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

[Mark Kendall]

On 5/26/07, Dave <dave at 0bits.com> wrote:
> Hi
>
> i posted a while ago about the OSD resizing and how in SDTV i get ugly
> fonts, but the responses still seem unsatisfying to me. So can someone
> clarify or correct the following:
>
> If i understand it correctly, the way it has been designed is that the
> OSD is injected/multiplexed into a dummy video stream of the size of the
> TV transmission and then resized to the default X11 screen size thus
> giving you ridiculously awful OSD when watching or switching to SDTV.

Ignore the piece about the dummy stream - it's a red herring here.

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.

> Even at DVD quality TV transmission (720x576) i'm getting jaggy OSD
> fonts. So for example on my Sony Bravia at WideXGA (1360x768) and X11
> running at the same size, then the OSD is created at 720x576 or some
> other even lower SDTV resolution and injected on a dummy Nupple Video
> stream at that size and then resized to fill the X11 screen.

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.

> Can someone explain why this design ? Why isn't the OSD multiplexed onto
> the video stream at the X11 size so it is always a fixed known size and
> not being resized at the TV stream size and then resized again to fill
> the X11 size ? I'm 100% sure there is a reason why the developers chose
> this method, but it is plain dog ugly. Is there some technical reasons
> someone could explain or is the OSD subsystem in serious need of redesign ?

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.

Regards

Mark