[mythtvnz] FrontEnds Controlling Audio Mains Power

[Brett]

On Mon, 2010-12-13 at 23:07 +1300, tortise wrote:
> On 13/12/2010 10:45 p.m., Brett wrote:
> > 1080i60Hz is not right should be 1080p60 or i30. 3D NTSC blueray/ might
> > be 1080i60.
> 

To clarify (fix some of my errors from far-to-late night replies) ..

1080i60 is okay if your display can not do p60 or player can not do
de-interlacing. It is a possible symptom that the player/display
combination is not ideal/possible.
Also a symptom of analogue connection.
A limitation of the VGA connection is the very likely lack of 50Hz
modes.

3D blueray probably uses 1080i120 or 1080p48 or 1080i96 for film & NTSC
source.

Assuming PC & PC video card with possible digital link.
Your freeview material & PAL DVDs should be played back as p50


> This is via component - you were telling us we cannot get 1080p via 
> component into more TV's than this one....  Which way do you prefer it?
> 
I prefer to have my cake & eat it..
I never said that...I said there are no TVs (made recently) that will
accept analogue HD signals & I mean full HD 1920. More-over the VGA
inputs are normally worse than they could be; only support std 4:3 video
modes & not native res. 
Effectively they downsample.

> > You should not be using 30 or 60 for NZ recordings as you will have
> > euro-judder&/or possible weird effects from confusing the TV into

> While this seems intuitive the TV info reports receiving 1080i at 50 via 
> its freeview tuner and 1080i at 60 when receiving component from a 9400GT 
> PCI / mythtv
> 
> The NVIDIA gui also reports 60Hz for the TV, cuncurring with what the TV 
> is reporting.
> 
This confirms the setup is not ideal..

> I have no reason to doubt those info reports.  Seems to me NVIDIA 
> effectively converts 50Hz Freeview into 60Hz - and does it well to boot...

This causes euro-judder, observe fast scrolling credits & the TV news
weather ticker/ribbon. These are perfect with 1080p50 & suffer
flicker/judder at 60Hz playback.
The GPU can only do this by using pull-down schemes; adding extra
frames.
One likely scheme is:
For every 5 frames of source ( 1/(50Hz/2) * 5 = 200ms) the output at
60Hz must do n frames(1/(60Hz/2) * n = 200ms) & n = 6.
This scheme results in 5Hz flicker/judder.

I 'borrowed' a 46" V20 some months ago just to expt with the
PQ/videocard so this comes from real experience of the same model
family.

Other PQ HDMI benfits:
I'm no HDMI fanboy but HDMI does allow Y'UV colourspace & >8 bits.
Y'UV colourspace is better suited to video than RGB (not my opinion).
Latest nvidia driver has Y'UV option. Maybe it avoids a RGB conversion
step ?
(Displayport probably capable of the above)