Image file formats

[mattclary]

OK, here's a loaded question: What is the "best" file format for still images? TIF, BMP, TGA...? If anyone cares to go into advantages and disadvantages, that would be cool.

[Hiraghm]

Well, I like using TGA with LW because of its built-in alpha channel, but they're big. Jpgs compress well for final output. Bmp is in widespread use, but its files are fat. I'm starting to come around to png as a standard, however.

[Ben_Chapé]

Depends of your needs & what you wanna do with your frames in fact.

* Images for rendering output

i'm quite always using a loseless quality format for output frames :
like a tga32 or a pict32 , this way i always got 24bits(datas)+8bits(of alpha channel) which can help me in compositing/editing.
Datas ammount can be huge but nothing is free in this world :p .
having extra infos is always good too.

I also Output some .rla if i need extra datas (like masks, zbuffers...) for tricky compositing shots.
Sometimes exporting a psd (image filter) is good too to have all extra infos you need (all channels,zbuffer, bonus...)


* Images for Texturing :

i generally use a 100% quality jpeg for textures
(i always use 8bits grayscales ones too for other maps than colormap, this let u optimise memory a bit.others are generally 24bits). But most of my maps are saved in .psd layers too to avoid some suprises.(when you want non-flat datas)

I sometimes use tga32 (to avoid importing another pic for alpha/transparency), or even some compressed bmps.

for 256 colors/8bits i mostly use gif or png.(its quite rare in fact)
and radiance hdri for all light domes or some reflection spheres (sgi format is now becoming a standard too).


In general , i'd say take care of destructives formats like jpeg , specially on surfacing & output , it can creates some serious artefacts.

There's no miracle image formats, only somes adapted or not to your needs.

[mattclary]

Thanks guys!