[mythtv-users] OSD glitch - starts as 4:3 and corrects to 16:9

Dave dave at 0bits.com
Sat May 26 21:09:06 UTC 2007

Mark Kendall mark.kendall at gmail.com said:
 > For standard xvideo display, mythtv creates the osd the same size as
 > the video frame size. It then blends the two together when necessary.
 > The video card then resizes the combined frame to the correct
 > dimensions for your display/source combination and displays it.

So i'm correct, for any source we're resizing twice:

1. OSD resized to TV source size
2. Combined frame (including OSD) resized (generally expanded) to X11 size.

this double resizing is what i'm having the problem with and is what is 
giving ugly fonts. Why are we not overlaying the OSD onto X11 directly 
and not the video stream ? Bear with me here. On my laptop for example i 
can start a video using mplayer/xine/vlc etc and using the appropriate 
key resize to full screen the size of my X11 display. Now with xosd (ok 
i know it's not antialiased or using TTF fonts but it serves my point) i 
can then write whatever onto the screen and it is independent of the 
video stream. It's written directly onto the screen at my desired 
location whilst the video is playing full screen or reduced. Try this

echo This is a test | osd_cat -i 100 -o 100 -f 10x20

So either i'm being completely dumb (which is more likely than not) or 
mythtv is flawed.

I'l like to get some time to try James suggestion of using the 
mythtv-vid branch, but it seems you are not quite convinced as per your 
followup query to him.

 > If you're getting poor fonts, first try a different osd theme and/or a
 > different font. Even with standard xvideo rendering at 1360x768, the
 > fonts still look pretty good.

I have tried various options, so i'd beg to differ here. Where i am, 
some of my channels on SDTV is transmitting at VCD quality and the fonts 
are completely unreadable. Have you tried viewing text written at 
352x288 and then expanded to 1360x768 ?

 > As I understand it, we only have one xvideo overlay to use at a time.
 > Hence we need to use the same one for both video and osd - so if we
 > want the hardware acceleration that comes with xvideo, we need the osd
 > at the video resolution.

So how do the standalone players (mentioned above) do it  ? Once i get 
back home i will try using xosd to see if can write text to a fixed 
location and size that is overlaid onto my SDTV video and return back to 
the group.

Thanks for the feedback though.

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