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Mpv – A free, open-source, and cross-platform media player

(mpv.io)
1113 points Bluestein | 4 comments | 17 Aug 24 18:56 UTC | HN request time: 0.607s | source
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lairv ◴[17 Aug 24 21:38 UTC] No.41278203[source]▶
I use it to inspect video frames by frames, particularly being able to go back one frame. VLC doesn't support it, this thread about the feature is hilarious https://forum.videolan.org/viewtopic.php?t=120627
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sergiotapia ◴[17 Aug 24 22:06 UTC] No.41278382[source]▶
i wonder why he's such an ass about it, and totally adamant that it's impossible when multiple players already do this fast. ego?
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variadix ◴[17 Aug 24 22:49 UTC] No.41278658[source]▶
I think technically he’s correct (I haven’t worked on media decoding code, but I understand how common video encoding formats work). If you have a long video with only a single key frame at the beginning then to step back you would need to, starting from the beginning of the video, decode every frame up to the previous frame you wanted to jump to in order to apply frame deltas, also assuming you have some sort of frame counter to determine when you’ve reached the target frame. In the worst case this does require a lot of compute, but this is an edge case if you primarily care about common video formats with normal encoding settings. I assume seeking backwards is also painfully slow on videos encoded in this manner, so why stepping back 1 frame is out of the question when compared to seeking backwards, I don’t fully understand, it must have something to do with precise frame counts being unavailable on some hardware decoders for some formats (and there being no good workaround) so you _may_ not actually go back 1 frame.

I don’t see any reason it couldn’t be supported for a set of formats with reasonable encoding/decoding settings, and provide some error message for other formats if a user attempts to step back, e.g. reverse frame stepping unavailable for current video due to format/encoding/decoding settings.

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sergiotapia ◴[17 Aug 24 23:55 UTC] No.41279035[source]▶
that's still a whole lot of yapping that as an end user I don't care about. i can frame scrub forwards and backwards in multiple other apps. right? very weird response from the vlc team in that original thread.
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1. makeitdouble ◴[18 Aug 24 01:03 UTC] No.41279330[source]▶
The back and forth in itself feels so weird to me, with so many hurt feelings:

- the devs expressed in no uncertain terms that they don't want to do it (the first answer is just perfect)

- every third comment is about "we know you don't want to do it, but as users why should we care ?"

Well, if you don't care about the devs, on what base are you asking them to care about your specific problem ?

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2. justin66 ◴[18 Aug 24 03:33 UTC] No.41279947[source]▶
> Well, if you don't care about the devs, on what base are you asking them to care about your specific problem ?

Caring about the user's requirements is part of the dev's job description. Caring about the dev's... anything is not in the user's job description. (one advantage commercial software has: it really does help when there's an interface between the dev and the user in the form of customer support. or a commercial incentive to actually work on what the user wants.)

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3. skydhash ◴[18 Aug 24 04:08 UTC] No.41280060[source]▶
> Caring about the user's requirements is part of the dev's job description.

For OSS project, it's better to assume that the user persona for the software is the devs or the maintainers. The dev-user relationship you expect is actually the vendor-client in commercial software.

4. makeitdouble ◴[18 Aug 24 06:08 UTC] No.41280449[source]▶
> job description

Money getting involved would indeed simplify the question.

Here no money is changing hand, so coming up with an angle that's motivating enough for the devs is IMHO the only option. Either bring up an aspect they're not considering that changes the equation for them, or come up with a solution that isn't plaggued by the issues they are afraid to deal with.

That's where I see listening to the devs and caring about their issues to be the only path forward, short of contributing as a dev oneself..