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#ifndef lint
static char rcsid[] = "$Header: /usr/people/sam/tiff/libtiff/RCS/tif_next.c,v 1.18 92/10/21 16:36:23 sam Exp $";
#endif
/*
* Copyright (c) 1988, 1989, 1990, 1991, 1992 Sam Leffler
* Copyright (c) 1991, 1992 Silicon Graphics, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software and
* its documentation for any purpose is hereby granted without fee, provided
* that (i) the above copyright notices and this permission notice appear in
* all copies of the software and related documentation, and (ii) the names of
* Sam Leffler and Silicon Graphics may not be used in any advertising or
* publicity relating to the software without the specific, prior written
* permission of Sam Leffler and Silicon Graphics.
*
* THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
* EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
* WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
*
* IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
* WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
* LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
/*
* TIFF Library.
*
* NeXT 2-bit Grey Scale Compression Algorithm Support
*/
#include "tiffiop.h"
#define SETPIXEL(op, v) { \
switch (npixels++ & 3) { \
case 0: op[0] = (v) << 6; break; \
case 1: op[0] |= (v) << 4; break; \
case 2: op[0] |= (v) << 2; break; \
case 3: *op++ |= (v); break; \
} \
}
#define LITERALROW 0x00
#define LITERALSPAN 0x40
#define WHITE ((1<<2)-1)
static int
DECLARE4(NeXTDecode, TIFF*, tif, u_char*, buf, u_long, occ, u_int, s)
{
register u_char *bp, *op;
register int cc, n;
u_char *row;
int scanline;
/*
* Each scanline is assumed to start off as all
* white (we assume a PhotometricInterpretation
* of ``min-is-black'').
*/
for (op = buf, cc = occ; cc-- > 0;)
*op++ = 0xff;
bp = (u_char *)tif->tif_rawcp;
cc = tif->tif_rawcc;
scanline = tif->tif_scanlinesize;
for (row = buf; (long)occ > 0; occ -= scanline, row += scanline) {
n = *bp++, cc--;
switch (n) {
case LITERALROW:
/*
* The entire scanline is given as literal values.
*/
if (cc < scanline)
goto bad;
memcpy(row, bp, scanline);
bp += scanline;
cc -= scanline;
break;
case LITERALSPAN: {
int off;
/*
* The scanline has a literal span
* that begins at some offset.
*/
off = (bp[0] * 256) + bp[1];
n = (bp[2] * 256) + bp[3];
if (cc < 4+n)
goto bad;
memcpy(row+off, bp+4, n);
bp += 4+n;
cc -= 4+n;
break;
}
default: {
register int npixels = 0, grey;
int imagewidth = tif->tif_dir.td_imagewidth;
/*
* The scanline is composed of a sequence
* of constant color ``runs''. We shift
* into ``run mode'' and interpret bytes
* as codes of the form <color><npixels>
* until we've filled the scanline.
*/
op = row;
for (;;) {
grey = (n>>6) & 0x3;
n &= 0x3f;
while (n-- > 0)
SETPIXEL(op, grey);
if (npixels >= imagewidth)
break;
if (cc == 0)
goto bad;
n = *bp++, cc--;
}
break;
}
}
}
tif->tif_rawcp = (char *)bp;
tif->tif_rawcc = cc;
return (1);
bad:
TIFFError(tif->tif_name, "NeXTDecode: Not enough data for scanline %d",
tif->tif_row);
return (0);
}
int
DECLARE1(TIFFInitNeXT, TIFF*, tif)
{
tif->tif_decoderow = NeXTDecode;
tif->tif_decodestrip = NeXTDecode;
tif->tif_decodetile = NeXTDecode;
return (1);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.