[mythtv] s-video input / widescreen tv ?

[Bruce Markey]

There is a lot of interesting information here. Thanks for
sending this.

Erik Arendse wrote:
...
> We have a special broadcast norm being introduced (since 1995)  which 
> uses PAL to transmit a letterboxed image, but in the black bars 
> below/above the picture extra lines are hidden (in such a way to be 
> below the blacklevel on a normal TV). Using a framebuffer a PAL-Plus TV 
> can use these to reconstruct a 16:9 image with a higher resolution 
> compared to the letterboxed one visible on the 4:3 TV.

If I understand this correctly, the letterboxed lines in
the 4:3 image are common to both then every third or fourth
PAL-Plus line is added. Are there any capture cards capable
of doing this reconstruction? Or, at least assign digital
values to the blacker-than-black information so that the
reconstruction could be done in software?

> Back to the question:
> My TV (Philips, branded Aristona, Philips brand is originally Dutch (but 
> now just another global company) available everywhere - but mostly 
> Europe and Asia - under several names, most models country specific) can 
> lower the vertical deflection so all horizontal lines squeeze in the 
> leterboxed needed to show a 16:9 image with the width of the physical 
> 4:3 tube (Phew, mouthfull...).

Got it. The one thing I want to understand here is if the
only change is that the scan lines are closer together. If
the synch timings change, an X display may not survive the
transition. If it continues normal PAL and merely squashes
down then this would work well for myth. Since the default
is to stretch the image the the X dimensions, and this
squashes the X desktop to 16:9 a 16:9 image should look
normal (with the advantage of denser lines than 4:3 mode).

> This is only useful for DVD (or PC's)  as 
> they are the only 16:9 sources here, packing a 16:9 image anamorphic 
> into a transport developed for 4:3. A theroetical "PAL-Plus to 
> anamorphic PAL" converter could be used as well, but I have never heard 
> such a beast existing.
> By the way: the set does support NTSC the manual says, so if you send 
> some money my way I could put it in a box and ship it your way :-)

I wouldn't feel comfortable sending cash but I would be
happy to offer you ownership of a famous bridge in New York
City in exchange for your TV ;-).

> The benefit of all this is based on the fact that that most of the 
> tranmissions here are 4:3, slowly moving to 16:9.  Most commercial 
> channels here will never transmit 16:9 yet out of fear some viewers will 
> run away when they see a set of black bars.

Interesting, here some shows and commercials deliberately
chop a little off the top and bottom to give the illusion
that it is some special widescreen broadcast ;-).

> If you watch 16:9 on a physical 4:3 you end up with a letterboxed image. 
> The other way around you end up with a vertical "leterboxed" image. As 
> most material is 4:3 I have to watch the smallest hours of black bars 
> this way.

Understood.

> Other issue is that although on paper the 16:9 tubes are bigger, that is 
> only because the diagonal is cited. The final size of a 16:9 picture is 
> comparable within the same price-range for both 16:9 and 4:3, but the 
> size of a 4:3 image will be a lot bigger on the 4:3.

I have a 70" Mitsubishi so the width is 56" by 42" high.
A 56" wide 16:9 screen uses the same guns, mirrors, etc.,
except the screen is chopped down to 31.5" high. Both show
16:9 at 56"x31.5" but the 4:3 image on the widescreen is
only about 42"x31.5" rather than 56"x42". Since the width
is most important in determines the size of the piece of
furniture and the internal components needed, it seems to
me that we're just being cheated ;-).

> Finally a weird tale (to me at least): As we sell so many 16:9 tubes, 
> and as there are so few 16:9 transmissions, everybody puts their TV in 
> some sort of "stretched" mode which deforms the 4:3 picture to 16:9...
> And everybody thinks this is neat, except for a handful of people who 
> use their eyes, including yours truly.

I couldn't agree more. I think the TV sellers benefit from
the "wow" factor. The widescreen shape makes the sets look
like the latest 'state of the art' thing. With a 4:3 screen,
a widescreen image letterboxed looks smaller (less impressive).
On a widescreen set, the 4:3 is smaller than the more
impressive widescreen image. I believe these two reasons
are why the showrooms are filled with widescreen models.

So, they take last year's model, chop down the height, charge
twice as much money, then people take them home and watch
distorted images most of the time. It boggles the mind =).

--  bjm