BPG Image Format (HEVC subset for browsers)

[djcj]

Was anyone able to build the javascript decoders from source? I can't get that to work on Linux (might be relevant for distribution packaging once a stable release comes out).

[easyfab]

Originally Posted by xooyoozoo

As the default method to to get bpgenc to produce animations is really really frustrating, I eked out a "bpgmux" of sorts in my modded libbpg.

The muxer will be quite verbal if it sees something it dislikes, but most x265 encodes with

--ref 1 --bframes 0 --rect --amp

will work.

Could you give me an example that work for you.
I try multiples files ( only files < 3 frames works )
for example : x265 foreman.y4m -o foreman.hevc --amp --rect --ref 1 --bframes 0

and I always have this :
bpgmux.exe foreman.hevc -o foreman.bpg
too many neg (2) or pos (0) refs
error while parsing (alpha? 0) NALs
Error while building modified hevc buffer with 2 frames processed
Muxing has failed.

[xooyoozoo]

I originally couldn't reproduce your issue, but then I remembered that I've been using a locally "fixed" (see bug report) build of x265.

Apparently without the patch, x265 is counting the single ref frame twice. I'm not sure why x265 does this, especially as the behavior is unrelated to weighted pred, but decoders are usually based on uniqueness, so no harm no foul.

I just committed an allowance for this into the muxer.

[easyfab]

Thank you xooyoozoo.
I confirm it work now and a lot easier and faster than with bpg

foreman:
gif 9.43 Mo and bad quality ( with ffmpeg )
x265/bpg 497 ko ( crf23)

Animated bpg should soon rules

[Nintendo Maniac 64]

Any new comparisons with Daala? A new presentation video claims they're better than x265 in texture details and, when above 1bit per pixel, also on clean edges.

[Zero3K]

Is there any BPG viewer that is small in size? If not, one should be made. Thanks in advance.

EDIT: Is it possible to convert animated GIFs to BPGs? If so, how?

[benwaggoner]

Originally Posted by Nintendo Maniac 64

Any new comparisons with Daala? A new presentation video claims they're better than x265 in texture details and, when above 1bit per pixel, also on clean edges.

Above 1 bpp seems like a questionable requirement.

x265 doesn't have a --tune stillimage equivalent yet, which would be the proper comparison point. Although I've had some success in early experience by copying the equivalent x264 parameters over.

[djcj]

I was able to use the GNU automake system to build libbpg: https://github.com/darealshinji/libbpg/tree/automake
You can link bpgenc just to x265 without building jctvc if you want, you can build a shared library (will be named libbpg-version.so.0 since there's no official libbpg.so.0 yet) and simple manpages will be generated. A pkg-config file will be created too.
The javascript libraries aren't generated yet (use Makefile-original for that).

By the way kvazaar is now licensed under LGPL which might be a good opportunity to enable it as an encoder: https://github.com/ultravideo/kvazaar

[Nintendo Maniac 64]

Originally Posted by benwaggoner

Above 1 bpp seems like a questionable requirement.

I'm just reporting what was said in a recent presentation on Daala. I believe the 1bpp thing just happens to be where the threshold of bitrate where they cross.

[birdie]

Lossless WEBP heavily beats lossless BPG.

In my case we're talking about 12% difference in resulting file sizes which is kinda weird since VP8 is not nearly as advanced as H.265.

I'm testing just one image but I still didn't expect such a result. I thought BPG would be a clear winner or at least there would be a tie.

[Skarstorm]

Why are you talking about lossless compression?

[mandarinka]

Originally Posted by ApTeM

Lossless WEBP heavily beats lossless BPG.

In my case we're talking about 12% difference in resulting file sizes which is kinda weird since VP8 is not nearly as advanced as H.265.

That could be because lossless WebP isn't really VP8, it uses custom encoder and format with various additions and special tools to improve lossless intra compression.

[benwaggoner]

Originally Posted by mandarinka

That could be because lossless WebP isn't really VP8, it uses custom encoder and format with various additions and special tools to improve lossless intra compression.

That's still a surprising result. Do you have details for the specific image and settings used? A 12% delta is HUGE with lossless compression.

Some of the standard images used in J2K v. JPEG evaluation would be interesting, since there are already data points for other image codecs. I'm most interested in natural images (non-synthetic) myself. I know HEVC is getting some improvements for screen capture and that sort of content.

it might also be interesting to see how the latest version of x265 compare. Although I'd expect relatively small version-on-version improvements since rate control and interframe compression don't apply to still image encoding.

HEVC's intra-frame prediction should be a big differentiator from past codecs for still frame encoding in general, including (but probably to a lesser degree) lossless.

[Tommy Carrot]

Originally Posted by ApTeM

Lossless WEBP heavily beats lossless BPG.

In my case we're talking about 12% difference in resulting file sizes which is kinda weird since VP8 is not nearly as advanced as H.265.

I'm testing just one image but I still didn't expect such a result. I thought BPG would be a clear winner or at least there would be a tie.

Did you use x265 or the reference encoder for lossless encoding? Because the latter is massively better for lossless compression, probably because x265 doesn't support the recently added features of the h.265 standard, which are improving the lossless efficiency quite significantly.

[birdie]

I used the reference BPG encoder ( http://bellard.org/bpg/ ) using maximum compression (-m 9).

Here are the source files if anyone's interested.

These are three pictures stitched together and the difference is 7%. When I make a collage containing over 50 images (I cannot post the others, sorry), there's 12% difference. What's even funnier is that zip manages to compress WEBP files (2% is like nothing but anyways), while BPG files are incompressible.

[foxyshadis]

The latest XnView MP beta claims to support bpg. I haven't had time to test it yet, but it's a start.

[Tommy Carrot]

Originally Posted by ApTeM

I used the reference BPG encoder ( http://bellard.org/bpg/ ) using maximum compression (-m 9).

Here are the source files if anyone's interested.

These are three pictures stitched together and the difference is 7%. When I make a collage containing over 50 images (I cannot post the others, sorry), there's 12% difference. What's even funnier is that zip manages to compress WEBP files (2% is like nothing but anyways), while BPG files are incompressible.

I'm not really sure why it performs so relatively badly, BPG with the ref encoder compresses your image barely any better than PNG does, even though on most images i've tried it it's at least 10-20% more efficient. Possible reason could be that your image is very blurry with very little spatial detail, and HEVC lossless mode is not really optimized for such circumstances.

I've tried x265 on your image too, it compressed it to 818533 bytes, which is even worse by 30%.

[birdie]

So far H.265 is full of myths while IRL it performs worse (at least at high bitrates when the details are paramount) than the x264 encoder based on H.264.

[benwaggoner]

Originally Posted by ApTeM

So far H.265 is full of myths while IRL it performs worse (at least at high bitrates when the details are paramount) than the x264 encoder based on H.264.

For still images? And current builds?



Please share your settings and sources



Edit: Sorry, you linked tour sources above. I'll try to take a swing with a current x265 build.

[birdie]

I used the latest available BPG release.

I didn't use any fancy settings other than -m 9 (maximum compression).