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JBIG-KIT revision history
-------------------------

Changes in version 1.6 (2004-06-11)

  - various small changes to reduce the risk of 32-bit unsigned
    integer overflows when dealing with extremely large images

  - robuster treatment of L0 = 0xffffffff

  - minor API modification in jbg_enc_options(): parameter l0 changed
    from type long to unsigned long; previous value now remains
    unchanged when l0 == 0 (was: l0 < 0)

  - lots of type casts added such that the C source code is now
    also compilable as C++

Changes in version 1.5 (2003-06-11)

  - fixed two minor memory leaks (special thanks to Davide Pizzolato
    <ing.davide.pizzolato@libero.it> for locating one of these)

  - jbgtopbm does not attempt any more to parse multiple concatenated
    BIEs (options -m must be used now to enable this feature explicitly),
    in order to handle BIEs with data after the last expected SDE gracefully

  - various extensions to improve support of JBIG fax applications
    (ITU-T T.85 profile):

      o support for maximum adaptive template pixel offset increased
        to MX=127 in both encoder and decoder

      o encoder now has a hook for producing BIEs with a NEWLEN marker
        segment and VLENGTH=1, in order to assist in testing decoders
        for T.85 conformance (see also new pbmtojbg option -Y)

      o a new function jbg_newlen() can be used to scan an
        entire in-memory BIE for NEWLEN marker segments and update the
        YD value in the BIE header, which can be applied to BIE data
        before passing it to the decoder for T.85 compliance
        (Background: the incremental design of the JBIG-KIT decoder
        makes it infeasible to look ahead for NEWLEN marker segments
        that occur after the SDE with the last image line, therefore
        this second pass is necessary to handle the old-style fax
        applications permitted by T.85 in which the low-RAM encoder
        doesn't know the height of the image at the start of
        transmission)

Changes in version 1.4 (2002-04-09)

  - typo fixed in stripe number calculation, which caused encoder and
    decoder to fail on certain image sizes (special thanks to Koen Denecker
    <denecker@elis.rug.ac.be> for locating this one)

Changes in version 1.3 (2002-03-23):

  - bugs fixed in jbg_split_planes(), jbg_dec_merge_planes() that
    caused a failure for more than eight planes per pixel

  - example converters now can handle PGM files with up to 32 bits
    per pixel

Changes in version 1.2 (2000-04-08):

  - bug in the decoder fixed, which caused the rest of the input file
    to be skipped whenever a comment marker was encountered (special
    thanks to Ben Rudiak-Gould <benrg@math.berkeley.edu> for
    reporting this one)

Changes in version 1.1 (1999-11-16):

  - serious bug in the encoder fixed, which for a very small
    percentage of images has caused an unterminated linked list to be
    created internally that could have been responsible for
    segmentation violations or non-terminating encoders
    (special thanks to Hisashi Saiga <saiga@itl.tnr.sharp.co.jp> for
    tracking that one down)

  - minor bug in the "jbgtopbm -d" diagnostic output fixed

Changes in version 1.0 (1998-04-11):

  - two bugs fixed that caused the encoder and decoder to fail
    under certain modes of operation with several bit planes

  - added new functions jbg_split_planes(), jbg_dec_merge_planes(),
    and jbg_dec_getsize_merged() for easy handling of grayscale
    images

  - added support for compressing grayscale PGM files to pbmtojbg
    and jbgtopbm

  - more changes to avoid paranoid compiler warnings

Changes in version 0.9 (1996-01-09):

  - encoder won't break any more on input bitmap data with incorrect
    zero padding

  - pbmtojbg displays a warning if input file has incorrect zero
    padding

  - various minor improvements suggested by Stefan Willer
    <Stefan.Willer@unnet.wupper.DE>

  - many minor changes in order to avoid warnings from paranoid
    compilers

Changes in version 0.8 (1995-09-20):

  - namespace cleared up, all names externally visible from the library
    start now with jbg_ or JBG_

  - minor non-critical bug fixed which caused library to fail compatibility
    test and showed up especially on DEC Alpha systems

  - jbg_dec_gethight() is now called jbg_dec_getheight()

  - filenames conform now to MS-DOS limits

  - Bug in pbmtojbg fixed (handling of ASCII PBM files)

Changes in version 0.7 (1995-06-10):

  - more problems on 16-bit int systems and on Macintosh systems fixed
    (special thanks to Jean-Pierre Gachen <jpg11@calvanet.calvacom.fr>)

  - global Makefile

Changes in version 0.6 (1995-06-08):

  - memory leak fixed

  - should now also work on systems where int is only 16-bit large

  - changes of the JBIG "Technical Corrigendum 1" included (special
    thanks to Dr. Sebestyen from Siemens AG for sending me a copy
    of the draft)

First release: version 0.5 (1995-05-28)


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