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Old November 28th 07, 10:44 AM posted to rec.photo.digital
Thomas Richter
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Posts: 52
Default NEWS: HD Photo to become JPEG XR

John Navas schrieb:

For first, this news is old news. It dates back to the JPEG meeting in Lausanne this
summer.


Not that it matters, but the latest developments are much more recent
than that -- the article I posted was published early this month.


Believe me, I'm sitting at the source. This goes back to last summer,
really.

The EXIF issues are currently addressed. Actually, the issue can be solved
rather easily as JPEG2000 has more than enough room to include meta-data.


The problem is that there are competing solutions, rather than a single
standard.


Ehem. I am talking about a standardized solution, really. (-:

You are correct when saying that it has complexity issues, though. The
second major error made during its standardization.


I think it was probably a fatal flaw.


Probably, yes.

* Yet another alternative would be Adobe DNG as an alternative to
proprietary camera RAW, but major camera manufacturers seem resultant to
adopt it.

That's not too unlikely to happen with any new format. Actually, Japanese
camera vendors don't seem - in my reception - feel too hot about JPEG-XR
either.


Microsoft and HP have considerable market clout, Adobe has voiced
support, and inclusion in Vista is a big deal. Samsung is a serious up
and comer, and appears to be interested. Likewise Panasonic. Don't
know about Canon, Sony, Nikon, and Olympus.


All I know is the voting of the Japanese, Singapure and Korean
delegation on this...

It's currently undergoing standardization, however, saying that it can compete with
JPEG2000 in terms of compression performance is IMHO highly overstating its powers. In
fact, from the tests performed, I somewhere sort it near or sometimes even below
baseline JPEG, depending on image content. Note that JPEG-XR is not yet final,
so things will hopefully change to the better, and that for proper tests, one
also has to check with HDR images from the market JPEG-XR actually targets at,
so beware - this is just the status quo. On the other hand, being more critical to
MS press releases won't hurt, either. The best you can do is test yourself.


I have, and I've been impressed.


I have, and I've been disappointed - how did you do your comparisons if
I may ask?
Actually, we made objective and subjective tests (i.e. tested with
various mathematical image quality metrics, and also tested with test
observers), and the results were pretty much comparable, and - as I said
- disappointing. It *did* often preform better than JPEG, but that's not
too hard in first place. Comparing with an arithmetic coding enabled
JPEG (which is just another option nobody uses in traditional JPEG)
showed again different results.
The results so far fit to my own visual impression: HDPhoto seems to
introduce both blocking and blurring artefacts I don't want to see. When
making comparisons, you should make sure you really compress to the same
target file size, otherwise you're running into an apples-vs-oranges
problem. The "quality" scale of HDPhoto is different from the JPEG one.
When really placing images compressed with HDPhoto and JPEG side by
side, it really depends on the image content and on personal taste which
one is better, or which one is worse. Things change noticably when
comparing with more advanced codecs.

Anyhow, as I already said earlier, HDPhoto has hopefully enough
potential to improve its performance, and we haven't really measured
anything beyond 8bpp either, so all of that needs to be considered. All
I doing is presenting the current state of affairs, and the state of
affairs is complicated, unfortunately.

So long,
Thomas