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[wxWidgets.git] / src / tiff / tif_compress.c
1 /* $Header$ */
2
3 /*
4 * Copyright (c) 1988-1997 Sam Leffler
5 * Copyright (c) 1991-1997 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 * Compression Scheme Configuration Support.
31 */
32 #include "tiffiop.h"
33
34 static int
35 TIFFNoEncode(TIFF* tif, char* method)
36 {
37 const TIFFCodec* c = TIFFFindCODEC(tif->tif_dir.td_compression);
38
39 if (c)
40 TIFFError(tif->tif_name, "%s %s encoding is not implemented",
41 c->name, method);
42 else
43 TIFFError(tif->tif_name,
44 "Compression scheme %u %s encoding is not implemented",
45 tif->tif_dir.td_compression, method);
46 return (-1);
47 }
48
49 int
50 _TIFFNoRowEncode(TIFF* tif, tidata_t pp, tsize_t cc, tsample_t s)
51 {
52 (void) pp; (void) cc; (void) s;
53 return (TIFFNoEncode(tif, "scanline"));
54 }
55
56 int
57 _TIFFNoStripEncode(TIFF* tif, tidata_t pp, tsize_t cc, tsample_t s)
58 {
59 (void) pp; (void) cc; (void) s;
60 return (TIFFNoEncode(tif, "strip"));
61 }
62
63 int
64 _TIFFNoTileEncode(TIFF* tif, tidata_t pp, tsize_t cc, tsample_t s)
65 {
66 (void) pp; (void) cc; (void) s;
67 return (TIFFNoEncode(tif, "tile"));
68 }
69
70 static int
71 TIFFNoDecode(TIFF* tif, char* method)
72 {
73 const TIFFCodec* c = TIFFFindCODEC(tif->tif_dir.td_compression);
74
75 if (c)
76 TIFFError(tif->tif_name, "%s %s decoding is not implemented",
77 c->name, method);
78 else
79 TIFFError(tif->tif_name,
80 "Compression scheme %u %s decoding is not implemented",
81 tif->tif_dir.td_compression, method);
82 return (-1);
83 }
84
85 int
86 _TIFFNoRowDecode(TIFF* tif, tidata_t pp, tsize_t cc, tsample_t s)
87 {
88 (void) pp; (void) cc; (void) s;
89 return (TIFFNoDecode(tif, "scanline"));
90 }
91
92 int
93 _TIFFNoStripDecode(TIFF* tif, tidata_t pp, tsize_t cc, tsample_t s)
94 {
95 (void) pp; (void) cc; (void) s;
96 return (TIFFNoDecode(tif, "strip"));
97 }
98
99 int
100 _TIFFNoTileDecode(TIFF* tif, tidata_t pp, tsize_t cc, tsample_t s)
101 {
102 (void) pp; (void) cc; (void) s;
103 return (TIFFNoDecode(tif, "tile"));
104 }
105
106 int
107 _TIFFNoSeek(TIFF* tif, uint32 off)
108 {
109 (void) off;
110 TIFFError(tif->tif_name,
111 "Compression algorithm does not support random access");
112 return (0);
113 }
114
115 int
116 _TIFFNoPreCode(TIFF* tif, tsample_t s)
117 {
118 (void) tif; (void) s;
119 return (1);
120 }
121
122 static int _TIFFtrue(TIFF* tif) { (void) tif; return (1); }
123 static void _TIFFvoid(TIFF* tif) { (void) tif; }
124
125 void LINKAGEMODE
126 _TIFFSetDefaultCompressionState(TIFF* tif)
127 {
128 tif->tif_setupdecode = _TIFFtrue;
129 tif->tif_predecode = _TIFFNoPreCode;
130 tif->tif_decoderow = _TIFFNoRowDecode;
131 tif->tif_decodestrip = _TIFFNoStripDecode;
132 tif->tif_decodetile = _TIFFNoTileDecode;
133 tif->tif_setupencode = _TIFFtrue;
134 tif->tif_preencode = _TIFFNoPreCode;
135 tif->tif_postencode = _TIFFtrue;
136 tif->tif_encoderow = _TIFFNoRowEncode;
137 tif->tif_encodestrip = _TIFFNoStripEncode;
138 tif->tif_encodetile = _TIFFNoTileEncode;
139 tif->tif_close = _TIFFvoid;
140 tif->tif_seek = _TIFFNoSeek;
141 tif->tif_cleanup = _TIFFvoid;
142 tif->tif_defstripsize = _TIFFDefaultStripSize;
143 tif->tif_deftilesize = _TIFFDefaultTileSize;
144 tif->tif_flags &= ~TIFF_NOBITREV;
145 }
146
147 int
148 TIFFSetCompressionScheme(TIFF* tif, int scheme)
149 {
150 const TIFFCodec *c = TIFFFindCODEC(scheme);
151
152 _TIFFSetDefaultCompressionState(tif);
153 /*
154 * Don't treat an unknown compression scheme as an error.
155 * This permits applications to open files with data that
156 * the library does not have builtin support for, but which
157 * may still be meaningful.
158 */
159 return (c ? (*c->init)(tif, scheme) : 1);
160 }
161
162 /*
163 * Other compression schemes may be registered. Registered
164 * schemes can also override the builtin versions provided
165 * by this library.
166 */
167 typedef struct _codec {
168 struct _codec* next;
169 TIFFCodec* info;
170 } codec_t;
171 static codec_t* registeredCODECS = NULL;
172
173 const TIFFCodec*
174 TIFFFindCODEC(uint16 scheme)
175 {
176 const TIFFCodec* c;
177 codec_t* cd;
178
179 for (cd = registeredCODECS; cd; cd = cd->next)
180 if (cd->info->scheme == scheme)
181 return ((const TIFFCodec*) cd->info);
182 for (c = _TIFFBuiltinCODECS; c->name; c++)
183 if (c->scheme == scheme)
184 return (c);
185 return ((const TIFFCodec*) 0);
186 }
187
188 TIFFCodec*
189 TIFFRegisterCODEC(uint16 scheme, const char* name, TIFFInitMethod init)
190 {
191 codec_t* cd = (codec_t*)
192 _TIFFmalloc(sizeof (codec_t) + sizeof (TIFFCodec) + strlen(name)+1);
193
194 if (cd != NULL) {
195 cd->info = (TIFFCodec*) ((tidata_t) cd + sizeof (codec_t));
196 cd->info->name = (char*)
197 ((tidata_t) cd->info + sizeof (TIFFCodec));
198 strcpy(cd->info->name, name);
199 cd->info->scheme = scheme;
200 cd->info->init = init;
201 cd->next = registeredCODECS;
202 registeredCODECS = cd;
203 } else
204 TIFFError("TIFFRegisterCODEC",
205 "No space to register compression scheme %s", name);
206 return (cd->info);
207 }
208
209 void
210 TIFFUnRegisterCODEC(TIFFCodec* c)
211 {
212 codec_t* cd;
213 codec_t** pcd;
214
215 for (pcd = &registeredCODECS; (cd = *pcd); pcd = &cd->next)
216 if (cd->info == c) {
217 *pcd = cd->next;
218 _TIFFfree(cd);
219 return;
220 }
221 TIFFError("TIFFUnRegisterCODEC",
222 "Cannot remove compression scheme %s; not registered", c->name);
223 }