How to convert .png image files to .tig format?

[DSwizzy]

.TIG images are introduced in the PlayStation 3 release for Sangoku Hime: Senkou no Taika Akatsuki no Haryuu

GARBro can read and extract/convert perfectly fine but if i want to repack said .PNG file as to .TIG file . how do i eatly do that? thank you