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Old 19th January 2017, 18:37   #148  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
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Quote:
Originally Posted by dipje View Post
jpeg-xr is still format for my own photography stuff. lossless, all the image formats I want (16-bit is a bit of a minimum) and it encodes 24+ megapixel images under 4 seconds, and has full exif support with / through exiftool. I happily take a file that is a few MBs more in size compared to other modern lossless image formats.. the convenience just beats it all for me. Nothing of this has anything to do with web-images, end-delivery (like, regular old jpg files) or the video world .

I'm just dreaming of the day when there is a modern ILC camera that has jpeg-xr as a write option. Either write complete done images (like the old jpg files) but in 16 bit so that they're actually still somewhat gradable and editable after the fact... or use jpeg-xr's floating-point / hdr support to write an image that is debayered and pretty much good to go, but still has all the information 'past 1.0' or under '0.0' that the image sensor captured (no need to throw anything away while still including the tone mapping). Seems perfect to me, but it just never took of .
Well, you certainly understand what the goals were for JPEG-XR! Unfortunately Microsoft cut resources for it due to it not being critical to any one business group willing to fund the entire effort - a common problem in the Massive Microsoft Media Meltdown of 2006-2012.

Quote:
What I read from it it isn't even wavelet based, just 'plain old' DCT, just bigger and more of it so to speak. They described it as 'an enhanced DCT for decoders with more memory, and support for 16bit and lossless'. I think the HDR isn't real floating point but just 16-bit integers with a mapping curve or something. Still, it's so fast compared to all the webp / bpg / flif formats.
It actually alternated between a DCT-like and wavelet-like transform for each layer.

Quote:
BPG comes close though now that they're using x265 instead of the reference encoder. Much faster and lossless sizes are good, although 'limited' to 12bit. jpeg-xr is faster, has true 16bit and I don't have to save the metadata in a separate file next to the image. Close, but still a no brainer for me.
There are 16-bit HEVC profiles, particularly Main 4:4:4 16 Still Picture. Which should be great for photography. And certainly HEVC should offer smaller lossless encoding, and much smaller visually lossless encoding, than J2K or JPEG-XR. Intra-frame prediction with lots of block sizes is a good thing!

I don't know how well that profile would encode RAW sensor data, but it certainly would work for anything normalized to gamma, PQ, or similar EOTF.

HEVC v3 includes some color video profiles up to 14-bit (which I don't know that anything supports), but 16-bit remains intra/still encoding only. There are monochrome 16-bit profiles back to v2, oddly.
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