efax-36/efax/efaxlib.c

84 uchar *runtocode ( ENCODER *e, short *runs, int nr, uchar *codes )
98     rlen = *runs++ ;
115 /* Pad/truncate run-length coded scan line 'runs' of 'nr' runs by 'pad'
116    pixels (truncate if negative).  Returns the new number of runs. */
118 int xpad ( short *runs, int nr, int pad )
121     while ( pad < 0 ) pad += ( nr <= 0 ? -pad : runs [ --nr ] ) ;
122     runs [ nr++ ] = pad ;
124     if ( nr & 1 ) runs [ nr - 1 ] += pad ;
125     else runs [ nr++ ] = pad ;
132    If necessary, zero-length runs are created to avoid copying.  Returns
135 int xshift ( short *runs, int nr, int s )
140       s += runs [ i ] ;
141       n -= runs [ i ] ;
142       runs [ i ] = 0 ;
147     runs [ i ] += s ;
219    run is white.  Returns number of runs coded.  */
221 int bittorun ( uchar *bits, int n, short *runs )
225   short *runs0 = runs ;
235   *runs = 0 ;
239       *(++runs) = *p++ ;		  /* new run */
241       *runs += *p++ ;			  /* continue run */
243       *(++runs) = *p++ ;
247   return runs - runs0 + 1  ;
254    not null.  Returns the number of runs in the result.  */
382    and store the runs in 'runs'.  The font is scaled so it
385    line width if not null.  Returns number of runs coded. */
389 	       short *runs, int *ppels )
411   nr = bittorun ( out, ( nc*cw + 7 )/8, runs ) ;
416     pels = xscale ( runs, nr, ( w * 256 ) / font->w ) ;
418   pels += xshift ( runs, nr, lmargin ) ;
451    runs.  If pointer pels is not null it is used to save pixel count.
452    Returns number of runs stored, EOF on RTC, or -2 on EOF or other
455 int readruns ( IFILE *f, short *runs, int *pels )
465   maxp = ( p = runs ) + MAXRUNS ;
497   n = p - runs - 1 ;
498   for ( p = q = runs ; n-- > 0 ; )
505   n = q - runs ;
562    number of runs in runs and line width in pels if not null.
566    read. Fax pages also end at RTC. Returns number of runs stored
569 int readline ( IFILE *f, short *runs, int *pels )
594 			runs, pels ) ;
604 	nr = bittorun ( bits, f->page->w/8, runs ) ;
610       nr = readruns ( f, runs, pels ) ;
618    	nr = bittorun ( bits, nb, runs ) ;
629     nr = xinvert ( runs, nr ) ;
1139   short runs [ MAXRUNS ] ;
1142   if ( readruns ( f, runs, &pels ) < 0 || pels ) /* skip first EOL */
1401    run is 4 bytes (255, count, byte, data count), so runs > 4 bytes
1403    compactly so are preferred over runs.
1511    copy of > 2 bytes, runs of > 4 or data >=127.  Otherwise the
1513    uncoded byte (l) before output of runs/copies.  */
1682 /* Convert array 'runs' of 'nr' run lengths into a bit map 'buf'. Returns
1685 int runtobit ( short *runs, int nr, uchar *buf )
1696     len = *runs++ ;
1920 /* Output scan line of nr runs no times to output file f. */
1922 void writeline ( OFILE *f, short *runs, int nr, int no )
1938       nb = runtobit ( runs, nr, buf ) ;
1959       p = runtocode ( &f->e, runs, nr, buf ) ;
2019   short runs [ MAXRUNS ] ;
2033     while ( ! err && ( nr = readline ( &f, runs, &pels ) ) >= 0 ) {
2035 	nb += runtobit ( runs, nr, font->buf+nb ) ;
2188     /* white and black runs */
2209 t4tab wtab [ ( 64 + 27 + 13 ) + 1 ] = {	/* runs of white */
2241 t4tab btab [ ( 64 + 27 + 13 ) + 1 ] = {	/* runs of black */