xvc - a next-generation video codec at xvc.io

[jonatans]

Originally Posted by Gravitator

xvc v2.0 2018-09-23 #d3e8b46

There is no "-explicit-encoder-settings "aqp_strength 16"" ?

In xvc, internal encoder settings (settings that control how decisions and evaluations are made in the encoder) are exposed via the "-explicit-encoder-settings" cli parameter. These settings are primarily intended for development purposes and are not intended to be modified by the user and that is why this setting is not shown in the printout.

The full list of settings that can be modified by the "-explicit-encoder-settings" parameter can be found in the ParseExplicitSettings function in encoder_settings.cc.

We used this setting to generate the encode for our online demo (at https://www.divideon.com/products-an...ming-with-xvc/) as described in https://forum.doom9.org/showthread.p...72#post1832272. This was done in order to more closely meet the bitrate target. The difference in bitrate between two "-qp" steps are typically in the order of 12% so aqp_strength can be used to generate bitrate points in between.

[Gravitator]

Originally Posted by jonatans

Sounds interesting but it's not something we have looked in to. Is this a capability that is available for any other codecs in ffmpeg? Can you provide an example?

Привет!
I have a 50% load of coding can suddenly jump into 100% (the system squeaks) for a long time, then go back to 50%.
A pause can give: a breather, give a use for other heavy programs, it is possible that it will allow back to reduce the load (there may be a conflict of processes, or is it a feature of the coder's floating load ...).
Or we can wait for separate scripts, GUI with a pause.

[jonatans]

Originally Posted by Gravitator

Привет!
I have a 50% load of coding can suddenly jump into 100% (the system squeaks) for a long time, then go back to 50%.
A pause can give: a breather, give a use for other heavy programs, it is possible that it will allow back to reduce the load (there may be a conflict of processes, or is it a feature of the coder's floating load ...).
Or we can wait for separate scripts, GUI with a pause.

I see. The mutlithreading in the xvc software is so far entirely based on picture-level parallelism and it will encode as many pictures as it can in parallel, as long as they don't depend on each other. The prediction structure of reference pictures will cause the processor load to sometimes go down while waiting for new reference pictures to be completed.

If you want to ensure that your processor load never reaches 100% you can set the -threads parameter to a value that is lower than the number of cores available on your system. But this will of course also increase the encoding time somewhat.

[foxyshadis]

Originally Posted by Gravitator

Can you add the ability to pause xvc coding in ffmpeg?

Are you on Windows? Just press the pause key in the command window and FFmpeg will stop feeding the encoder frames until you press it again.

Pausing happens through the application ideally, not individual codecs inside of it.

[Gravitator]

Originally Posted by foxyshadis

Are you on Windows?

Win10x64

Originally Posted by foxyshadis

Just press the pause key in the command window and FFmpeg will stop feeding the encoder frames until you press it again.

There is no reaction to pressing the Pause key.

[Vin]

XVC is simply the best codec right now. Able to beat HEVC and AV1. But the real question. Is there a chance that the codec is going to actually be usable for anything other than just testing any time soon? Browser support, player support?
Any kind of hope?

[Selur]

decoding support in ffmpeg/libav would be great

[nevcairiel]

If you want widespread decode support, there should be a royalty free license for decoding-only. Let content distribution pay the bills.

But there also is no content, and without getting any major content distributor on board it's mostly irrelevant anyway.

[hajj_3]

Originally Posted by Vin

XVC is simply the best codec right now. Able to beat HEVC and AV1. But the real question. Is there a chance that the codec is going to actually be usable for anything other than just testing any time soon? Browser support, player support?
Any kind of hope?

H.266/VVC is due to be ratified in October 2020, that will provide a large compression advantage over AV1. If the creator of XVC wants to make some money then he should patent any tools that are great that he has created then submit those tools to the MPEG-LA for inclusion in the H.266/VVC standard. He could earn a decent amount from that and a lot of people would benefit due to how widespread the codec will be.

[iwod]

Originally Posted by hajj_3

H.266/VVC is due to be ratified in October 2020, that will provide a large compression advantage over AV1. If the creator of XVC wants to make some money then he should patent any tools that are great that he has created then submit those tools to the MPEG-LA for inclusion in the H.266/VVC standard. He could earn a decent amount from that and a lot of people would benefit due to how widespread the codec will be.

I think many part of xvc are what VVC will be, so it is like a head start into a commercial implementation.

[Gravitator]

Have a fresh build? And advise good settings for encoding in the 8000kbit/s range (Park_Joy).

[jonatans]

Fresh build of xvc for Windows x64 here: https://drive.google.com/file/d/1MOZ...ew?usp=sharing

Let me know if you would like a build for a different platform (or if you would like to use ffmpeg with xvc support instead).

For Park_Joy, 8 mbps you should probably be using around QP 27 for 720p and QP 30 for 1080p.

I would suggest -speed-mode 2 if you want the result reasonably fast, or -speed-mode 1 if you want the highest quality.

Example command line:
xvcenc.exe -input-file park_joy_420_720p50.y4m -speed-mode 2 -qp 27 -threads 16 -rec-file rec.y4m -output-file enc.xvc -verbose 1

Took around 30 minutes to encode on my laptop and gave bitrate of 7.7 mbps.

[Gravitator]

And the modified ffmpeg?

[jonatans]

Fresh ffmpeg with xvc support: https://drive.google.com/file/d/1Ywu...ew?usp=sharing

Example command line:
ffmpeg.exe -i park_joy_420_720p50.y4m -c:v libxvc -speed-mode 2 -qp 27 -threads 16 enc.mp4

[Gravitator]

Correct...

-speed-mode <0..2>
0: Placebo
1: Slow (default)
2: Fast
3: Faster
----------------------------------
Add the build number to the info field?

[kanaka]

Is any tool to repack file.xvc do file.mp4 and file.mp4 to file.xvc?

[LigH]

The MP4 container will probably not accept xvc content officially, it has relatively strict specifications. The ffmpeg linked above by jonatans may do so due to a high similarity to other MPEG video content formats. (Please note the difference between a container format and a content format; .mp4 is a container, .xvc is a raw video content stream.)

It's more likely that MKV may accept xvc content some day, but check their changelogs if a current version does. Version 30.1.0 "Forever And More" (2019-01-05) did not yet announce that in their docs/NEWS.txt of the MKVtoolnixGUI installation.

Disclaimer: Statements above are my humble opinions, I may be wrong.

[kanaka]

Originally Posted by LigH

Please note the difference between a container format and a content format; .mp4 is a container, .xvc is a raw video content stream

I know difference, but I have script playxvc.bat

xvcdec.exe -bitstream-file %1 -output-file - | mpv.exe -

Dblclick on xvc file play this file in mpv. I cant do this with mp4 file.

[kanaka]

I've made tests of this codec (version from git, 18 january). It seems that xvc codec dont keep the same quality.

http://screenshotcomparison.com/comparison/128501

av1 q 36 vs xvc q 30 (and still too much blur). Other movies was acceptable.
I can't compare size becouse encoding was interrupted

[LigH]

Well, yes ... playxvc.bat uses xvcdec to decode *.xvc to an intermediate format mpv recognizes immediately. I would assume Y4M. But if you have an xvc video stream multiplexed in an MP4 container, xvcdec won't recognize the xvc video content stream inside the MP4 container. You would have to demultiplex it from the MP4 first, then decode the raw xvc content, and then forward it to the player ... very complicated.

Instead, use the ffplay inside ffmpeg_xvc20190121.zip provided by jonathans.