Mini Shell

Features that may appear in some future release regarding jbig.c:

  - function to prepare incompletely decoded images for display by Xlib

  - use a more efficient resolution-reduction method suggested by
    Dr. Klaus Bartz <bartzkau@kou3.ina.de>

  - investigate whether there is a standard way of embedding JBIG
    into TIFF and implement it (see also RFC 2301)

  - test for and eliminate warning messages from compilers
    other than GCC

  - multichannel (e.g., RGB) support, PPM support

  - add dynamic library target to Makefile (patch by David Woodhouse),
    for the benefit of Linux packagers

The NEWLEN handling in jbig.c remains less than ideal. There is no
easy fix as NEWLEN is inherently incompatible with many of the other
options that jbig.c supports. The whole point of the VLENGTH bit may
have been to allow recipients to choose between a jbig.c (VLENGTH=0)
and jbig85.c (VLENGTH=1) style of decoder implementation. The cleanest
option would really be to remove NEWLEN support entirely from jbig.c
and to urge users who need it to use jbig85.c instead. Short of that,
the new NEWLEN look-ahead architecture from jbig85.c could be
backported to jbig.c, but this would only only slightly increase the
number of cases where the jbig.c decoder could deal with a NEWLEN
marker without a prior invocation of the jbg_newlen() pre-processing
pass.

The following past feature requests for jbig.c probably have become
less important since the release of jbig85.c:

  - compile-time option to remove progressive encoding and
    resolution-reduction support (in the interest of reducing code size)

  - investigate how to best deal with broken BIEs that contain
    multiple NEWLEN marker segments, which are not permitted by ITU-T
    T.85, but which have been observed coming from some fax machines;
    possible options for jbg_newlen(): use first, last, or minimum
    value

  - version of jbg_newlen() for dealing with BIEs that are split
    into several blocks

  - call-back function for progress meter

Features that may appear in some future release regarding jbig85.c:

  - man pages for pbmtojbg85 and jbgtopbm85