Hello everyone,
I'm increasingly using high dynamic range images which can eat up serious amounts of filesize.
Jpeg2000 (eg. implemented with jasper (http://www.ece.uvic.ca/~mdadams/jasper/)) can store those quite well (at 16bit per channel which is usually enough for me), but it can be tricky to figure out a reasonable compression-level; certain artefacts are noticable at different exposure-levels and it becomes a stupid process of try&error&tryagain.
So what I'm looking for is some tool that can save jpeg2000, show a preview of the compressed image and lets me change the exposure of the preview.
Unfortunately I haven't found anything usable yet, although that should be a common requirement nowadays.
There are some commercial plugins for photoshop (from luratech and leadtek), but I wasn't really planing to pay for such a simple tool.
Any tip is welcome.
Irfanview will do it I think, you'll need the jpeg2000 dll though.
http://www.irfanview.com/
Problem being that while it lets you set the quality, there is no preview.
Thank you Shockwave, but IrfanView uses a trial-version of LuraTech's encoder - it doesn't save images bigger than 640x480 (atleast not for free) and can't handle hdr (I'm not sure if that's a limitation of LuraWave or IrfanView).
What I'm especially looking for is a preview-function with exposure control, though.
If everything fails I can code a tool myself, I just can't believe such a thing doesn't exist already...
@hellfire:
just saw your post now... i know this lurawave algo... looks like awesome but you can use JPG (with correct settings) to produce smaller code as JPG2000 and with nearly same / sometimes better quality and no extra decoder needed ^^ Just take a look to XNView (freeware n great tool)
Thanks for your hint, Vain.
I want to store high-dynamic range, namely 16 bits of precision per colour-channel.
Unluckily XnView doesn't seem to handle that either.
I don't really care about the output-format, I just require a reasonable amount of compression and some control over compression-artefacts - already tried 'standard' jpeg (see here (http://en.wikipedia.org/wiki/JPEG-HDR)), but the results were disappointing (while jpeg2000 works quite well and directly supports arbitrary bit-depths).
Just wanted to save the work of coding my own tool, but it seems like support for hdr isn't quite where I expected it to be...
I put this custom firmware on my Ixus a few months ago http://chdk.wikia.com/wiki/CHDK (http://chdk.wikia.com/wiki/CHDK). It lets you do HDR and a raft of other stuff. Like you, I barely found any software that can deal with HDR let alone RAW image data at 16bpp.