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BPLOptimize by The Electronic Knights

Short:        IFF ILBM bitplane optimizer
Author:       bifat/tek
Uploader:     bifat@neoscientists.org
Type:         gfx/conv
Version:      0.3
Architecture: i686


About BPLOptimize:

BPLOptimize is an IFF ILBM converter that optimizes bitplanes for
better compression with LZ-like compression algorithms.

It rearranges the individual colors and palette entries of an IFF
ILBM picture in a way that the non-interleaved bitplanes then consist
of more equal bytes and sequences, which as a whole can be compressed
more efficiently. This has got little to do with ILBM's run-length
compression, which may improve too, but this is not what this tool
optimizes for.

The filesize of the compressed result (when converted to raw,
non-interleaved bitplanes) can be similar to the same picture saved 
in PNG format. This can be interesting for OCS Amiga game developers
and demo coders. The goal is NOT to produce smaller IFF ILBM files. 

Interlace, hires, HAM6, EHB, and images with PCHG chunks should be
supported.

An Amiga version is not provided, Amigas do not have the required
computational power. For example, optimizing a 320x256 picture with
16 colors can take more than a minute on a 3ghz personal computer.
It would be faster to order a personal computer and get it delivered
to your place than to run the converter on a real Amiga. Therefore
only binaries for i686 32bit Linux and Windows are provided.


Command overview:

$ bploptimize
argument template:
    -f FROM/A     input IFF ILBM file
    -o TO/A       output IFF ILBM file
    -k KEEP/K     colors/ranges to keep: a-b,c,d-e,...
    -i ITER/N/K   number iterations [default 100000]
    -e EXP/N/K    curve exponent [default 1.5]
    -s SEED/N/K   seed value

Use the -k option to specify colors and color ranges that you wish
to remain unaffected by optimization, e.g. -k 0 would preserve the
background color.


Technical details:

While it does take a long time to optimize a picture, this is not a
brute force, but a heuristic algorithm. With brute force, optimizing
a 32 color picture would take much, much longer.