[MPlayer-users] overlay safe zones

[Alexander Strasser]

Hi all!

On 2020-07-19 16:09 -0400, The Wanderer wrote:
> On 2020-07-19 at 14:49, muzzol wrote:
>
> > I need to monitor several streams and I would like to see safe
> > zones: https://eks.tv/wp-content/uploads/2018/09/Safe_Areas.jpg
> >
> > is there a way to overlay that on mplayer?
>
> For this, you want a video filter.
>
> The one I specifically remember for doing overlays, from when I was
> active in MPlayer, is 'bmovl', for 'bitmap overlay'. The man-page
> section on that filter doesn't look especially user-friendly
> (significantly less so than I thought I remembered from discussions back
> then, in fact), but it doesn't look impossible either.
>
> Googling for 'vf bmovl' (without quotes) finds pages such as
> https://www.linuxjournal.com/content/overlay-images-video-using-mplayer-and-mencoder,
> which provides a worked example of someone apparently using this in the
> real world (albeit apparently back in 2010).

Wow, the article behind that link seems to convey a sad story :/

But yes bmovl should be usable. I used surely used it myself,
a few years ago when fixing a bug.


> Searching the man page for 'overlay' also finds mention of the
> libavfilter filter named 'overlay', which is labeled as experimental and
> is apparently meant to overlay one video on top of another video; that
> doesn't look as suitable for what you're talking about, but something
> could probably be kludged together.

Using libavfilter overlay from MPlayer is currently not possible.
If you want to use it, you could process the video with ffmpeg
before displaying the video with mplayer.


> There might be more, but that's all I'm coming up with at the moment.

For the case at hand I would recommend to first try to use multiple
instances of the MPlayer video filter named rectangle. Should be a
cheap starter and maybe even sufficient.


Happy video filtering :)


Best regards,
  Alexander