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

mpv.io

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

#111

Post by variadix »

sergiotapia wrote: post #83
lairv wrote: post #69

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

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?

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.

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

#112

Post by asveikau »

aaplok wrote: post #99
efilife wrote: post #94

Earlier quoted context omitted.

> It is interesting that nobody in the thread went to check in the code of mpv, smplayer, etc. to see how it's done there. Surely this would be the best response to his request for technical suggestions? Maybe because these users just can't code?

> Maybe because these users just can't code? It would be still interesting that the intersection between the set of users who claim on this forum it's possible and the set of users who can code is empty.

I haven't looked into any claims or followed these links, so I don't know what the limitation is.

But abstractly, it's absolutely possible to write a program that decodes frame at a time and displays them slowly.

Now, whether there is some architectural difficulty based on design decisions within their player, or any player, I don't know.

Edit: I guess downvoters have never worked with a video decoder api before? I just read the link and it seems like the rationale is to not seek one frame backwards because you'd have to seek to a key frame and waste some work? That's not the same as it not being possible.

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

#113

Post by 0cf8612b2e1e »

mixmastamyk wrote: post #39
Bluestein wrote: post #14

Earlier quoted context omitted.

> There have files I’ve encountered that for example VLC will play with quirks (color reproduction is not quite right, etc) that mpv plays perfectly. Given how VLC is basically bulletproof and will play absolutely anything thrown at it - it's great to hear that mpv is up there ...

While great in general, vlc has many small seek/sync issues, and also seems to be in maintenance mode.

What non-maintenance work needs doing? From the outside, it plays basically all the formats. There is always the potential for improving algorithms, but it strikes me as pretty feature complete.

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

#115

Post by SSLy »

loeg wrote: post #88
jwells89 wrote: post #5

This has always worked well for me, handling anything that’s thrown at it with ease. Things may have changed since then, but when I first encountered the project several years ago it seemed like the thing that made this project stand out compared to other player projects was a big emphasis on correctness and accurate playback. There have files I’ve encountered that for example VLC will play with quirks (color reprodu…

Hm, I've had (significant) issues with color representation playing back "HDR" media in mpv.

was the material purple-green by chance?

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

#116

Post by pentagrama »

arp242 wrote: post #66
pentagrama wrote: post #60

Happy VLC user here, but might give this a try, I want to find a better UX with the player controls, like a way to pin the controls bar when full screen (it disappears after some seconds), a 10s forward/backwards control, bigger buttons, less bloated settings, less features that I don't use like radio and other stuff. But one thing that confused me seeing that homepage is that it shows a player UI screenshot, but it…

mpv has a UI for things like seeking forward and backward, displaying info, etc. But you typically start it like: % mpv file.mp4 That's what they mean. It doesn't really have things such as "File → Open" like VLC has. At least not out of the box, but it's scriptable with Lua and there are scripts and even entire "alternative frontends" that can do this. It can also be remote controlled via a socket; I built an audio…

Thanks for your response. Understand. So MPV may not be for me, I don't know how to use a command line app, I remember have to use to fix an Ubuntu issue and the UX was painful to me.

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

#117

Post by SSLy »

radicality wrote: post #53
tbeseda wrote: post #48

If anyone is looking for the mpv core with a GUI on macOS, take a look at IINA https://github.com/iina/iina

It’s also the only way I can play HDR on macOS that looks decent (besides the native players like QuickLook/Quicktime/Photos). I went into a rabbit hole recently playing iPhone-recorded Dolby hdr videos and tweaking all the various mpv settings but nothing really looked the same as in Photos. Iina is closer but also not exactly the same as the native players.

infuse will also do good job, but it's using apple engine instead of ffmpeg, and it's paid for the good stuff https://apps.apple.com/us/app/infuse-video-player/id11362209...

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

#118

Post by j1elo »

lairv wrote: post #69

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

Wow those answers are indeed funny. I agree that as an OSS dev/maintainer, it's easy to fall on the vice of over-generalization and crusade for the perfect solution, and it feels that's exactly what happened there.

> this feature is algorithmically impossible

> You're just looking at one specific video, not the general problem.

> is not generally possible.

As a fellow multimedia dev, man, who cares? Sometimes we forget that software ought to be useful, not hypothetical ideals of truth. Just implement the feature for those codecs that support it and which probably are in the 98% percentile of what users actually use, regardless of the damned "general case".

Or accept and announce shamelessly that you don't have either the knowledge or the development resources to tackle such a complex feature. But excuses about not being possible for absolutely every possible codec in a completely generic way is just denying that the world is just a chaotic and dirty place where things are not ideal nor perfect. Just give your users a real-world solution (or rejection).

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

#119

Post by SSLy »

pentagrama wrote: post #60

Happy VLC user here, but might give this a try, I want to find a better UX with the player controls, like a way to pin the controls bar when full screen (it disappears after some seconds), a 10s forward/backwards control, bigger buttons, less bloated settings, less features that I don't use like radio and other stuff. But one thing that confused me seeing that homepage is that it shows a player UI screenshot, but it…

you can just drag-n-drop a file on top of the window and it'll promptly get played

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

#120

Post by SSLy »

causality0 wrote: post #57
adamomada wrote: post #56

Mac users can get a very nice front end to mpv with https://iina.io Bonus trivia: Plex Media Player uses mpv as the video player

That is... not a glowing endorsement. I've had more bugs and player failures from Plex than any other media software I've ever used.

plex uses terribly old build of mpv with questionable config
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