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rick_reno
25th of March 2012 (Sun), 13:59
http://reviews.cnet.com/8301-13970_7-57388241-78/dolby-aims-for-richer-images-with-jpeg-hdr/?tag=nl.e725

photos are at the URL above...

BARCELONA, Spain--High dynamic range (HDR) photography has largely been the province of photo enthusiasts willing to put up with its hassles, but Dolby Laboratories hopes to bring it to the masses with a semi-proprietary technology called JPEG-HDR.
HDR photography began as a way to compensate for cameras' shortcomings compared to the human eye. The biological image sensor can capture a much greater range of dark and bright tones, whereas cameras typically can capture only one, the other, or something in the middle.
That means problems with photos in areas with a wide range of lighting- a scene where someone is standing in a shady foreground when there's a sunlit background, for example. Or the one that constantly frustrates me, stained-glass windows in cathedrals.
With HDR, a camera takes a series of shots at different exposure levels, and a computer combines them. It's getting easier as software automates the process, and it's even a built-in feature with the iPhone 4 and upcoming HTC One X.
But there's still plenty of room for improvement, and Dolby hopes it'll bring some to market with JPEG-HDR, which the company debuted at the Mobile World Congress show here in Barcelona.
JPEG-HDR uses a proprietary processing algorithm to combines multiple exposures. That, in and of itself, isn't particularly new, but what is comes next: Dolby creates from this an HDR image that's backward compatible with ordinary JPEG.

Dolby, Qualcomm shed light on HDR tech (photos) **see URL for photos***


You need special software to explore the full details of the HDR image. But without it, you can see the "tone-mapped" JPEG constructed from the HDR data, said Jean-Marc Matteini, senior director of marketing for imaging at Dolby.
Qualcomm showed off JPEG-HDR on an Android tablet prototype at the show. Its demo showed my bugaboo, the cathedral photo. Tapping on the stained-glass windows exposed them properly while everythinge else went nearly black, and tapping on a dim part of the interior showed it off while the windows washed out to complete whiteness.
Part of the challenge in taking an HDR photograph is capturing images in rapid sequence to minimize problems of subjects such as people or leaves moving from one frame to the next. "We have a great framework for image capture which enables that sort of capture," said Phillippe Decotigne, a Qualcomm product manager. Qualcomm's processors can handle 13 images per second.
Dolby isn't the first to tackle HDR imaging challenges. Perhaps the most prominent alternative is JPEG XR, an "extended range" file format originally developed by Microsoft but now an industry standard. It can accommodate much a broader dynamic range than JPEG.
But JPEG XR uses a different compression algorithm altogether (one that's better, Microsoft argues), which means you can't simply see a JPEG XR file unless you have software that knows how to decode it.
Dolby licenses it technology to others, and JPEG-HDR is another example of that business in action. However, the terms aren't set yet, Matteini said.
"Maybe the decoder is free," so that it's easy for others to view the files, but Dolby would license the encoding technology so that makers of cameras or image-editing software would have to pay.

woos
25th of March 2012 (Sun), 22:25
Sounded encouraging at first, we need a jpeg (or similar) format that is widely supported and supports 16-bit images for web viewing...However, it looks like this isn't it. It's just a hack on top of the regular jpeg format and is proprietary and will require licensing from Dolby. The backwards compatibility is nice, but it looks like it'll be dead on arrival. The article hints that software manufacturers who let you save in the format will need a pay license. This right here will ensure that this format will go absolutely nowhere. It's DOA unless it's freely available. (Might be viewed as unfortunate by those who developed the cool IP, but it's the reality at this point).

What's annoying is that like this article says, Jpeg XR, developed by Microsoft , already solves this problem perfectly. Not only that, but you can take the spec and put it into open source software for free, even GPL'd software (you just can't lift the code from Microsoft's Jpeg XR toolkit, you must write it yourself, no biggie). On top of that you get protection from patent trolls and crap, too, so no lawsuit risk. (Odd for being from MS, then again, MS isn't the same as it was in the 90's...this is the same MS that supported and helped port Silverlight to linux, leading to the hilarity of Silverlight working better than flash in Linux). And software manufacturers like Adobe don't need to pay anything to include support, and if its closed source and such the vendor can just use MS's code, making the barrier to support basically nothing...


This was tried a long time ago, as well, with JPEG 2000. The patents are owned by different companies and such but is available royalty free. However, they couldn't promise that there wasn't some patent somewhere that wasn't owned by one of the membership companies, and that you wouldn't get sued (MS's JPEG XR is solid in that respect). Still, it offered advantages, many software packages now support it, etc. But it never took off at all.

Despite all the advantages, even formats that are basically perfect for everyone like JPEG XR, nothing has managed to take off. The problem is that regular jpeg is good enough for 99.9% of things so it's extremely hard to get everyone to switch.

This Dolby format solves a couple problems and solves backwards compatibility, but if Firefox, Chrome, and IE don't support it and free raw converters and software like Picasa can't support writing to it, why would anyone use it? Not to mention if the base isn't there, why would someone like Adobe put support in lightroom or photoshop (lowers their profits if they have to buy a license, for something that might not even be used)...