Filepack support request

[astrofra]

Hello,

I'm currently doing a series of benchmark and testing several file compression tools.
While testing Filepack with some of my files, I stumbled on a strange case where Filepack seemingly fails when packing a file, reporting the following error :

Code: Select all

toolchain\osdk>filepack -p0 my_file.data my_file.pack
Unable to pack file'my_file.data'

The faulty file is attached (compressed using 7zip, you will have to unzip it first)
Did anyone had a similar experience ?

Thanks for your advice

[Chema]

Never seen it, but looking at the sources, it seems that the file could not be compressed to a size less than the original.

The compression algorithm is quite simple, so this might occur.

[astrofra]

Oh, indeed!
It makes sense!
Thanks for your help

[Dbug]

I guess I could add a better diagnostic message, but yes, basically if the end result does not compress, there's no point in packing it.
Generally this happens when trying to compress already compressed files, FilePack is not designed in being the best packer, it's made to allow almost real time depacking, so it's really targeted at depacking performance as well as being able to unpack a file over itself with as few lost bytes as possible.