FFmpeg Meeting VDD 2024
These are the meeting notes for the FFmpeg meeting at VDD2024 in Seoul on November 2nd 2024, 16:00 Korean Time (UTC+9). The meeting took place at Kwangwoon University (Saebit Building, Room 204) with 39 persons attending.
Topics
r_frame_rate
It is a stupid name, it should not exist.
Rename average_framerate
, should also be always a framerate not field rate.
r_frame_rate
is not an average framerate, the concept of a fundamental "minimal" frame/fieldrate is useful for lossless transcoding of timestamps. Maybe minimal_timebase
or fundamental_timebase
would be a better name.
Remove both r_frame_rate
and average_framerate
and introduce a new field called framerate
.
Swscale
How much do we want swscale to do what looks good vs. mathematically reversible and objective (like zscale). To what extend should it do perceptual mapping?
Concern: Perceptual mapping not reversible.
Support both, make non-perceptual the default for now.
MMX & up
Which SIMD to write to replace the MMX: SSSE3 minimum. If SSE2 exists, remove MMX, directly.
Dynamic Range Compression (DRC)
Specific for each codec. You might not want it for transcoding so it should be user-selectable for DRC passthrough. Needs a way to know what the final output will be.
New Codec/Muxers/Transports
- MPEG-H audio
- APAC (Apple Perceptual Audio Codec)
- AC-4
- BlackMagic Raw/ProRes Raw
- APV - https://datatracker.ietf.org/doc/draft-lim-apv/
- xHE-AAC part 2 (the return)
- e-RTMPv2
- MVC H.264 MultiView Coding
- WHIP? (requires WebRTC)
- NDI
- UltraHDR
I/O bound processes
API use for demuxing
libavio / libavdevice
Can we split libavio from libavformat? Yes, we can.
Should we? 9 vs 3 vs 20 (yes, no, abstain)
Reasons:
- I don't see the practical benefit of doing it.
- You could use it in libavcodec and libavfilter (it currently does it internally)
Can we split libavdevice from libavformat?
Should we?
Code Comments
YES. MOAR COMMENTS.
Subfolders
Less files directly under the main libavcodec/
folder.
AVSubtitles
PATCHES WELCOME.
Encryption + Packaging
Fully open-source, no blobs, no key management etc. JUST the packaging.
Deprecate sonicaudio
Ping Michael again, on that.
x265 experimental
Leaks, overreads, ABI breaks
Let's do the MCW talk.
Better Infrastructure document
- Overview of infra 'layout': https://git.videolan.org/?p=ffmpeg.git;a=blob;f=doc/infra.txt;h=30a85dd5ce97341664416926286d401ce4e73639;hb=HEAD
- Overview of people in 'Miscellaneous Areas': https://git.videolan.org/?p=ffmpeg.git;a=blob;f=MAINTAINERS;h=7ac5614c18dbc3a9b4b575de07d330cb00b0392d;hb=HEAD
GA Voting for roots access? 19 vs 0 vs 9 (yes, no, abstain)
Who controls mails? Who control Github FFmpeg?
Who controls DNS? Alexandre Strasser? ffmpeg.org / avcodec.org ?
Who controls FFmpeg security mailing list?
Policy about using the FFmpeg Name
IBC and so on are using the FFmpeg name
-> Trademark & Policy
Copy the Kodi policy
How do we do booths? -> Request to GA
Gitlab move
23 vs 0 vs 2
I want a GA vote, of proposal to use videolan gitlab; needs to be in partnership with someone from videolan who has full access.
'FFmpeg has its own infrastructure and that should be used'
Lynne says we should consider moving to Forgejo, because of Federations. Lynne should write a full proposal similar to the above.
Meson move
PATCHWELCOME?? (deciding on it is useless, it's like 'should we rewrite swscale') There was a patch. Old patch.
Vast majority of people don't really care about this question. Aka it's just technical, if it can be done well enough then it is okay.
Unconference topics
Topics skipped for FFmeeting.
- GitHub ASM Course
- New comers
- AVTransport
- Audio Resampling