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1 | <!-- Creator : groff version 1.18.1 --> |
2 | <!-- CreationDate: Mon Mar 13 18:03:08 2006 --> | |
3 | <html> | |
4 | <head> | |
5 | <meta name="generator" content="groff -Thtml, see www.gnu.org"> | |
6 | <meta name="Content-Style" content="text/css"> | |
7 | <title>TIFFOpen</title> | |
8 | </head> | |
9 | <body> | |
10 | ||
11 | <h1 align=center>TIFFOpen</h1> | |
12 | <a href="#NAME">NAME</a><br> | |
13 | <a href="#SYNOPSIS">SYNOPSIS</a><br> | |
14 | <a href="#DESCRIPTION">DESCRIPTION</a><br> | |
15 | <a href="#OPTIONS">OPTIONS</a><br> | |
16 | <a href="#BYTE ORDER">BYTE ORDER</a><br> | |
17 | <a href="#RETURN VALUES">RETURN VALUES</a><br> | |
18 | <a href="#DIAGNOSTICS">DIAGNOSTICS</a><br> | |
19 | <a href="#SEE ALSO">SEE ALSO</a><br> | |
20 | ||
21 | <hr> | |
22 | <a name="NAME"></a> | |
23 | <h2>NAME</h2> | |
24 | <!-- INDENTATION --> | |
25 | <table width="100%" border=0 rules="none" frame="void" | |
26 | cols="2" cellspacing="0" cellpadding="0"> | |
27 | <tr valign="top" align="left"> | |
28 | <td width="8%"></td> | |
29 | <td width="91%"> | |
30 | <p>TIFFOpen, TIFFFdOpen, TIFFClientOpen − open a | |
31 | <small>TIFF</small> file for reading or writing</p> | |
32 | </td> | |
33 | </table> | |
34 | <a name="SYNOPSIS"></a> | |
35 | <h2>SYNOPSIS</h2> | |
36 | <!-- INDENTATION --> | |
37 | <table width="100%" border=0 rules="none" frame="void" | |
38 | cols="2" cellspacing="0" cellpadding="0"> | |
39 | <tr valign="top" align="left"> | |
40 | <td width="8%"></td> | |
41 | <td width="91%"> | |
42 | <p><b>#include <tiffio.h></b></p> | |
43 | <!-- INDENTATION --> | |
44 | <p><b>TIFF* TIFFOpen(const char *</b><i>filename</i><b>, | |
45 | const char *</b><i>mode</i><b>)<br> | |
46 | TIFF* TIFFFdOpen(const int</b> <i>fd</i><b>, const char | |
47 | *</b><i>filename</i><b>, const char | |
48 | *</b><i>mode</i><b>)</b></p> | |
49 | <!-- INDENTATION --> | |
50 | <p><b>typedef tsize_t (*TIFFReadWriteProc)(thandle_t, | |
51 | tdata_t, tsize_t);<br> | |
52 | typedef toff_t (*TIFFSeekProc)(thandle_t, toff_t, int);<br> | |
53 | typedef int (*TIFFCloseProc)(thandle_t);<br> | |
54 | typedef toff_t (*TIFFSizeProc)(thandle_t);<br> | |
55 | typedef int (*TIFFMapFileProc)(thandle_t, tdata_t*, | |
56 | toff_t*);<br> | |
57 | typedef void (*TIFFUnmapFileProc)(thandle_t, tdata_t, | |
58 | toff_t);</b></p> | |
59 | <!-- INDENTATION --> | |
60 | <p><b>TIFF* TIFFClientOpen(const char | |
61 | *</b><i>filename</i><b>, const char *</b><i>mode</i><b>, | |
62 | thandle_t</b> <i>clientdata</i><b>, TIFFReadWriteProc</b> | |
63 | <i>readproc</i><b>, TIFFReadWriteProc</b> | |
64 | <i>writeproc</i><b>, TIFFSeekProc</b> <i>seekproc</i><b>, | |
65 | TIFFCloseProc</b> <i>closeproc</i><b>, TIFFSizeProc</b> | |
66 | <i>sizeproc</i><b>, TIFFMapFileProc</b> <i>mapproc</i><b>, | |
67 | TIFFUnmapFileProc</b> <i>unmapproc</i><b>)</b></p> | |
68 | </td> | |
69 | </table> | |
70 | <a name="DESCRIPTION"></a> | |
71 | <h2>DESCRIPTION</h2> | |
72 | <!-- INDENTATION --> | |
73 | <table width="100%" border=0 rules="none" frame="void" | |
74 | cols="2" cellspacing="0" cellpadding="0"> | |
75 | <tr valign="top" align="left"> | |
76 | <td width="8%"></td> | |
77 | <td width="91%"> | |
78 | <p><i>TIFFOpen</i> opens a <small>TIFF</small> file whose | |
79 | name is <i>filename</i> and returns a handle to be used in | |
80 | subsequent calls to routines in <i>libtiff</i>. If the open | |
81 | operation fails, then zero is returned. The <i>mode</i> | |
82 | parameter specifies if the file is to be opened for reading | |
83 | (‘‘r’’), writing | |
84 | (‘‘w’’), or appending | |
85 | (‘‘a’’) and, optionally, whether to | |
86 | override certain default aspects of library operation (see | |
87 | below). When a file is opened for appending, existing data | |
88 | will not be touched; instead new data will be written as | |
89 | additional subfiles. If an existing file is opened for | |
90 | writing, all previous data is overwritten.</p> | |
91 | <!-- INDENTATION --> | |
92 | <p>If a file is opened for reading, the first | |
93 | <small>TIFF</small> directory in the file is automatically | |
94 | read (also see <i>TIFFSetDirectory</i>(3TIFF) for reading | |
95 | directories other than the first). If a file is opened for | |
96 | writing or appending, a default directory is automatically | |
97 | created for writing subsequent data. This directory has all | |
98 | the default values specified in <small>TIFF</small> Revision | |
99 | 6.0: <i>BitsPerSample</i>=1, <i>ThreshHolding</i>=bilevel | |
100 | art scan, <i>FillOrder</i>=1 (most significant bit of each | |
101 | data byte is filled first), <i>Orientation</i>=1 (the 0th | |
102 | row represents the visual top of the image, and the 0th | |
103 | column represents the visual left hand side), | |
104 | <i>SamplesPerPixel</i>=1, <i>RowsPerStrip</i>=infinity, | |
105 | <i>ResolutionUnit</i>=2 (inches), and <i>Compression</i>=1 | |
106 | (no compression). To alter these values, or to define values | |
107 | for additional fields, <i>TIFFSetField</i>(3TIFF) must be | |
108 | used.</p> | |
109 | <!-- INDENTATION --> | |
110 | <p><i>TIFFFdOpen</i> is like <i>TIFFOpen</i> except that it | |
111 | opens a <small>TIFF</small> file given an open file | |
112 | descriptor <i>fd</i>. The file’s name and mode must | |
113 | reflect that of the open descriptor. The object associated | |
114 | with the file descriptor <b>must support random | |
115 | access</b>.</p> | |
116 | <!-- INDENTATION --> | |
117 | <p><i>TIFFClientOpen</i> is like <i>TIFFOpen</i> except that | |
118 | the caller supplies a collection of functions that the | |
119 | library will use to do <small>UNIX</small> -like I/O | |
120 | operations. The <i>readproc</i> and <i>writeproc</i> are | |
121 | called to read and write data at the current file position. | |
122 | <i>seekproc</i> is called to change the current file | |
123 | position a la <i>lseek</i>(2). <i>closeproc</i> is invoked | |
124 | to release any resources associated with an open file. | |
125 | <i>sizeproc</i> is invoked to obtain the size in bytes of a | |
126 | file. <i>mapproc</i> and <i>unmapproc</i> are called to map | |
127 | and unmap a file’s contents in memory; c.f. | |
128 | <i>mmap</i>(2) and <i>munmap</i>(2). The <i>clientdata</i> | |
129 | parameter is an opaque ‘‘handle’’ | |
130 | passed to the client-specified routines passed as parameters | |
131 | to <i>TIFFClientOpen</i>.</p> | |
132 | </td> | |
133 | </table> | |
134 | <a name="OPTIONS"></a> | |
135 | <h2>OPTIONS</h2> | |
136 | <!-- INDENTATION --> | |
137 | <table width="100%" border=0 rules="none" frame="void" | |
138 | cols="2" cellspacing="0" cellpadding="0"> | |
139 | <tr valign="top" align="left"> | |
140 | <td width="8%"></td> | |
141 | <td width="91%"> | |
142 | <p>The open mode parameter can include the following flags | |
143 | in addition to the ‘‘r’’, | |
144 | ‘‘w’’, and | |
145 | ‘‘a’’ flags. Note however that | |
146 | option flags must follow the read-write-append | |
147 | specification.</p> | |
148 | </td> | |
149 | </table> | |
150 | <!-- TABS --> | |
151 | <table width="100%" border=0 rules="none" frame="void" | |
152 | cols="5" cellspacing="0" cellpadding="0"> | |
153 | <tr valign="top" align="left"> | |
154 | <td width="10%"></td> | |
155 | <td width="2%"> | |
156 | ||
157 | <p><b>l</b></p> | |
158 | </td> | |
159 | <td width="6%"></td> | |
160 | <td width="80%"> | |
161 | ||
162 | <p>When creating a new file force information be written | |
163 | with Little-Endian byte order (but see below). By default | |
164 | the library will create new files using the native | |
165 | <small>CPU</small> byte order.</p> | |
166 | </td> | |
167 | <td width="0%"> | |
168 | </td> | |
169 | <tr valign="top" align="left"> | |
170 | <td width="10%"></td> | |
171 | <td width="2%"> | |
172 | ||
173 | <p><b>b</b></p> | |
174 | </td> | |
175 | <td width="6%"></td> | |
176 | <td width="80%"> | |
177 | ||
178 | <p>When creating a new file force information be written | |
179 | with Big-Endian byte order (but see below). By default the | |
180 | library will create new files using the native | |
181 | <small>CPU</small> byte order.</p> | |
182 | </td> | |
183 | <td width="0%"> | |
184 | </td> | |
185 | <tr valign="top" align="left"> | |
186 | <td width="10%"></td> | |
187 | <td width="2%"> | |
188 | ||
189 | <p><b>L</b></p> | |
190 | </td> | |
191 | <td width="6%"></td> | |
192 | <td width="80%"> | |
193 | ||
194 | <p>Force image data that is read or written to be treated | |
195 | with bits filled from Least Significant Bit ( | |
196 | <small>LSB</small> ) to Most Significant Bit ( | |
197 | <small>MSB</small> ). Note that this is the opposite to the | |
198 | way the library has worked from its inception.</p> | |
199 | </td> | |
200 | <td width="0%"> | |
201 | </td> | |
202 | <tr valign="top" align="left"> | |
203 | <td width="10%"></td> | |
204 | <td width="2%"> | |
205 | ||
206 | <p><b>B</b></p> | |
207 | </td> | |
208 | <td width="6%"></td> | |
209 | <td width="80%"> | |
210 | ||
211 | <p>Force image data that is read or written to be treated | |
212 | with bits filled from Most Significant Bit ( | |
213 | <small>MSB</small> ) to Least Significant Bit ( | |
214 | <small>LSB</small> ); this is the default.</p> | |
215 | </td> | |
216 | <td width="0%"> | |
217 | </td> | |
218 | <tr valign="top" align="left"> | |
219 | <td width="10%"></td> | |
220 | <td width="2%"> | |
221 | ||
222 | <p><b>H</b></p> | |
223 | </td> | |
224 | <td width="6%"></td> | |
225 | <td width="80%"> | |
226 | ||
227 | <p>Force image data that is read or written to be treated | |
228 | with bits filled in the same order as the native | |
229 | <small>CPU.</small></p> | |
230 | </td> | |
231 | <td width="0%"> | |
232 | </td> | |
233 | <tr valign="top" align="left"> | |
234 | <td width="10%"></td> | |
235 | <td width="2%"> | |
236 | ||
237 | <p><b>M</b></p> | |
238 | </td> | |
239 | <td width="6%"></td> | |
240 | <td width="80%"> | |
241 | ||
242 | <p>Enable the use of memory-mapped files for images opened | |
243 | read-only. If the underlying system does not support | |
244 | memory-mapped files or if the specific image being opened | |
245 | cannot be memory-mapped then the library will fallback to | |
246 | using the normal system interface for reading information. | |
247 | By default the library will attempt to use memory-mapped | |
248 | files.</p> | |
249 | </td> | |
250 | <td width="0%"> | |
251 | </td> | |
252 | <tr valign="top" align="left"> | |
253 | <td width="10%"></td> | |
254 | <td width="2%"> | |
255 | ||
256 | <p><b>m</b></p> | |
257 | </td> | |
258 | <td width="6%"></td> | |
259 | <td width="80%"> | |
260 | ||
261 | <p>Disable the use of memory-mapped files.</p> | |
262 | </td> | |
263 | <td width="0%"> | |
264 | </td> | |
265 | <tr valign="top" align="left"> | |
266 | <td width="10%"></td> | |
267 | <td width="2%"> | |
268 | ||
269 | <p><b>C</b></p> | |
270 | </td> | |
271 | <td width="6%"></td> | |
272 | <td width="80%"> | |
273 | ||
274 | <p>Enable the use of ‘‘strip | |
275 | chopping’’ when reading images that are | |
276 | comprised of a single strip or tile of uncompressed data. | |
277 | Strip chopping is a mechanism by which the library will | |
278 | automatically convert the single-strip image to multiple | |
279 | strips, each of which has about 8 Kilobytes of data. This | |
280 | facility can be useful in reducing the amount of memory used | |
281 | to read an image because the library normally reads each | |
282 | strip in its entirety. Strip chopping does however alter the | |
283 | apparent contents of the image because when an image is | |
284 | divided into multiple strips it looks as though the | |
285 | underlying file contains multiple separate strips. Finally, | |
286 | note that default handling of strip chopping is a | |
287 | compile-time configuration parameter. The default behaviour, | |
288 | for backwards compatibility, is to enable strip | |
289 | chopping.</p> | |
290 | </td> | |
291 | <td width="0%"> | |
292 | </td> | |
293 | <tr valign="top" align="left"> | |
294 | <td width="10%"></td> | |
295 | <td width="2%"> | |
296 | ||
297 | <p><b>c</b></p> | |
298 | </td> | |
299 | <td width="6%"></td> | |
300 | <td width="80%"> | |
301 | ||
302 | <p>Disable the use of strip chopping when reading | |
303 | images.</p> | |
304 | </td> | |
305 | <td width="0%"> | |
306 | </td> | |
307 | <tr valign="top" align="left"> | |
308 | <td width="10%"></td> | |
309 | <td width="2%"> | |
310 | ||
311 | <p><b>h</b></p> | |
312 | </td> | |
313 | <td width="6%"></td> | |
314 | <td width="80%"> | |
315 | ||
316 | <p>Read TIFF header only, do not load the first image | |
317 | directory. That could be useful in case of the broken first | |
318 | directory. We can open the file and proceed to the other | |
319 | directories.</p> | |
320 | </td> | |
321 | <td width="0%"> | |
322 | </td> | |
323 | </table> | |
324 | <a name="BYTE ORDER"></a> | |
325 | <h2>BYTE ORDER</h2> | |
326 | <!-- INDENTATION --> | |
327 | <table width="100%" border=0 rules="none" frame="void" | |
328 | cols="2" cellspacing="0" cellpadding="0"> | |
329 | <tr valign="top" align="left"> | |
330 | <td width="8%"></td> | |
331 | <td width="91%"> | |
332 | <p>The <small>TIFF</small> specification (<b>all | |
333 | versions</b>) states that compliant readers <i>must be | |
334 | capable of reading images written in either byte order</i>. | |
335 | Nonetheless some software that claims to support the reading | |
336 | of <small>TIFF</small> images is incapable of reading images | |
337 | in anything but the native <small>CPU</small> byte order on | |
338 | which the software was written. (Especially notorious are | |
339 | applications written to run on Intel-based machines.) By | |
340 | default the library will create new files with the native | |
341 | byte-order of the <small>CPU</small> on which the | |
342 | application is run. This ensures optimal performance and is | |
343 | portable to any application that conforms to the TIFF | |
344 | specification. To force the library to use a specific | |
345 | byte-order when creating a new file the | |
346 | ‘‘b’’ and | |
347 | ‘‘l’’ option flags may be included | |
348 | in the call to open a file; for example, | |
349 | ‘‘wb’’ or | |
350 | ‘‘wl’’.</p> | |
351 | </td> | |
352 | </table> | |
353 | <a name="RETURN VALUES"></a> | |
354 | <h2>RETURN VALUES</h2> | |
355 | <!-- INDENTATION --> | |
356 | <table width="100%" border=0 rules="none" frame="void" | |
357 | cols="2" cellspacing="0" cellpadding="0"> | |
358 | <tr valign="top" align="left"> | |
359 | <td width="8%"></td> | |
360 | <td width="91%"> | |
361 | <p>Upon successful completion <i>TIFFOpen</i>, | |
362 | <i>TIFFFdOpen</i>, and <i>TIFFClientOpen</i> return a | |
363 | <small>TIFF</small> pointer. Otherwise, NULL is | |
364 | returned.</p> | |
365 | </td> | |
366 | </table> | |
367 | <a name="DIAGNOSTICS"></a> | |
368 | <h2>DIAGNOSTICS</h2> | |
369 | <!-- INDENTATION --> | |
370 | <table width="100%" border=0 rules="none" frame="void" | |
371 | cols="2" cellspacing="0" cellpadding="0"> | |
372 | <tr valign="top" align="left"> | |
373 | <td width="8%"></td> | |
374 | <td width="91%"> | |
375 | <p>All error messages are directed to the | |
376 | <i>TIFFError</i>(3TIFF) routine. Likewise, warning messages | |
377 | are directed to the <i>TIFFWarning</i>(3TIFF) routine.</p> | |
378 | <!-- INDENTATION --> | |
379 | <p><b>"%s": Bad mode</b>. The specified | |
380 | <i>mode</i> parameter was not one of | |
381 | ‘‘r’’ (read), | |
382 | ‘‘w’’ (write), or | |
383 | ‘‘a’’ (append).</p> | |
384 | <!-- INDENTATION --> | |
385 | <p><b>%s: Cannot open</b>. <i>TIFFOpen</i>() was unable to | |
386 | open the specified filename for read/writing.</p> | |
387 | <!-- INDENTATION --> | |
388 | <p><b>Cannot read TIFF header</b>. An error occurred while | |
389 | attempting to read the header information.</p> | |
390 | <!-- INDENTATION --> | |
391 | <p><b>Error writing TIFF header</b>. An error occurred while | |
392 | writing the default header information for a new file.</p> | |
393 | <!-- INDENTATION --> | |
394 | <p><b>Not a TIFF file, bad magic number %d (0x%x)</b>. The | |
395 | magic number in the header was not (hex) 0x4d4d or (hex) | |
396 | 0x4949.</p> | |
397 | <!-- INDENTATION --> | |
398 | <p><b>Not a TIFF file, bad version number %d (0x%x)</b>. The | |
399 | version field in the header was not 42 (decimal).</p> | |
400 | <!-- INDENTATION --> | |
401 | <p><b>Cannot append to file that has opposite byte | |
402 | ordering</b>. A file with a byte ordering opposite to the | |
403 | native byte ordering of the current machine was opened for | |
404 | appending (‘‘a’’). This is a | |
405 | limitation of the library.</p> | |
406 | </td> | |
407 | </table> | |
408 | <a name="SEE ALSO"></a> | |
409 | <h2>SEE ALSO</h2> | |
410 | <!-- INDENTATION --> | |
411 | <table width="100%" border=0 rules="none" frame="void" | |
412 | cols="2" cellspacing="0" cellpadding="0"> | |
413 | <tr valign="top" align="left"> | |
414 | <td width="8%"></td> | |
415 | <td width="91%"> | |
416 | <p><i>libtiff</i>(3TIFF), <i>TIFFClose</i>(3TIFF)</p> | |
417 | </td> | |
418 | </table> | |
419 | <hr> | |
420 | </body> | |
421 | </html> |