp = openopts( option,argc,argv ) ;
tomwalters@0:     if ( !isoff( helpstr ) )
tomwalters@0: 	helpopts( helpstr, argv[0], applic, option ) ;
tomwalters@0: 
tomwalters@0:     window  = ison( wstr ) ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** parse bounds on number of frames ****/
tomwalters@0: 
tomwalters@0:     if ( selector( framestr, &a, &b ) == 0 ) {
tomwalters@0: 	fprintf(stderr,"ftgram: bad frame selector [%s]\n", framestr ) ;
tomwalters@0: 	exit( 1 ) ;
tomwalters@0:     }
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Input frame dimensions (from header and options) ****/
tomwalters@0: 
tomwalters@0:     if ((header = ReadHeader(fp)) == (char *) 0 ) {
tomwalters@0: 	fprintf(stderr,"ftgram: header not found\n");
tomwalters@0: 	exit(1);
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     if ( (versionstr = HeaderString( header, "Version" )) == (char *)0 ) {
tomwalters@0: 	fprintf(stderr,"ftgram: model version-number not found in header\n");
tomwalters@0: 	exit(1);
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     samplerate  = HeaderSamplerate( header );
tomwalters@0: 
tomwalters@0:     /* In NAP format, the size of the 2-D image is given by:  */
tomwalters@0:     /*   frameheight = number of rows (filterbank channels)   */
tomwalters@0:     /*   frames      = number of columns (sample points)      */
tomwalters@0: 
tomwalters@0:     frameheight = HeaderInt( header, "frameheight" );
tomwalters@0:     frames      = HeaderInt( header, "frames"      );
tomwalters@0: 
tomwalters@0:     if ( ( frameshift  = to_p( shiftstr, samplerate ) ) <= 0 ) {
tomwalters@0: 	fprintf(stderr,"ftgram: non-positive frstep [%d]\n", frameshift);
tomwalters@0: 	exit(1);
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     /* calculate start of first frame (in cols) */
tomwalters@0: 
tomwalters@0:     if ( ( start = to_p( startstr, samplerate ) + ( a-1 ) * frameshift ) >= frames ) {
tomwalters@0: 	fprintf(stderr,"ftgram: input file too small (%dms) for given framing parameters\n", frames * 1000 / samplerate );
tomwalters@0: 	exit(1);
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     /* get length of input file (in cols) and framewidth of input frames */
tomwalters@0: 
tomwalters@0:     if ( ismax( lengthstr ) ) length = frames - start ;
tomwalters@0:     else                      length = to_p( lengthstr, samplerate ) - start ;
tomwalters@0: 
tomwalters@0:     if ( ismax( widthstr ) )  framewidth = length ;
tomwalters@0:     else                      framewidth = to_p( widthstr, samplerate ) ;
tomwalters@0: 
tomwalters@0:     if ( length < framewidth ) {
tomwalters@0: 	fprintf(stderr,"ftgram: input file too small (%dms) for given framing parameters\n", frames * 1000 / samplerate );
tomwalters@0: 	exit(1);
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     /* calculate length (num cols) to process, and the number of frames */
tomwalters@0: 
tomwalters@0:     if ( b==0 ) {
tomwalters@0: 	frameslength = length ;
tomwalters@0: 	Newframes = 1 + ( length - framewidth ) / frameshift ;
tomwalters@0:     }
tomwalters@0:     else {
tomwalters@0: 	frameslength = framewidth + ( b-a ) * frameshift ;
tomwalters@0: 	Newframes = b - ( a-1 ) ;
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     if ( start + frameslength > frames ) {
tomwalters@0: 	fprintf(stderr,"ftgram: input file too small (%dms) for requested start and length \n", frames * 1000 / samplerate );
tomwalters@0: 	exit(1);
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     framebytes = frameheight * frameslength * sizeof(short) ;
tomwalters@0:     startbytes = frameheight * start  * sizeof(short) ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Output frame dimensions ****/
tomwalters@0: 
tomwalters@0:     Newframeheight =  frameheight ;
tomwalters@0:     Newframewidth  =  ( framewidth + zeroes ) >> 1 ;  /* spectral bins */
tomwalters@0:     Newframeshift  =  frameshift ;
tomwalters@0:     Newframebytes  =  Newframeheight * Newframewidth * sizeof(short) ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Padding and output scale factor ****/
tomwalters@0: 
tomwalters@0:     zeroes = ( getpower( framewidth << 1 ) << atoi( padstr ) ) - framewidth ;
tomwalters@0:     scale  = atof( scalestr ) ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Debug ****/
tomwalters@0: 
tomwalters@0:     if ( ison( debugstr ) ) {
tomwalters@0: 	fprintf(stderr, "Input:   frames=%d frameheight=%d frameshift=%d\n", frames, frameheight, frameshift ) ;
tomwalters@0: 	fprintf(stderr, "Sizes:   start=%d length=%d framewidth=%d frameslength=%d\n", start, length, framewidth, frameslength ) ;
tomwalters@0: 	fprintf(stderr, "Output:  zeroes=%d Newframewidth=%d Newframes=%d \n", zeroes, Newframewidth, Newframes ) ;
tomwalters@0: 	exit( 1 ) ;
tomwalters@0:     }
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Allocate space (input file, window coeffs, and fft working space) ****/
tomwalters@0: 
tomwalters@0:     if ( ( file = (short *)malloc( framebytes ) ) == NULL ) {
tomwalters@0: 	fprintf(stderr,"ftgram: malloc out of space\n");
tomwalters@0: 	exit(1);
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     if ( window )
tomwalters@0: 	W = hamming( framewidth ) ;
tomwalters@0: 
tomwalters@0:     buf = (float *)malloc( ( framewidth + zeroes ) * sizeof(float) );
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Write new sai header ****/
tomwalters@0: 
tomwalters@0:     if ( ison( headerstr ) )
tomwalters@0: 	WriteHeader( SaiHeader(header), stdout );
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Seek to start of input file in blocks of framebytes ****/
tomwalters@0: 
tomwalters@0:     for (i=framebytes ; i < startbytes ; i += framebytes)
tomwalters@0: 	if ( fread( file, framebytes, 1, fp ) == NULL ) {
tomwalters@0: 	    fprintf(stderr,"ftgram: missing data after header\n");
tomwalters@0: 	    exit(1);
tomwalters@0: 	}
tomwalters@0:     if ( (startbytes -= (i - framebytes)) > 0 )
tomwalters@0: 	if ( fread( file, startbytes, 1, fp ) == NULL ) {
tomwalters@0: 	    fprintf(stderr,"ftgram: missing data after header\n");
tomwalters@0: 	    exit(1);
tomwalters@0: 	}
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Read framebytes of i/p file ****/
tomwalters@0: 
tomwalters@0:     if ( fread( file, framebytes, 1, fp ) == NULL ) {
tomwalters@0: 	fprintf(stderr,"ftgram: missing data after header\n");
tomwalters@0: 	exit(1);
tomwalters@0:     }
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /**** Process frames ****/
tomwalters@0: 
tomwalters@0:     framebyteshift = frameshift * frameheight ;
tomwalters@0:     endframe = file + Newframes * framebyteshift ;
tomwalters@0: 
tomwalters@0:     for ( frame = file, i=1 ; frame < endframe ; frame += framebyteshift, i++ ) {
tomwalters@0: 	fprintf(stderr,"ftgram: %d / %d  [%dms]\n", i, Newframes, start*1000/samplerate );
tomwalters@0: 	ftgram( frame ) ;
tomwalters@0: 	start += frameshift ;
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     fclose(fp);
tomwalters@0:     fprintf(stderr,"ftgram: done\n" ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: 
tomwalters@0: 
tomwalters@0: /********************************** FFT ************************************/
tomwalters@0: 
tomwalters@0: /* Call fft and magnitude spectrum for each row in auditory image */
tomwalters@0: 
tomwalters@0: ftgram( frame )
tomwalters@0: short *frame ;
tomwalters@0: {
tomwalters@0:     register int  i, j, row, col ;
tomwalters@0: 
tomwalters@0:     for ( row=0 ; row < frameheight ; row++ ) {
tomwalters@0: 
tomwalters@0: 	if ( window )
tomwalters@0: 	    for ( col=0 , i=row ; col < framewidth ; col++, i+=frameheight )
tomwalters@0: 		buf[col] = frame[i] * W[col] ;
tomwalters@0: 	else
tomwalters@0: 	    for ( col=0 , i=row ; col < framewidth ; col++, i+=frameheight )
tomwalters@0: 		buf[col] = frame[i] ;
tomwalters@0: 
tomwalters@0: 	for ( j=0 ; j<zeroes ; j++ )    /* padding */
tomwalters@0: 	    buf[col++] = 0 ;
tomwalters@0: 
tomwalters@0: 	fft( buf, framewidth+zeroes, 1 ) ;
tomwalters@0: 	mag( buf, framewidth+zeroes ) ;
tomwalters@0: 
tomwalters@0: 	writebuf( buf, Newframewidth, scale ) ;
tomwalters@0:     }
tomwalters@0: }
tomwalters@0: 
tomwalters@0: 
tomwalters@0: /********************** Write o/p ****************************************/
tomwalters@0: 
tomwalters@0: writebuf( buf, n, scale )       /* write buffer as scaled shorts */
tomwalters@0: float *buf ;
tomwalters@0: int    n ;
tomwalters@0: float  scale ;
tomwalters@0: {
tomwalters@0:     register int  i ;
tomwalters@0:     short         p ;
tomwalters@0: 
tomwalters@0:     for (i=0 ; i < n ; i++)  {
tomwalters@0: 	p = (short)( buf[i] * scale ) ;
tomwalters@0: 	fwrite( &p, sizeof(short), 1, stdout ) ;
tomwalters@0:     }
tomwalters@0: }
tomwalters@0: 
tomwalters@0: 
tomwalters@0: /************************ Output header ************************************/
tomwalters@0: /*
tomwalters@0:    Copy the original nap header to a new sai header, changing in order:
tomwalters@0:      frames
tomwalters@0:      frameshift
tomwalters@0:      framewidth
tomwalters@0:      frameheight
tomwalters@0:      framebytes
tomwalters@0:      animate
tomwalters@0:      display
tomwalters@0:    Finally, update the new header_bytes, and return the new header.
tomwalters@0: */
tomwalters@0: 
tomwalters@0: char *SaiHeader( napheader )
tomwalters@0: char *napheader ;
tomwalters@0: {
tomwalters@0:     char *saiheader;
tomwalters@0:     char *p0, *p1, *p2, *s, str[64];
tomwalters@0: 
tomwalters@0:     saiheader = (char *)malloc( strlen(napheader) + 64 ) ;
tomwalters@0: 
tomwalters@0:     p0 = saiheader ;
tomwalters@0:     p1 = napheader ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** copy up to frames **/
tomwalters@0: 
tomwalters@0:     p2 = HeaderString( napheader , "frames" ) ;
tomwalters@0:     while( p1 < p2 )
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0:     sprintf(str,"%d\n", Newframes);
tomwalters@0:     for (s = str ; *s != '\n' ; )
tomwalters@0: 	*p0++ = *s++;
tomwalters@0:     *p0++ = *s;
tomwalters@0:     while (*p1 != '\n')
tomwalters@0: 	*p1++;
tomwalters@0:     *p1++;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** copy up to frameshift **/
tomwalters@0: 
tomwalters@0:     p2 = HeaderString( napheader , "frameshift" ) ;
tomwalters@0:     while ( p1 < p2 )
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0:     sprintf(str,"%d\n", Newframeshift);
tomwalters@0:     for (s = str ; *s != '\n' ; )
tomwalters@0: 	*p0++ = *s++;
tomwalters@0:     *p0++ = *s;
tomwalters@0:     while (*p1 != '\n')
tomwalters@0: 	*p1++;
tomwalters@0:     *p1++;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** copy up to framewidth **/
tomwalters@0: 
tomwalters@0:     p2 = HeaderString( napheader , "framewidth" ) ;
tomwalters@0:     while ( p1 < p2 )
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0:     sprintf(str,"%d\n", Newframewidth);
tomwalters@0:     for (s = str ; *s != '\n' ; )
tomwalters@0: 	*p0++ = *s++;
tomwalters@0:     *p0++ = *s;
tomwalters@0:     while (*p1 != '\n')
tomwalters@0: 	*p1++;
tomwalters@0:     *p1++;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** copy up to frameheight **/
tomwalters@0: 
tomwalters@0:     p2 = HeaderString( napheader , "frameheight" ) ;
tomwalters@0:     while ( p1 < p2 )
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0:     sprintf(str,"%d\n", Newframeheight);
tomwalters@0:     for (s = str ; *s != '\n' ; )
tomwalters@0: 	*p0++ = *s++;
tomwalters@0:     *p0++ = *s;
tomwalters@0:     while (*p1 != '\n')
tomwalters@0: 	*p1++;
tomwalters@0:     *p1++;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** copy up to framebytes **/
tomwalters@0: 
tomwalters@0:     p2 = HeaderString( napheader , "framebytes" ) ;
tomwalters@0:     while ( p1 < p2 )
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0:     sprintf(str,"%d\n", Newframebytes);
tomwalters@0:     for (s = str ; *s != '\n' ; )
tomwalters@0: 	*p0++ = *s++;
tomwalters@0:     *p0++ = *s;
tomwalters@0:     while (*p1 != '\n')
tomwalters@0: 	*p1++;
tomwalters@0:     *p1++;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** copy up to animate_ctn **/
tomwalters@0: 
tomwalters@0:     p2 = HeaderString( napheader , "animate_ctn" ) ;
tomwalters@0:     while ( p1 < p2 )
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0:     sprintf(str,"%s\n", anistr );
tomwalters@0:     for (s = str ; *s != '\n' ; )
tomwalters@0: 	*p0++ = *s++;
tomwalters@0:     *p0++ = *s;
tomwalters@0:     while (*p1 != '\n')
tomwalters@0: 	*p1++;
tomwalters@0:     *p1++;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** copy up to display **/
tomwalters@0: 
tomwalters@0:     p2 = HeaderString( napheader , "display" ) ;
tomwalters@0:     while ( p1 < p2 )
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0:     sprintf(str,"%s\n", dispstr );
tomwalters@0:     for (s = str ; *s != '\n' ; )
tomwalters@0: 	*p0++ = *s++;
tomwalters@0:     *p0++ = *s;
tomwalters@0:     while (*p1 != '\n')
tomwalters@0: 	*p1++;
tomwalters@0:     *p1++;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** copy rest of header **/
tomwalters@0: 
tomwalters@0:     p2 = HeaderString( napheader , "Version" ) ;
tomwalters@0:     while ( p1 < p2 )
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0:     while (*p1 != '\n')
tomwalters@0: 	*p0++ = *p1++ ;
tomwalters@0:     *p0++ = *p1++ ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     /** update header_bytes **/
tomwalters@0: 
tomwalters@0:     sprintf(str, "%0*d", 7, p0-saiheader);
tomwalters@0:     p0 = HeaderString( saiheader , "header_bytes" ) ;
tomwalters@0:     s = str;
tomwalters@0:     while(*p0 != '\n')
tomwalters@0: 	*p0++ = *s++ ;
tomwalters@0: 
tomwalters@0: 
tomwalters@0:     return saiheader;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: