[MPlayer-users] ass subtitles, vo gl and amd video

[Vladimir Mosgalin]

Hi Reimar Döffinger!

 On 2013.09.24 at 09:43:53 +0200, Reimar Döffinger wrote next:

> >I don't know of a way to force vf_ass-like rendering on mpv, so I only
> >checked default rendering with -vo opengl-hq - no performance problems
> >at all, but subtitles look quite a bit sharper than in mplayer. Idk
> >why,
> >but for some reason mplayer always renders subtitles in 1.ass blurry
> >for
> >me (not the case with other subtitles and 2.ass), while mpv renders
> >font
> >edges sharp, as they're (I think) supposed to be.
> 
> 1.ass and 2.ass are supposed to look exactly the same.
> I see exactly two possibilities:
> 1) (likely) I misunderstood how line-drawing clipping is supposed to work. The way 2.ass and mpv render is just wrong, and the reason for the performance difference.
> 2) libass implements the line drawing clipping wrongly. That should mean that mpv uses a different fork of libass than the one you tried with MPlayer.

Let's see, are we even seeing the same thing?

Here is how 1.ass looks in mplayer:
http://lime.hacked.jp/sub/mplayer-sub1.jpg
Here is how it mostly looks in mpv:
http://lime.hacked.jp/sub/mpv-sub1.jpg
except for glitch that happens sometimes:
http://lime.hacked.jp/sub/mpv-sub1-glitch.jpg

As you can see, mplayer renders subtitle way too blurry. Is it really
supposed to be like that?

Here is how 2.ass looks in mplayer
http://lime.hacked.jp/sub/mplayer-sub2.jpg
and mpv
http://lime.hacked.jp/sub/mpv-sub2.jpg

(it's mplayer built with git libass, but 0.10.1 looked the same)

There are more differences in rendering if using scale filter before ass
rendering or in fullscreen, but I'm unable to take screenshots of
either.. It was hard enough to take these screenshots as I had to do it
quite roundabout way and they still came out glitchy often (empty
windows, no subs, distortions, transparent subtitle parts replaced by
checkers pattern and so on).

-- 

Vladimir