[mythtv] XV, alternative output & independant OSD resolution (was: Overscan GUI problem)

[Erik Arendse]

At 30-1-03 13:04, Bruce Markey wrote:
>Erik Arendse wrote:
>>BTW: If you never saw a teletext system resolution, just think Commodore 
>>64 on a TV, it's exactly the same.
>Is there a big blob in the middle of the asterisk? ;-)
Sort of :-)
>I've certainly seen a Commodore to understand that amount
>of text but I've never seen teletext. 25 lines does seem
>aggressive but possible with 576 lines.
Found you a load of examples: 
http://teletext.mb21.co.uk/gallery/ceefax/main2.shtml
This is all level 1.5, meaning all the fancy stuff left out. There are 
several more levels of features defined in the standard, level 1.5 is just 
8-color fixed character table. Never seen any other levels for real though...

>Close caption seems to be more like a simple markup language
>rather than a defined layout. It appears to me that different
>TV's have different fonts that are generated in the TV set
>and overlaid. There seems to be some simple instruction to
>put text at the top or bottom, italic, and even codes for
>colors. Two TVs side by side might wrap lines in different
>places like two different web browsers wrapping paragraphs.
Yuck...
I'll just include the cc-decoder somebody posted on this list with my 
subtitle/caption patch then, and I'll leave it to a native american ;-) to 
connect it's output to my OSD module.

>>I heard US closed captioning displays color on black as well?
>It usually cuts a black rectangle around each character so
>the screen has these black stripes that grow left to right
>across the screen covering up everything in its path. Very
>destructive.
Probably even more destructive in countries where people are used to native 
language shows or dubbing. My country is too small to afford dubbing in the 
past, and nowadays everybody is used to subtitles. Very good for learning 
other languages :-)
My module will support transparent background by default, possible with a 
toggle to make it black if it disappears on a while background. Makes 
MythTV usable for the deaf as well, besides adding seachfunctions, 
text-while-muted and foreign language subtitle selections.

THNX for the 'xruler' and other pointers.

>PS Do you have any suggestions for PAL recording sizes?
>I assume 576 and 288 for heights. Are there any suggested
>widths common for PAL DVDs, DVRs, VCDs, etc.?
Simply put: Yes, a lot of suggestions, and No, not really common.

On http://www.vcdhelp.com/dvd.htm at the lower half of the page is a 
beautiful comprehensive table.

And to get a headache http://www.vcdhelp.com/forum/userguides/94382.php 
tells you what we want to know: how does digital resolution end up on TV... :-(

To complicate things even more the BTTV drivers have their own opinion on 
usable resolutions as well.

Erik