I want to convert JPG to 256 color IFF. What do I use?

[Karlos]

Assuming you are using OS3.x you should be able to load the jpegs into multiview (provided you have a datatype installed for jpeg files) and then choose "Save As" in the menu to save it as an iff. Mind you, it might save it as IFF24 (not terribly sure about that).

Or you could use one of a multitude of progs including personal paint, photogenics, imagestudio etc (I think the latter is freeware?) to load convert and export as iff 256 colour.

[Karlos]

@CaptainHIT

I'm assuming he wants to convert some images for his workbench? Jpeg loading and colour reduction / dithering to 256-colours is a bit of a pain on 040 - your wallpaper might take a while to render (24/32-bit true colour workbenches are usually much faster since the colour reduction isnt required). IFF on the other hand tends to render very quickly on 8-bit screens.

[Karlos]

Theres a plethora of datatypes for just about every esoteric file format going on aminet under util/dtype :-)

Installation is usually pretty simple - most of them have standard installer scripts you just run and let the installer do it for you. For those that dont, its still usually quite simple:

Typically a datatype has 2 components. A descriptor (used to identify a file format), which goes in Workbench:Devs/Datatypes and the actual datatype itself that goes into Workbench:Classes/Datatypes. The latter file typically has the ".datatype" extension.

Once your datatype is installed, all OS3,x datatype aware applications can load files of that format.

If you just want to view the images on your workbench, once you have the datatype, no conversion is needed. You can use multiview to open the file and all the colour conversion etc. is handled transparently for you. It might take a few seconds to display on an 8-bit screen however. As I say, you can save any image from multiview as iff, but I'm not sure if it is saved as 24-bit format for 24-bit source images (like jpeg).

I'd go with CaptainHit and say that PPaint is a good tool for permanently converting the files to iff 8-bit.