Author Topic: x264 metadata  (Read 3552 times)

Offline Anakunda

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x264 metadata
« on: September 24, 2011, 01:52:08 AM »
Hello having 2 questions about x264 metadata:

1. Sometimes x264 output consequently muxed by mkvmerge contains in [Video] section field about average bitrate, sometimes not. I wanted to ask on what conditions depends presence of this metafield and how can I force to final container always containing metafield about average (and possibly peak) bitrate. This conserns cases when video is made in variable bitrate mode.
2. Is there a way to add a tag with custom name and value to x264 output, that couldnot be easily altered or removed by rebuilding with Mkv toolnix?

Thank U for answering 8)

Offline J_Darnley

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Re: x264 metadata
« Reply #1 on: September 24, 2011, 02:44:19 AM »
The only metadata x264 adds is the encoding settings string.  If you want "hard"-to-remove metadata you had better use the x264 API and add you own custom SEI (if I correctly remember that feature existing).
Knowledgeable about: cmd.exe, ffmpeg, x264

Offline Anakunda

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Re: x264 metadata
« Reply #2 on: September 24, 2011, 05:57:46 AM »
So there is a 3rd party tool that is able to "hard-inject" custom metadata into h264 track, or edit the metadata completely the same way like mp3 taggers work ?

Offline Selur

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Re: x264 metadata
« Reply #3 on: September 25, 2011, 02:01:20 AM »
No, at least there's no known tool (aside from a hex editor) to change the metadata.

Offline Anakunda

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Re: x264 metadata
« Reply #4 on: September 25, 2011, 02:07:23 AM »
So customizing x264 source is the only way to add custom metadata tag? If so, is there already some existing mod of this encoder that supports adding custom metadata?

Offline Selur

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Re: x264 metadata
« Reply #5 on: September 25, 2011, 02:32:01 AM »
afaik no, nobody really cared enough about it to write such a mod and share it with the public.
Most people use container tags to add their personalized tags&co.

Offline Anakunda

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Re: x264 metadata
« Reply #6 on: September 25, 2011, 03:31:22 AM »
Thanks. Yet I need to elucidate the mystery about conditional Bitrate field. How do I force x264 (or mkv merge?) to write avg (and peak) bitrate to final container. I see often h264 videos encodde with x264 in variable mode and having the Bit rate field present in its metadata (this is shown by Media info).

Offline Selur

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Re: x264 metadata
« Reply #7 on: September 25, 2011, 03:41:12 AM »
You will probably have to look at the sources and see when x264 inserts this specific field to the metadata,.. ;)