Yes, it is. MPlayer is actively maintained, so your statement is a false one. slouchfuzz is absolutely right. The truth is that mpv has some cool features, which are not included in MPlayer. Even more: mpv has some cool features, which you will not find in VLC. But this does not mean that VLC is not actively maintained...

There might be a difference between actively maintained and actively developed.

Actually I never objected to his comment on MPlayer. If anything, my comment here is that mpv isn't really any more maintained than MPlayer is. They still function about the same at a high level.

Which are what?? dugan did suggest one that made sense; A-V sync which has been one of the historic problems and a motivation towards the forks. I forgot about this one and I can understand this suggestion. But I haven't had problems with A-V sync in MPlayer in more than 10 years, which also pre-dates its inclusion into slackware. Maybe this is hardware or driver related. Or it got fixed.

There must be a difference between the truth and the false

Sure, but who is the judge? (BTW, it is truth vs. lie, true vs. false.) In real life wars are started because both sides are right.

@the3dfxdude
I've already edited my post (Reason: mistake in copying forum member name). Sorry.

Cool mpv features? mpv is the best solution (I am aware of) for watching/streaming YouTube (and similar) videos. SMPlayer/SMTube makes use of this.

PS.
MPlayer has always been my favorite media player.

Wow! I give up...

MPlayer is actively developed (and maintained). They've released two versions just this year, 1.2.1 and 1.3.0. And 1.2.0 was released Oct of 2015.

MPlayer2 was originally forked from MPlayer to add extra features but ended up being abandoned. mpv was forked from the MPlayer2 source and continued their work under a new name.

mpv removed a lot of older stuff from MPlayer that the MPlayer developers refused to remove. This also includes mencoder. It is a leaner program, but doesn't have encoding capability (if you're interested in that). However, they also changed a lot of options and flags for commandline usage. While SMPlayer does work with mpv, the mpv developers do not recommend it. It can lead to unexpected bugs that are occasionally reported on mpv's Issues page on github that the mpv developers flag as "not our bug".

mpv does add features just as it removes others from MPlayer. I have been perfectly happy with MPlayer, and now that it is included in Slackware (and is fully and properly supported in SMPlayer), I see no need to do all the work of getting mpv compiled for what is probably very little actual perceived differences. MPlayer plays my videos fine, and until it doesn't, I see little benefit in switching.

You use ffmpeg or Handbrake to encode. The discontinuation of mencoder should be a non-issue. And if you really like mencoder, you can keep it installed for encoding while still using mpv for playback. The packages don't conflict.

FFMPEG is a dependency for mpv (whereas MPlayer just builds FFMPEG as part of its own source), so if you have mpv then you have FFMPEG.

Also: how's MPlayer's VA-API support these days? A standard build of mpv supports VA-API by default. It's great if you're using an Intel GPU.

Strictly speaking: FFmpeg is a dependency for both mpv and MPlayer (both can use FFmpeg shared libraries). Optionally, MPlayer can use statically linked FFmpeg libraries embedded in its executable.

Fair enough, maybe what I'm remembering was just referencing the removal of a specific command to encode stuff, or maybe encoding was completely removed and then was added back in. I'm really not sure since its been a while since I researched it. But the rest of my info is still valid. MPlayer, contrary to your posts, is still actively developed and maintained. MPlayer2 might be the one you're thinking of since this project is dead (and it is what mpv was forked from). This isn't to say it is better or worse than mpv, but your original argument of MPlayer not being actively developed is false. That was the only point in my post. MPlayer is still developed and has released two versions just this year. Now people can be better informed when deciding between the two.

Not a big deal for me. In the past, if I needed to encode, I've used other programs that are probably based on ffmpeg (it took me almost two years after my 14.1 install to find a need to compile ffmpeg and its dependencies).

I like not needing to build ffmpeg (and all its dependencies) to be able to play back video when I first install Slackware. In that matter, MPlayer is superior since it'll work out of the box on a full install. mpv might be a better video player, but it takes more effort to get it working on Slackware. If you need ffmpeg for other programs, then mpv is a good alternative, but if you don't need it, then it is a lot of effort for a player that may not make any noticeable difference on your system.

As far as I'm aware, the only "benefit" mpv offers me is the ability to play youtube videos from the commandline, but I am perfectly content playing them with the browser, so that isn't a worthwhile feature for me.

But from research, it seems mpv is a superior video player, I just don't find any inadequacies with MPlayer that mpv fixes, so I haven't found a need to try a different player.

Can't comment on this since I don't have Intel hardware.

So what is new with new MPlayer? Is this active development adding any features? Or just bugfixes?

BTW, compiling mpv takes just 32.8 s on my i3. Resulting binary is 1.3 MiB.

It's compiling FFMPEG that's the timesink.

According to their website's main page, 1.3 provides:

Unfortunately, I couldn't find a web-browseable view of their svn repo, so I don't know how much development is occurring. But, a good chunk of the MPlayer developers are also ffmpeg developers.

Try doing that on a fresh Slackware install and see how long it takes you to get mpv compiled. It will fail and then you'll need to start looking into the dependencies of mpv. Once you factor in all the dependencies, it can take quite a while just to be able to do what MPlayer can do when you first boot up a fresh install. When I build ffmpeg, I will include all the formats I might possibly need so I don't need to recompile it in the future just to add something. Add to the fact that ffmpeg doesn't support autodetection for a lot of the optional dependencies, you then have to play with the SlackBuild (or manually dig through the ./configure --help output) to find out what you need to pass in order to enable support for your desired formats.

As I've already said, I'm not arguing which one is better than the other. But MPlayer is supported out of the box and does pretty much everything most people want out of a video player. mpv requires a lot of extra work to get up and running on Slackware. For some, it is worth that extra work, for others, it isn't.