1 /* $Header: /usr/people/sam/tiff/libtiff/RCS/tif_fax4.c,v 1.25 1994/09/17 23:22:37 sam Exp $ */
2
3 /*
4 * Copyright (c) 1990, 1991, 1992, 1993, 1994 Sam Leffler
5 * Copyright (c) 1991, 1992, 1993, 1994 Silicon Graphics, Inc.
6 *
7 * Permission to use, copy, modify, distribute, and sell this software and
8 * its documentation for any purpose is hereby granted without fee, provided
9 * that (i) the above copyright notices and this permission notice appear in
10 * all copies of the software and related documentation, and (ii) the names of
11 * Sam Leffler and Silicon Graphics may not be used in any advertising or
12 * publicity relating to the software without the specific, prior written
13 * permission of Sam Leffler and Silicon Graphics.
14 *
15 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
17 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
18 *
19 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
20 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
21 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
22 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
23 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
24 * OF THIS SOFTWARE.
25 */
26
27 /*
28 * TIFF Library.
29 *
30 * CCITT Group 4 Facsimile-compatible
31 * Compression Scheme Support.
32 */
33 #include "tiffiop.h"
34 #include "tif_fax3.h"
35 #include "t4.h"
36
37 /*
38 * Decode the requested amount of data.
39 */
40 static int
Fax4Decode(TIFF * tif,tidata_t buf,tsize_t occ,tsample_t s)41 Fax4Decode(TIFF* tif, tidata_t buf, tsize_t occ, tsample_t s)
42 {
43 Fax3BaseState *sp = (Fax3BaseState *)tif->tif_data;
44 int status;
45
46 _TIFFmemset(buf, 0, occ); /* decoding only sets non-zero bits */
47 while ((long)occ > 0) {
48 status = Fax3Decode2DRow(tif, buf, sp->rowpixels);
49 if (status < 0)
50 return (status == G3CODE_EOF);
51 _TIFFmemcpy(sp->refline, buf, sp->rowbytes);
52 buf += sp->rowbytes;
53 occ -= sp->rowbytes;
54 if (occ != 0)
55 tif->tif_row++;
56 }
57 return (1);
58 }
59
60 /*
61 * Encode the requested amount of data.
62 */
63 static int
Fax4Encode(TIFF * tif,tidata_t bp,tsize_t cc,tsample_t s)64 Fax4Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
65 {
66 Fax3BaseState *sp = (Fax3BaseState *)tif->tif_data;
67
68 while ((long)cc > 0) {
69 if (!Fax3Encode2DRow(tif, bp, sp->refline, sp->rowpixels))
70 return (0);
71 _TIFFmemcpy(sp->refline, bp, sp->rowbytes);
72 bp += sp->rowbytes;
73 cc -= sp->rowbytes;
74 if (cc != 0)
75 tif->tif_row++;
76 }
77 return (1);
78 }
79
80 static
Fax4PostEncode(TIFF * tif)81 Fax4PostEncode(TIFF* tif)
82 {
83 Fax3BaseState *sp = (Fax3BaseState *)tif->tif_data;
84
85 /* terminate strip w/ EOFB */
86 Fax3PutBits(tif, EOL, 12);
87 Fax3PutBits(tif, EOL, 12);
88 if (sp->bit != 8)
89 Fax3FlushBits(tif, sp);
90 return (1);
91 }
92
93 int
TIFFInitCCITTFax4(TIFF * tif)94 TIFFInitCCITTFax4(TIFF* tif)
95 {
96 TIFFInitCCITTFax3(tif); /* reuse G3 compression */
97 tif->tif_decoderow = Fax4Decode;
98 tif->tif_decodestrip = Fax4Decode;
99 tif->tif_decodetile = Fax4Decode;
100 tif->tif_encoderow = Fax4Encode;
101 tif->tif_encodestrip = Fax4Encode;
102 tif->tif_encodetile = Fax4Encode;
103 tif->tif_postencode = Fax4PostEncode;
104 /*
105 * FAX3_NOEOL causes the regular G3 decompression
106 * code to not skip to the EOL mark at the end of
107 * a row (during normal decoding). FAX3_CLASSF
108 * suppresses RTC generation at the end of an image.
109 */
110 tif->tif_options = FAX3_NOEOL|FAX3_CLASSF;
111 return (1);
112 }
113