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BPG Image format

bellard.org

71–80 of 339 posts

Re: BPG Image format

#71

EDIT: I didn't expect this comment to be so popular and feel like I've hijacked the thread a little - sorry. Feel free to continue at https://news.ycombinator.com/item?id=8706850 I would much rather someone revived the Fractal Image format, which is now out of patent. It's very expensive to encode, but that's nowhere near as big a problem as it used to be. It's very fast to decode, very small, and the files are resol…

The following paper explains many of the reasons that engineers lost interest in fractal image compression: http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=660992...

Unfortunately I can't find a free PDF at the moment.

Re: BPG Image format

#72
post #18

I was ready to pass by this post with a yawn until I saw where it was coming from: Fabrice Bellard. He's no doubt an absolute freakin' genius. And if anybody knows about image conversion, it's him. Even the things he does just for fun are impressive. Have you ever booted up Linux inside your browser? http://bellard.org/jslinux/

100% agree with you, and in fact, as a proof, I didn't even know about Javascript Linux and I'm going to check it now :)

Re: BPG Image format

#73
post #15
post #10

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?

One of Samsung's cameras, iPhone 6 uses it for FaceTime, various 4k TV's.

Re: BPG Image format

#74
Impressive! Right now it requires a .js decoder, of 75kb.

Assuming a fast C++ decoder instead,(possibly GPU accelerated if the decoding algorithm is well suited for it) and not using JS but what would be the rendering times?

PNG are 4x bigger in his experiments, but interlaced PNG makes it more pleasant to users since it can be rendered progressively, can BPG benefit from such a thing?

edit: Interlacing is also used in JPEG, isn't it ?

It's a tradeoff, as a user, it's obvisouly a win situation when we have a low bandwidth, and as a server it's obviously a win.

Re: BPG Image format

#75
post #22

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.…

The results only show marginal improvement.

The improvement is far from marginal. In particular:

... I just tried to link you to a BPG image, and discovered that I can't.

Well, I'm going to ignore that little flaw for the moment, because that's just a browser feature. If BPG catches on, that's sure to change.

Anyway, the improvement is far from marginal: http://a.pomf.se/cdywsc.png

In particular, look around her face, eyes, and the background. The JPG is not just worse, but in fact very worse.

A more serious flaw is that it doesn't support animation. It doesn't need to be a video format. It just needs to be able to play a sequence of frames in succession. This is as easy as including a header that specifies how many frames are in the animation and the duration of each frame, followed by the image data itself. The fact that PNG doesn't have this has plagued the format since the internet became popular.

That may seem like "a video format," but it's not. Video decoders optimize for inter-frame compression, not intra-frame compression, so it's a different problem altogether. BPG doesn't need to do everything, but it should probably have basic animation.

Re: BPG Image format

#76
post #8

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!

There are still patent issues, and you still need to obtain a license to use the software. You will never see this image format integrated into any other open source projects, like Firefox, for this reason.

Re: BPG Image format

#77
post #19

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…

I think people that pretend to be offended by things like this, unwittingly infantilizing the people that they are trying to support, do far more to discourage minorities from tech than pictures of women's faces.

Re: BPG Image format

#78
post #2

Don't we already have WebP?

From the article: "Mozilla did a study of various lossy compressed image formats. HEVC (hence BPG) was a clear winner by a wide margin. BPG files are actually a little smaller than raw HEVC files because the BPG header is smaller than the corresponding HEVC header." This study includes WebP.

But he conveniently excluded webp from his comparison shots :)

Re: BPG Image format

#79

EDIT: I didn't expect this comment to be so popular and feel like I've hijacked the thread a little - sorry. Feel free to continue at https://news.ycombinator.com/item?id=8706850 I would much rather someone revived the Fractal Image format, which is now out of patent. It's very expensive to encode, but that's nowhere near as big a problem as it used to be. It's very fast to decode, very small, and the files are resol…

I tried something simpler than but similar to fractal compression earlier this year. Got interesting results:

http://pointersgonewild.com/2014/01/02/tile-based-image-comp...

Re: BPG Image format

#80
post #19

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…

Not everything is about gender, sexism, feminism, or chauvinism. There are very few things in the world that are not somehow associated with male vs. female in an objectively equal way. The Lena in question is just an image with a long tradition. Anyone can find and use a male image for his/her own image compression tests if s/he wants to. It's not a statement to use Lena instead.
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