Filepack support request

Questions, bug reports, features requests, ... about the Oric Software Development Kit. Please indicate clearly in the title the related element (OSDK for generic questions, PictConv, FilePack, XA, Euphoric, etc...) to make it easy to locate messages.

Post Reply
User avatar
astrofra
Private
Posts: 6
Joined: Tue Jan 06, 2015 7:56 pm
Location: Orleans | France
Contact:

Filepack support request

Post by astrofra » Thu Nov 08, 2018 10:03 pm

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 :)
Attachments
my_file.7z
(6.74 KiB) Downloaded 8 times

User avatar
Chema
Game master
Posts: 2302
Joined: Tue Jan 17, 2006 10:55 am
Location: Gijón, SPAIN
Contact:

Re: Filepack support request

Post by Chema » Thu Nov 08, 2018 10:11 pm

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.

User avatar
astrofra
Private
Posts: 6
Joined: Tue Jan 06, 2015 7:56 pm
Location: Orleans | France
Contact:

Re: Filepack support request

Post by astrofra » Thu Nov 08, 2018 10:19 pm

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

User avatar
Dbug
Site Admin
Posts: 2738
Joined: Fri Jan 06, 2006 10:00 pm
Location: Oslo, Norway
Contact:

Re: Filepack support request

Post by Dbug » Fri Nov 09, 2018 7:12 pm

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.

Post Reply