alt Hacker News> have limited control over their encode pipeline.
Frustratingly this seems common in many video encoding technologies. The code is opaque, often has special kernel, GPU and hardware interfaces which are often closed source, and by the time you get to the user API (native or browser) it seems all knobs have been abstracted away and simple things like choosing which frame to use as a keyframe are impossible to do.
I had what I thought was a simple usecase for a video codec - I needed to encode two 30 frame videos as small as possible, and I knew the first 15 frames were common between the videos so I wouldn't need to encode that twice.
I couldn't find a single video codec which could do that without extensive internal surgery to save all internal state after the 15th frame.
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> I couldn't find a single video codec which could do that without extensive internal surgery to save all internal state after the 15th frame.
fork()? :-)
But most software, video codec or not, simply isn't written to serialize its state at arbitrary points. Why would it?
I'm on a media engineering team and agree that applying the tech to a new use case often involves people with deep expertise spending a lot of time in the code.
I'd guess there are fewer media/codec engineers around today than there were web developers in 2006. In 2006, Gmail existed, but today's client- and server-side frameworks did not. It was a major bespoke lift to do many things which are "hello world" demos with a modern framework in 2025.
It'd be nice to have more flexible, orthogonal and adaptable interfaces to a lot of this tech, but I don't think the demand for it reaches critical mass.
I wonder if we could scan / test / dig these hidden features somehow ; like in a scrapping / fuzz fashion
A 15 frame min anf max GOP size would do the trick, then you'd get two 15 frame GOPs. Each GOP can be concatenated with another GOP with the same properties (resolution, format, etc) as if they were independent streams. So there is actually a way to do this. This is how video splitting and joining without re encoding works, at GOP boundary.