# Changes in TIFF v3.9.0

References
Current Version | v3.9.0 (tag Release-v3-9-0)
Previous Version | v3.9.0beta
Master Download Site | https://download.osgeo.org/libtiff/
Master HTTP Site | http://www.simplesystems.org/libtiff/

This document describes the changes made to the software between the previous and current versions (see above). If you don't find something listed here, then it was not done in this timeframe, or it was not considered important enough to be mentioned. The following information is located here:

## Major changes

- All of the major changes since 3.8.0 were incorporated in the v3.9.0beta release. This is a stable release from a stable maintenance branch which incorporates many bug and security fixes needed by existing users of 3.X.X series libraries. Any future major changes will be in the 4.0.X series of releases.

## Software configuration changes

- Updated autotools: Autoconf 2.64, Automake 1.11, libtool 2.2.6.

- Enabled support for Automake silent build rules (`--enable-silent-rules` or `make V=0`)

- Enabled support for Automake colorized tests.

- Added detection of a 64-bit integer type so that bundled utilities (like tiffcrop) can use it when necessary. Note that this version of libtiff does not require a 64-bit integer type but libtiff 4.0 does.

## Library changes

- `libtiff/Makefile.am`, `libtiff/Makefile.v`: Do not distribute `tiffconf.h`, remove `tif_config.h`/`tiffconf.h` during cleaning. As per bug Remote Sensing bugzilla #1573 [no longer available]

- `tif_dirinfo.c`: `_TIFFMergeFields()` now only merges in field definitions that are missing. Existing definitions are silently ignored. (Remote Sensing bugzilla #1585 [no longer available])

- `tif_write.c`: Rip out the fancy logic in `TIFFAppendToStrip()` for establishing if an existing tile can be rewritten to the same location by comparing the current size to all the other blocks in the same directory. This is dangerous in many situations and can easily corrupt a file. (observed in esoteric GDAL situation that's hard to document). This change involves leaving the stripbytecount[] values unaltered till `TIFFAppendToStrip()`. Now we only write a block back to the same location it used to be at if the new data is the same size or smaller - otherwise we move it to the end of file.

- `tif_dirwrite.c`: Try to avoid writing out a full readbuffer of tile data when writing the directory just because we have `TIFF_BEENWRITING` at some point in the past. This was causing odd junk to be written out in a tile of data when a single tile had an interleaving of reading and writing with reading last. (highlighted by gdal `autotest/gcore/tif_write.py` test 7.)

- `tif_predict.c`: use working buffer in `PredictorEncodeTile()` to avoid modifying callers buffer. GDAL trac #1965

- `tif_predict.c`, `tif_predict.h`, `tif_lzw.c`, `tif_zip.c`: Improvements so that predictor based encoding and decoding works in read-write update mode properly. GDAL trac #1948

- `configure.com`, `libtiff/tif_vms.c`: Better OpenVMS support. Patches from Alexey Chupahin.

- `tif_fax3.c`: fix leak of `FAXCS` state (per bug Remote Sensing bugzilla #1603 [no longer available]).

- `tif_fax3.c`: Make `find0span()` and `find1span()` non-inline to make MSVC 6.0 compiler happy.

- `tif_codec.c`: Avoid `NULL` pointer dereferencing for exotic compression codec codes.

- `tif_dirread.c`: zero `tif->tif_dir` after freeing the directory in `TIFFReadCustomDirectory()`. I don't exactly remember why this was important.

- `tif_dirwrite.c`: Fix potential memory leak writing large double tags.

- `tif_dirread.c`: Fix unchecked `malloc()` result.

- `libtiff/tif_lzw.c`: Properly zero out the codetable. As per bug MapTools bugzilla #1929

- `libtiff/tif_lzw.c`: Properly zero out the string table. Fixes CVE-2008-2327 security issue.

- `libtiff/tif_jbig.c`: Support the JBIG-KIT 2.0 (compatibility with the older versions retained).

- `libtiff/tif_getimage.c`, `tiffio.h`: removed all use of `UaToAa` and `Bitmap16to8` arrays in `TIFFRGBAImage` structure to restore ABI compatibility. These were just an attempt to speed up processing with precalculated tables. MapTools bugzilla #1979

- `libtiff/tif_codec.c`: Avoid printing `c->name` if it does not exist.

- `libtiff/tif_getimage.c`, `tiffio.h`: More ABI corrections. Removed `SubsamplingHor/Ver` from `TIFFRGBAImage` structure. MapTools bugzilla #1980

- `libtiff/tif_jpeg.c`: Avoid errors if the application writes a full strip for the last partial strip in a jpeg compressed file. MapTools bugzilla #1981

- `libtiff/tiffio.h`: GCC will now validate format specifications for `TIFFError()`, `TIFFErrorExt()`, `TIFFWarning()`, and `TIFFWarningExt()` in order to reveal bugs. Cleaned up resulting warnings throughout for 32 bit build only.

- `libtiff/tiffiop.h`: Add private type declarations for `int64`, and `uint64` so that bundled utilities (like tiffcrop) can use it when necessary.

- `libtiff/tif_predict.c`: Add support for 32bit integer horz. predictors. MapTools bugzilla #1911

- `libtiff/tif_luv.c`: Fix handling of tiled logluv images. MapTools bugzilla #2005

- `libtiff/tif_write.c`: do not override the planar configuration to be contig for one sample files if planar configuration is already set. MapTools bugzilla #2057

- `libtiff/tif_lzw.c`: Fix buffer underflow bug. MapTools bugzilla #2065

- `libtiff/tif_luv.c`: correct return codes from `encoderow` to be 1 on success instead of zero. MapTools bugzilla #2069

- `libtiff/tif_print.c` (`TIFFPrintDirectory()`): Applied patch for "tag error may cause segfault in tif_print.c." MapTools bugzilla #1896

## Tools changes

- `tools/tiff2pdf.c`: Fixed setting of alpha value per report on list.

- `tools/tiffsplit.c`: Get rid of unsafe `strcpy()`/`strcat()` calls when doing the filename/path construction.

- `tools/tiff2pdf.c`: More appropriate format string in `t2p_write_pdf_string()`; avoid signed/unsigned mismatch.

- `tools/tiffsplit.c`: Use dynamically allocated array instead of static when constructing output file names.

- `tools/tiffcrop.c`, `man/tiffcrop.1`: Incorporated significant functionality update from Richard Nolde.

- `tools/tiff2ps.c`: Incorporated significant functionality update from Richard Nolde. In particular, support for rotating the image by 90, 180, 270, and 'auto' has been added.

- `tools/tiff2ps.c`: Remove spurious message printed to `stderr`.

- `tools/tiffsplit.c`: fix `sampleformat` to be `shortv` instead of `longv`.

- `tools/rgb2ycbcr.c`, `tools/tiff2rgba.c`: Applied patch for CVE-2009-2347 libtiff: integer overflows in various inter-color space conversion tools. MapTools bugzilla #2079

## Contributed software changes

- None