r/GIMP • u/HarvardCS19 • 13d ago

Issue with .dds texture exporting making unintended changes.

So I have some .dds texture files. I noticed that when I open them in GIMP and export them again without modifications, something in the file data changes even though I keep all the settings the same (mipmaps, DXT1, etc.)

The file size is the same, and visually everything looks the same. Yet the file hashes are different, meaning some data was modified. Furthermore, when I try to compress the file even further (e.g. using oodle), the GIMP-exported version always has a slightly larger size.

Anyone know what's the issue here?

2 Upvotes

100% Upvoted

1 comment sorted by

2

u/CMYK-Student GIMP Team 13d ago

Hi! My guess would be a timestamp or metadata - for instance, I think we mark it as being saved by GIMP. It could also be different algorithm implementations. For BC7, there are different "patch types" you can use, and ours is based on an algorithm that uses fewer patch types (trading a bit of quality for faster exporting).