371ad2658c
... and add per-strile offset/bytecount loading capabilities. Part of this commit makes the behaviour that was previously met when libtiff was compiled with -DDEFER_STRILE_LOAD available for default builds when specifying the new 'D' (Deferred) TIFFOpen() flag. In that mode, the [Tile/Strip][ByteCounts/Offsets] arrays are only loaded when first accessed. This can speed-up the opening of files stored on the network when just metadata retrieval is needed. This mode has been used for years by the GDAL library when compiled with its embeded libtiff copy. To avoid potential out-of-tree code (typically codecs) that would use the td_stripbytecount and td_stripoffset array inconditionnaly assuming they have been loaded, those have been suffixed with _p (for protected). The use of the new functions mentionned below is then recommended. Another addition of this commit is the capability of loading only the values of the offset/bytecount of the strile of interest instead of the whole array. This is enabled with the new 'O' (Ondemand) flag of TIFFOpen() (which implies 'D'). That behaviour has also been used by GDAL, which hacked into the td_stripoffset/td_stripbytecount arrays directly. The new code added in the _TIFFFetchStrileValue() and _TIFFPartialReadStripArray() internal functions is mostly a port of what was in GDAL GTiff driver previously. Related to that, the public TIFFGetStrileOffset[WithErr]() and TIFFGetStrileByteCount[WithErr]() functions have been added to API. They are of particular interest when using sparse files (with offset == bytecount == 0) and you want to detect if a strile is present or not without decompressing the data, or updating an existing sparse file. They will also be used to enable a future enhancement where client code can entirely skip bytecount loading in some situtations A new test/defer_strile_loading.c test has been added to test the above capabilities. |
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| archive | ||
| build | ||
| contrib | ||
| html | ||
| libtiff | ||
| m4 | ||
| man | ||
| port | ||
| test | ||
| tools | ||
| .appveyor.yml | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| .travis.yml | ||
| autogen.sh | ||
| ChangeLog | ||
| CMakeLists.txt | ||
| COMMITTERS | ||
| configure.ac | ||
| configure.com | ||
| COPYRIGHT | ||
| HOWTO-RELEASE | ||
| HOWTO-SECURITY-RELEASE | ||
| libtiff-4.pc.in | ||
| Makefile.am | ||
| Makefile.vc | ||
| nmake.opt | ||
| README.md | ||
| RELEASE-DATE | ||
| SConstruct | ||
| tiff.spec | ||
| TODO | ||
| VERSION | ||
TIFF Software Distribution
This file is just a placeholder; all the documentation is now in HTML in the html directory. To view the documentation point your favorite WWW viewer at html/index.html;
e.g.
firefox html/index.html
If you don't have an HTML viewer then you can read the HTML source or fetch a PostScript version of this documentation from the directory
http://download.osgeo.org/libtiff/
If you can't hack either of these options then basically what you want to do is:
% ./configure
% make
% su
# make install
More information, email contacts, and mailing list information can be found online at http://www.simplesystems.org/libtiff/
Source code repository
Bug database
Use and Copyright
Silicon Graphics has seen fit to allow us to give this work away. It is free. There is no support or guarantee of any sort as to its operations, correctness, or whatever. If you do anything useful with all or parts of it you need to honor the copyright notices. I would also be interested in knowing about it and, hopefully, be acknowledged.
The legal way of saying that is:
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.