FFmpeg dealing with a security researcher

Kostya (ex-FFmpeg developer)'s take on the behaviour of the FFmpeg twitter account: https://codecs.multimedia.cx/2025/11/ffpropaganda/

He sounds bitter.

it’s very… sad, i guess, watching a lot of software engineering discourse on social media (at least, what I see from Twitter) just become this attention grabbing shitposting. ffmpeg is very much a big player in this field, and it has paid off handsomely - those tweets are often popular on site, and shared across other social media.

Wow these people have a lot of free time... shouldn't they be programming?

> paid off handsomely

Paid off how? Did they get more funding? More contributors?

The most interesting part of that is the admission that they used decompilers to reverse engineer the codecs. I wonder if makign that output freely available is legal.

"exposure"

I'm not sure if Kostya's account is truthful. He has a huge axe to grind against ffmpeg https://blog.pkh.me/p/13-the-ffmpeg-libav-situation.html

IIRC, his "LibAV" fork was malicious and his people lied a lot to the community ("ffmpeg is now deprecated!"). Ultimately, they failed, but I see a lot of their rhetoric and resentment in Kostya's post today.

Reverse engineering for interoperability is generally legal. Even if not, copyright does not follow the "fruit of the poisoned tree" idea, so if the new code isn't substantially similar to the original, it doesn't matter.

This isn't my place to argue, and certainly he was involved at the time, but LibAV wasn't really "his fork". Reading the full list of names who signed off https://lwn.net/Articles/423703/ I'm more interested in some other names, including darkshikari's deadname and the other heavy hitters of x264.

And if you browse through the ffmpeg mailing list of that historic month https://ffmpeg.org/pipermail/ffmpeg-devel/2011-January/ you'll find his name mostly attached to esoteric video game format patches and not in the big flamewar threads.

Actually - it looks like you can also see in that same month, his post of the first SMUSH codec implementation, that we're discussing in this thread. That's probably a bigger emotional factor than LibAV.

Kostya fanned the flames https://codecs.multimedia.cx/2011/10/why-ffmpeg-is-better-th... As for "his" ownership, I think LibAV was a failure each team member should own and comes to terms with.

That's my point and also why I won't dig more. The author hasn't come to terms with his bad experience with ffmpeg, in LibAV or otherwise. Whatever the baggage is, it feels quite messy and heavy. It weighs down the article, with too much bitterness and resentment. That could work for self-therapy, less so for a credible account. As he confesses at the end:

> I wrote this post with an ulterior motive—I don’t want to feel shame when remembering that I took part in that project. So far though the more I hear about it the more disgusted I become.