[mythtv-users] S-video & widescreen - both in and out

[garydawes at blueyonder.co.uk]

> David wrote:
>> I don't think you can.
>> from :
>> http://www.creativevideo.co.uk/pages/cvp_info_widescreen_explained.htm
>> "It’s a common misconception that there are more pixels in a recorded
>> 16:9 SD image than a 4:3 one because in reality all PAL D:1 images are
>> actually 720x576 pixels, it’s just that a true 16:9 image is
>> anamorphically squeezed into 720x576 pixels…"
>>
>> So a TV signal (again, AFAIK) only contains 720x576 pixels.
>> A widescreen TV signal has the same number of pixels but each pixel is a
>> different shape (in fact, for anamorphic, they're not even the same
>> shape as each other - I *think* anamorphic is not relevant here)
>>
>> So (again AFAIK) there's no point in messing about with resolutions -
>> the card will essentially scale to 720x576 anyway.
>>
>> This all changes for 16:9 projector (and probably 16:9 plasma/lcd
>> screens and HDTV) where there are a different number of pixels.
>>
>> My projector actually has 856x480 (square) pixels (the US is a big
>> market so I get stuck with NTSC height <sigh>) so in my case the
>> applications can just scale the video and it all looks fine!
>> (This is just by way of giving you a decent argument to give to the wife
>> to buy a projector <grin>)
>>
> Same here. Actually I find I get a much higher video quality by
> outputting 720x576 and letting the Plasma do the scaling instead. It
> seems the scaling algorithms in my video chipset (VIA) aren't a match
> for JVC's!
>
> --
> Ivor
> http://www.ivor.it
>

I'm in the UK, and think I've managed it. I initally had it where Mth was
set to 4:3 and everything looked ok, but changing to 16:9 via the W
dropped everything into a 2 inch high letterbox

I'm recording from sky via svideo into an analogue card which captures at
576x288.

I setup the displaysize parameter up in my XFConfig, had to fiddle with
the numbers to get the fonts and everything to scale correctly, halfed
them if my memory serves me right.

I then forced the aspect ratio in playback settings to be 16:9, and
everything now appears to be OK on playback. The W key now cycles through
ok.

The recordings still report 4:3 in Nuvexport, but I've cobbled the ffmpeg
dvd export routine to include the -aspect option to force to the output to
16:9 otherwise the exported recordings are squashed into 4:3.


Hope this is of some help.

gary