diff options
Diffstat (limited to 'src/libtiff/tif_next.c')
| -rw-r--r-- | src/libtiff/tif_next.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/src/libtiff/tif_next.c b/src/libtiff/tif_next.c new file mode 100644 index 0000000..7223f7b --- /dev/null +++ b/src/libtiff/tif_next.c @@ -0,0 +1,144 @@ +/* $Id: tif_next.c,v 1.1 2008/10/17 06:16:07 scuri Exp $ */ + +/* + * Copyright (c) 1988-1997 Sam Leffler + * Copyright (c) 1991-1997 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. + */ + +#include "tiffiop.h" +#ifdef NEXT_SUPPORT +/* + * TIFF Library. + * + * NeXT 2-bit Grey Scale Compression Algorithm Support + */ + +#define SETPIXEL(op, v) { \ + switch (npixels++ & 3) { \ + case 0: op[0] = (unsigned char) ((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 +NeXTDecode(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s) +{ + register unsigned char *bp, *op; + register tsize_t cc; + register int n; + tidata_t row; + tsize_t scanline; + + (void) s; + /* + * 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 = (unsigned 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; + _TIFFmemcpy(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 || off+n > scanline) + goto bad; + _TIFFmemcpy(row+off, bp+4, n); + bp += 4+n; + cc -= 4+n; + break; + } + default: { + register int npixels = 0, grey; + unsigned long 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 >= (int) imagewidth) + break; + if (cc == 0) + goto bad; + n = *bp++, cc--; + } + break; + } + } + } + tif->tif_rawcp = (tidata_t) bp; + tif->tif_rawcc = cc; + return (1); +bad: + TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "NeXTDecode: Not enough data for scanline %ld", + (long) tif->tif_row); + return (0); +} + +int +TIFFInitNeXT(TIFF* tif, int scheme) +{ + (void) scheme; + tif->tif_decoderow = NeXTDecode; + tif->tif_decodestrip = NeXTDecode; + tif->tif_decodetile = NeXTDecode; + return (1); +} +#endif /* NEXT_SUPPORT */ + +/* vim: set ts=8 sts=8 sw=8 noet: */ |