Changes in TIFF v3.9.0beta
==========================

.. table:: References
  :widths: auto

  ======================  ==========================================
  Current Version         v3.9.0beta (:tag:`Release-v3-9-0beta`)
  Previous Version        :doc:`v3.8.2 <v3.8.2>`
  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
-------------

* New :program:`tiffcrop` utility contributed by Richard Nolde.
  :program:`tiffcrop` does the same as :program:`tiffcp`, but also can crop,
  extract, rotate and mirror images.

* :file:`tif_jbig.c`:  Added  support for JBIG compression scheme
  (34661 code), contributed by Lee Howard.

* Totally new implementation of OJPEG module from
  Joris Van Damme. No need to patch libjpeg anymore. Many OJPEG files
  should be supported now that was not supported previously.

Software configuration changes
------------------------------

* :file:`tif_config.wince.h`, :file:`tiffconf.wince.h`, :file:`tif_wince.c`: WinCE-specific
  compatibility stuff from Mateusz Loskot.

* Rename :file:`config.h.vc` and :file:`tif_config.h.vc` to :file:`config.vc.h` and
  :file:`tif_config.vc.h` for easier identification by folks using an IDE.

* :file:`configure`, :file:`configure.ac`: OJPEG support enabled by default (i.e.,
  when conformant JPEG support is enabled).

* :file:`README.vms`, :file:`Makefile.am`, :file:`configure.com`, :file:`libtiff/Makefile.am`,
  :file:`libtiff/tif_config.h-vms`, :file:`libtiff/tif_stream.cxx`,
  :file:`libtiff/tif_vms.c`, :file:`libtiff/tiffconf.h-vms`:
  Added support for OpenVMS by Alexey Chupahin.

* :file:`nmake.opt`: use ``/EHsc`` for VS2005 compatibility.  Also define
  :c:macro:`_CRT_SECURE_NO_DEPRECATE` to avoid noise on VS2005.


Library changes
---------------

* :file:`tif_dirinfo.c` (:c:func:`_TIFFFindFieldInfo`): Don't attempt to
  :c:func:`bsearch` on a :c:macro:`NULL` fieldinfo list.
  (:c:func:`_TIFFFindFieldInfoByName`): Don't attempt to :c:func:`lfind` on a :c:macro:`NULL`
  fieldinfo list.

* :file:`tif_jpeg.c`: Changed :c:func:`JPEGInitializeLibJPEG` so that it
  will convert from decompressor to compressor or compress to decompress
  if required by the force arguments.  This works around a problem in
  where the :c:func:`JPEGFixupTestSubsampling` may cause a decompressor to
  be setup on a directory when later a compressor is required with the
  force flag set.  Occurs with the :program:`addtiffo` program for instance.

* :file:`tif_dirwrite.c`: Fixed swapping of byte arrays stored
  in-place in tag offsets as per bug
  :bugzilla-rs:`1363`

* :file:`tif_getimage.c`: workaround for "Fractional scanline" error
  reading OJPEG images with rowsperstrip that is not a multiple of
  vertical subsampling factor. This bug is mentioned in
  :bugzilla-rs:`1390` and
  `<http://www.asmail.be/msg0054766825.html>`_

* :file:`tif_dirread.c`: Added special function to handle
  ``SubjectDistance`` EXIF tag as per bug
  :bugzilla-rs:`1362`

* :file:`tif_dirread.c`, :file:`tif_read.c`: Type of the byte counters
  changed from :c:type:`tsize_t` to :c:type:`uint32` to be able to work with data arrays
  larger than 2GB. Fixes bug
  :bugzilla-rs:`890`.
  Idea submitted by Matt Hancher.

* :file:`tif_dir.c`: Workaround for incorrect TIFFs with
  ``ExtraSamples == 999`` produced by Corel Draw. As per bug
  :bugzilla-rs:`1490`

* :file:`tif_write.c`: :c:func:`TIFFAppendToStrip` - clear sorted flag if
  we move a strip.
  :bugzilla-rs:`1359`

* :file:`tif_fax3.c`: Save the state of printdir codec dependent method.

* :file:`tif_jpeg.c`: Save the state of printdir codec dependent method
  as per bug
  :bugzilla-rs:`1273`

* :file:`tif_win32.c`: Fixed problem with offset value manipulation
  as per bug
  :bugzilla-rs:`1322`

* :file:`tif_fax3.c`, :file:`tif_next.c`, :file:`tif_pixarlog.c`: Fixed multiple
  vulnerabilities, as per  Gentoo bug ():
  `<http://bugs.gentoo.org/show_bug.cgi?id=142383>`_

* :file:`tif_lzw.c`, :file:`tif_zip.c`: Fixed problems with mixing
  encoding and decoding on the same read-write TIFF handle.  The LZW
  code can now maintain encode and decode state at the same time. The
  ZIP code will switch back and forth as needed.
  :bugzilla-rs:`757`

* :file:`tif_msdos.c`: Avoid handle leak for failed opens.
  c/o Thierry Pierron

* :file:`tif_dirwrite.c`: take care not to flush out buffer of strip/tile
  data in :c:func:`_TIFFWriteDirectory` if :c:macro:`TIFF_BEENWRITING` not set.  Relates
  to bug report by Peng Gao with black strip at bottom of images.

* :file:`tif_dirwrite.c`: make sure to use :c:type:`uint32` for wordcount in
  :c:func:`TIFFWriteNormalTag` if ``writecount`` is :c:macro:`VARIABLE2` for ASCII fields.
  It already seems to have been done for other field types.  Needed
  for :program:`tiffset` on files with geotiff ascii text.

* :file:`tif_dirinfo.c`: Added missed EXIF tag ``ColorSpace`` (40961).

* :file:`tif_dirread.c`: Move IFD fetching code in the separate
  function :c:func:`TIFFFetchDirectory` avoiding code duplication in
  :c:func:`TIFFReadDirectory` and :c:func:`TIFFReadCustomDirectory`.

* :file:`tif_readdir.c`: Added case in :c:func:`EstimateStripByteCounts` for tiled
  files.  Modified :c:func:`TIFFReadDirectory` to not invoke
  :c:func:`EstimateStripByteCounts` for case where entry 0 and 1 are unequal but
  one of them is zero.
  :bugzilla-rs:`1204`

* :file:`tif_open.c`, :file:`tif_dirread.c`, :file:`tiffiop.h`: Move IFD looping
  checking code in the separate function :c:func:`TIFFCheckDirOffset`.

* :file:`tif_aux.c`: Added :c:func:`_TIFFCheckRealloc` function.

* :file:`tif_fax3.c`: Fixed problems in fax decoder as per bug
  :bugzilla-rs:`1194`

* :file:`tif_jbig.c`:  Added  support for JBIG compression scheme
  (34661 code) contributed by Lee Howard. As per bug
  :bugzilla-rs:`896`.

* :file:`tif_getimage.c`: Added support for planarconfig separate
  non-subsampled YCbCr (i.e. separate YCbCr with subsampling ``[1,1]``).

* :file:`tif_getimage.c`: Revision of all RGB(A) put routines:

  * Conversion of unassociated alpha to associated alpha
    now done with more performant LUT, and calculation more
    correct.
  * Conversion of 16bit data to 8bit data now done with
    more performant LUT, and calculation more correct
  * Bugfix of handling of 16bit RGB with unassociated alpha

* :file:`tif_ojpeg.c`: totally new implementation

* :file:`tif_getimage.c`: removed :c:macro:`TIFFTAG_JPEGCOLORMODE` handling
  of OJPEG images in favor of tif_getimage.c native handling of
  YCbCr and desubsampling.

* :file:`tif_jpeg.c`: :c:func:`JPEGVSetField` so that altering the photometric
  interpretation causes the "upsampled" flag to be recomputed.  Fixes
  peculiar bug where photometric flag had to be set before jpegcolormode
  flag.

Tools changes
-------------

* :file:`tiff2ps.c`:  Added support 16-bit images as per bug
  :bugzilla-rs:`1566`.
  Patch from William Bader.

* :file:`tiff2pdf.c`: Fix for :c:macro:`TIFFTAG_JPEGTABLES` tag fetching and
  significant upgrade of the whole utility as per bug
  :bugzilla-rs:`1560`.
  Now we don't need :file:`tiffiop.h` in :program:`tiff2pdf` anymore and will open output
  PDF file using :c:func:`TIFFClientOpen` machinery as it is implemented
  by Leon Bottou.

* :file:`tiffcrop.c`:  New tiffcrop utility contributed
  by Richard Nolde. As per bug
  :bugzilla-rs:`1383`

* :file:`tiff2pdf.c`: Do not assume inches when the resolution units
  do not specified. As per bug
  :bugzilla-rs:`1366`

* :file:`tiffset.c`: Properly handle tags with :c:macro:`TIFF_VARIABLE` writecount.
  As per bug
  :bugzilla-rs:`1350`

* :file:`tif2rgba.c`: This utility does not work properly on big-endian
  architectures. It was fixed including the bug
  :bugzilla-rs:`1149`

* :file:`tiff2pdf.c`: Fix handling of ``-q`` values.
  :bugzilla-rs:`587`

* :file:`tiffcmp.c`: Fixed floating point comparison logic as per bug
  :bugzilla-rs:`1191`

* :file:`tiff2pdf.c`: Fixed buffer overflow condition in
  :c:func:`t2p_write_pdf_string` as per bug
  :bugzilla-rs:`1196`

Contributed software changes
----------------------------

* :file:`contrib/addtiffo/tif_overview.c`: Fix problems with odd sized
  output blocks in :c:func:`TIFF_DownSample_Subsampled`
  (:bugzilla-rs:`1542`).

* :file:`contrib/dbs/xtiff/xtiff.c`: Make xtiff utility compilable.
  Though it is still far from the state of being working and useful.