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.ab file format

PostPosted: Tue Aug 14, 2007 9:29 am
by number67
I don't run windows, which makes using ArmyBuilder quite hard, so I'm having a go at writing my own army organiser sort of thing.

Obviously, I don't want to have to retype all the useful information that you good people have spent hours transcribing, so I'd quite like to use the .ab files that are currently available on the interweb.

I've had a look at the internal format of the .ab files and they look reasonably sensible, with a directory structure at the end, pointing to various blocks of compressed data, very much like the PKZIP file format.

But I have two problems, one serious one not:

1) Not serious: The checksum used to verify the compressed blocks is not either of the zlib checksums i.e. alder32 or crc32. Does anyone know the polynomial that is used for these checksums?

2) Serious (and a pretty big ask): The compressed data is not in any format I recognise. After a bit of investigation of the binaries (using strings) it appears that they are using a proprietary compressor from Greenleaf software, which may or may not be "PKZIP compatible". Does anyone how to decode this data?

Re: .ab file format

PostPosted: Tue Aug 14, 2007 1:35 pm
by jlong05
number67 wrote:I don't run windows, which makes using ArmyBuilder quite hard, so I'm having a go at writing my own army organiser sort of thing.

Obviously, I don't want to have to retype all the useful information that you good people have spent hours transcribing, so I'd quite like to use the .ab files that are currently available on the interweb.

I've had a look at the internal format of the .ab files and they look reasonably sensible, with a directory structure at the end, pointing to various blocks of compressed data, very much like the PKZIP file format.

But I have two problems, one serious one not:

1) Not serious: The checksum used to verify the compressed blocks is not either of the zlib checksums i.e. alder32 or crc32. Does anyone know the polynomial that is used for these checksums?

2) Serious (and a pretty big ask): The compressed data is not in any format I recognise. After a bit of investigation of the binaries (using strings) it appears that they are using a proprietary compressor from Greenleaf software, which may or may not be "PKZIP compatible". Does anyone how to decode this data?

As we are all just the datafile maintainers for the 40k files I dont think any of us woudl have those answers. Colin and Rob at Lonewolf are pretty cool guys. They may be inetersted in your assistance in creating non-windows based versions of the AB software. You may want to check in with either of them.

PostPosted: Tue Aug 14, 2007 4:40 pm
by harkan
one other thing to be aware of - from the title of the post being ".ab" is it AB v2.x you are looking at as this is now unsupported. It may be easier to rowk with AB3.1 and above as the datafiles are all in xml and the .abz file is created at initial compilation - that may make life a LOT easier for you?

PostPosted: Tue Aug 14, 2007 8:44 pm
by number67
harkan wrote:one other thing to be aware of - from the title of the post being ".ab"


I was working on the files that I've managed to download, like this one modules.php?name=Downloads&d_op=getit&lid=76
which all have the extension .ab

PostPosted: Tue Aug 14, 2007 10:33 pm
by harkan
yeah they are for AB2.2 and are confusing enough even using an editor - if it is not too much work for you I would seriously recomend going over to look at the current release - v1.25a. If you need it unpacking and sending then pm me your email addy and I will do

PostPosted: Wed Aug 15, 2007 11:15 am
by number67
harkan wrote:yeah they are for AB2.2 and are confusing enough even using an editor - if it is not too much work for you I would seriously recomend going over to look at the current release - v1.25a. If you need it unpacking and sending then pm me your email addy and I will do


I'm confused.

Is the v1.25a file that is linked on the download page and that I quoted in the above post version 2 or version 3? It ends .ab and is of the format I have described.

PostPosted: Wed Aug 15, 2007 2:33 pm
by Rayne
Its version 3, and i think its file extension is .abz

PostPosted: Wed Aug 15, 2007 3:29 pm
by harkan
dohhhh, sorry my bad - that is the v3.1 file and it is a .ab file (the compressed version), when uncompressed they come out to .dat, .aug, .ext and .def files which may be better for you to work from??

the .abz file Rayne is referring to is the compilation file that AB creates when it compiles the files (dat etc) on start up