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I notice the container has no ICC profile support. Trivial do add as an extension tag, but should definitely be in the first spec IMO. And if I read this correctly, extension tags are hardcoded as numbers, rather than using a tag name. I don't think that's a good idea.
What's needed is a compression method that doesn't introduce artifacts on hard edges, as JPEG does, but is otherwise no worse at compression than JPEG. Then we wouldn't need to do some things in JPEG and others in PNG, and we'd be spared the pain of JPEG screenshots. Much better results on the Tecnick image set (which is mostly hard edges) would indicate one had been found. The results only indicate modest improvement in that area.
Why not use Daala to start from? The overlapping transform probably help especially for still images, and the patent situation is probably at least better.
I really dig it, but I'm not yet familiar with BPG. It seems that decoding it would take more processing power, and potentially be slower than JPG. Is this the case? Under the "performance" section, decoding speed was not mentioned.
Yes, it's slower and takes more RAM than JPG. I can see a delay of about a second in my browser. (Edit: I assume my browser is caching the data, but if not, some of that time could be re-downloading the data.)
[0] http://people.mozilla.org/~josh/lossy_compressed_image_study...
Its purpose is to replace the JPEG image format when quality or file size is an issue. Some of the HEVC algorithms may be protected by patents in some countries There have been some patent disputes over JPEG, but I don't think replacing it with another possibly patented format is a good idea, even if it's technically superior in some ways.
"Most devices already include or will include hardware HEVC support, so we suggest to use it if patents are an issue." I don't know if that suggestion makes much sense, but you missed it in your quote.
Wow, I didn't even know there were open-source HEVC encoders. I thought there were patent issues. Now I'm off to re-encode my bluray collection!
The results only show marginal improvement. What's needed is a compression method that doesn't introduce artifacts on hard edges, as JPEG does, but is otherwise no worse at compression than JPEG. Then we wouldn't need to do some things in JPEG and others in PNG, and we'd be spared the pain of JPEG screenshots. Much better results on the Tecnick image set (which is mostly hard edges) would indicate one had been found.…
JPEG 2000? JPEG XR? Wavelets tend to produce softness instead of ringing or noise.
I appreciate the historical tradition of using the photo of beautiful young Lena Söderberg as a test image, but it's time to move on. It's fun for us hetero males, but like it or not, this sends a message to young women that they aren't welcome in this field. I wish Fabrice Bellard would have left them out of the demo set. Having said that, all those demo photos do look good. I was wondering how we were going to see…
If I were someone working on image compression techniques I would probably have seen many many algorithms and their output using that image so when I see a new algorithm and a new Lena, I might look at the results and think "Hey, this is similar to this other approach I am familiar with"
So many photos taken on any given day are photos of people, so it's simply not practical to eliminate a human subject from test images. If we're going to have an image of a human subject, that person is going to have to be somewhere on the gender spectrum. More data (images of two people) is preferable to no data (no images of people to avoid the risk of offending anyone)
Earlier quoted context omitted.
"Most devices already include or will include hardware HEVC support, so we suggest to use it if patents are an issue." I don't know if that suggestion makes much sense, but you missed it in your quote.
What kinds of devices have hardware HEVC acceleration? Phones, PC graphics cards, Blu-ray players?