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Tue Aug 25 22:50:44 CEST 2009
If it's so easy to add support for it, we could think about funding
JPEG-LS integration into apps/tools we'd need for this archiving
project. Of course, that's only reasonable with FOSS - and impossible
with proprietary apps (which we try to avoid using at all, since vendor
lock-in seems to be standard in "professional" video handling gear).
Licensing and Implementation of JPEG-LS libs/tools is yet unclear (and
as it seems, also for Debian packagers [4]):
Did the FFmpeg team implement the JPEG-LS codec themselves or use an
existing implementation? I'm asking, because the only available
implementations I've found so far that look a bit reliable (and still
maintained) are Loco-I by HP [1], CharLS [2] and the UBC implementation
(which seems to be no longer accessible [3])
However, I think if I can find a commandline tool for
"JPEG-LS-to-something" conversion, I could pipe that together with any
image processing chain I'd need, so lack of client-side apps would not
really matter. The additional overhead would probably still be less than
handling JP2.
> Also as you mentioned support, how many jpeg2000 implementations support
> retrieving lower resolution content? ive not checked but i would suspect
> that not all support this.
>
It's not mandatory, I'm just used thinking in possible long-term
requirements/optimizations when thinking about archives.
It would be awesome if JPIP (http://en.wikipedia.org/wiki/JPIP) was
already a widespread option, but you're right: Sophisticated JP2
handling is hardly implemented. :(
> ffmpeg supports btw, decoding most DCT based codecs in lower resolution.
>
Sounds useful - Although I'm not sure if I got you 100% right: "lower
resolution" means less pixels or less quality?
Is there any documentation about that you could point me to?
Thanks again for your time,
Peter
== References ==
[1] http://www.hpl.hp.com/loco/
[2] http://charls.codeplex.com/documentation
[3] http://www.stat.columbia.edu/~jakulin/jpeg-ls/
[4] http://www.mail-archive.com/debian-legal@lists.debian.org/msg40029.html
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