[mythtv-users] RE: nvidia new drivers hdtv/interlacing, any benefit for us non HDTV people?

[Bruce Markey]

Thomas Börkel wrote:
> HI!

Hello.

> Bruce Markey wrote:
> 
>>> I'd like someone to confirm that interlacing modes
>>> truly have no effect on tv-out.
>>
>>
> 
> [...]
> 
>> The issues of aligning the image or de-interlacing the image
>> if it cannot be aligned are exactly the same for tv-out with
>> the 4363 driver and tv-out for the 6105 driver.
> 
> 
> OK, then please can someone explain to me, why a 720x576 video captured 
> interlaced looks perfect when played back with the PVR-350 TV-out and 
> looks blurry when played back to an NVideo TV-out at 800x600?

PVR-350 != nVidia, of course =). The 350 is built as a dedicated
TV device and so they put 576 pixels of height on 576 scan lines.
No other heights for TV output and no underscanning to try to fit
inside the screen (this is why the myth GUI size is needed to make
things fit). They also update their frame buffer during the vertical
blank interval so the vsync or jitter reduction do not apply. This
makes it a truly synchronous PAL playback image and no de-interlace
algorithm is needed because there are no mis-aligned interlace
artifacts to cover up.

> What does the PVR-350 different or what can be done to improve the 
> NVidia output?

Heh, wouldn't it be nice if that could be boiled down to a
single number answer like "0.979" (sort of like "42" in the
Hitchhiker's Guide ;-).

--  bjm