Tool for creating JNG files?

[RobertW]

Hi,

Does anyone know of a free Windows tool which can create JNG files? In particular I'd like to convert PNG files to JNG. A small command-line tool would be nice, but a larger interactive tool if necessary.

Thanks,
Rob.

[Sysiphus]

check the free Irfanview.

besides is such a great tool/viewer , last version I saw the other day it supports now saving as JNG, if I did read well. It could open already from quite time, if I remember well.

Be very sure to install both the software and the full installer of the plugins pack. As I guess JNG support is in the plugins pack. Is straight forward as it could be: setup irfanview first, then the installer of the plugins, it takes care of all.

Oh! beware don't go too clicky clicky, there's an screen where google toolbar appears marked. Just unmark it if you don't want google toolbar.

Go and check here:

www.irfanview.com

Since always, to me is the best viewer converter, and outstandingly fast.

Oh, has command line, and quite advanced. has batch processing, surely can be applied also from command line.

[RobertW]

check the free Irfanview.

It can only read JNG files, not write them, according to this page:
http://www.irfanview.com/main_formats.htm

It's also only free for non-commercial use.

Seems weird that JNG is this free open format, yet even the people who created it don't seem to provide tools for creating such files.

Thanks,
Rob.

[Nikster]

I'm curious why you'd want to use JNG, is it for the lossless alpha channel, but you're wanting to compress the main image as jpeg ?

[RobertW]

I'm curious why you'd want to use JNG, is it for the lossless alpha channel, but you're wanting to compress the main image as jpeg ?

More or less. I'd just use JPeg if it supported an alpha channel. Other alternative is to use a JPeg plus a separate 8-bit PNG file for the alpha channel, but it would be nicer to use a single file.

Rob.

[Nikster]

you could use j2k, that has an option to store alpha as lossy/lossless, but I guess it depends on how small your images can get, might not be worth using anything other than PNG for small images.

[Sysiphus]

I'd go for PNG with highest lossless compression, but I guess you had thought of that already.


btw, that kind of formats list can often be out of date.

I mentioned as I magically remembered as the otehr day was reading all 4.10 features list.

go to http://www.irfanview.com/ , click on history of changes, left menu at the site.
"Save support for JNG format (Thanks to Pavel Demchuk)"

(again, you'll need to download and install the plugin pack setup, surely)

About the comercial thing, yup.

[oNyx]

>Other alternative is to use a JPeg plus a separate 8-bit PNG file for the alpha
>channel, but it would be nicer to use a single file.

Having to keep two files in sync is of course pretty annoying. However, you can of course use a single source file (eg png or tga) and automatically generate other flavors by your build process. (If you want to chose on a file by file basis, you'll also may need to generate a file for the mapping.)

I also suggest that you take a look at DXTn, because it loads faster than anything else and it even saves lots of VRAM.

[Sol_HSA]

I also suggest that you take a look at DXTn, because it loads faster than anything else and it even saves lots of VRAM.
..which, on the OpenGL side, is called s3tc, just to confuse things.

[Nikster]

Which is the correct term, I guess microsoft want ppl to believe it's a directx technology ;)