
Static analysis of an unknown compression format - kalenz
http://blog.lse.epita.fr/articles/8-static-analysis-of-an-unknown-compression-format.html
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maximilianburke
That's a fairly common compression technique on PS3 titles. Breaking the file
into regularly sized chunks about 64kb (for lzma) permits decompression of the
file in parallel on the SPUs as the dictionary and decompressed data can fit
entirely in local store.

Since optical drives have terrible seek times and low bandwidth most assets
are stored compressed on disc.

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aw3c2
Is there any tool to generate bitmaps from binary files? For example using
each byte as grey value and letting the user specify the column width. Or with
more than one byte and then using color.

Wouldn't this be a trivial and somewhat useful thing to see structure in
binary files?

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frou_dh
When doing simple graphics work at university, I would name files that
contained nothing but pixel data foo.raw and IIRC some image editors would
offer the options you mention when opening the files, then display them fine.
Maybe that was before .raw got associated with cameras (and presumably more
complex).

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throwaway64
raw (can be) interpreted from any stream of binary data, you can open EXEs in
photoshop as RAW, save it as a PNG, transfer it, then resave it as a raw and
it will run.

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fleitz
Reminds me of reverse engineering an email archiving format used by EMC IIRC.
It used an ancient PKZIP compression algorithm to compress COM IStream data
and then wrapped the compressed data in what was essentially a proprietary
linked list.

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ZephyrP
I think this overlooks the classic technique of reverse engineers all over,
IDA Pro!

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PaulHoule
Funny, I was just about to start playing "Tales of Symphonia" when I read
this...

