PS1/2 Trying to replace movie files in PS2 iso

[Siesna]

I'm got an interesting idea for a birthday present for a friend. I'd like to replace the cgi movie scenes in her favorite PS2 game with different movie sequences. I know there are ways to rip movies from iso's, but I've not found anywhere offering any information on inserting new movies into an iso. I've worked on similar projects on the psp using umdgen, but it seems the PS2 is veerrryy different. I've tried various iso editing programs like IsoBuster, MagicIso, and CD/DVD Gen, but none of them seem to allow me to directly access the movie files. I was wondering if anyone has any information that could help me?

 

[FAST6191]

A bit old but it works well enough:
http://pagesperso-orange.fr/nomod/

The iml format is what you are after, various apps like UltraISO support it too.