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Aura UHD android TV recorder November launch

Yes. A quick instant survey:

BBC1 HD - 1080i
BBC2 HD - 1080p
ITV HD - 1080i
C4 HD - 1080p
C5 HD - 1080p
BBC4 HD - 1080i
QUEST HD - 1080p

...and by contrast:

BBC1 - 576i
BBC2 - 576i
ITV - 576i
C4 - 576i
C5 - 576i
BBC4 - 576i
QUEST - 576i
 
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Thanks. That makes sense. If with a given Aura / TV combo you find the Aura works best (or at least is your preference) for upscaling you set its output to 2160p and by contrast if you find your TV upscales better then set the output to 1080p, although from post #482 there may still be some conversion going on to get to that.
A bit of searching suggests that the Beeb regard full HD on iPlayer as 720p, although I am aware that they are playing with streaming UHD as per https://www.freeview.co.uk/blogs/4k-content-watch-free-now and the other DTTV players don't even appear to support HD for set top boxes.
Hmm, set top boxes... that's a rather outdated phrase. Try putting a box on top of any set these days and it'll fall off.
 
Interesting. When I was doing the survey, I noticed there was p/i switching going on - but dismissed it as me misremembering or incorrectly recording (I saw ITV HD on 1080p, wrote it down, then when I went back it was on 1080i so posted that instead).
 
I can't find any confirmation of that online.
1080P broadcasts started in 2011. https://www.theregister.com/2011/05/23/bbc_hd_1080p/

In January 2012 xyz321 reported that ITV was broadcasting some of their programmes as 1080p.
In recent weeks some programmes on ITV1 have been 1080p (e.g. Downton Abbey).

The situation continues with the BBC sometimes varying what they use within a programme and some channels broadcasting 1080i for some programmes and 1080p for others.
Although for the BBCB mux HD channels, earlier morning at about 9:45 I was receiving 1080p on at least BBC2 HD and ITV HD. Although the current programmes on ITV HD and C4 HD are currently 1080i, most of ITV HD adverts were just now 1080p, and for C4 HD all the adverts during the current commercial break have been 1080p with the initial trailer being 1080p and the ending trailer being 1080i.

Over the years I have had the impression that in the evenings a higher proportion of the actual progarmmes are broadcast using 1080p than during the day.
 
It's 1080p25 vs 1080i50.
The former gets used for stuff which looks to the encoder like it's film (or been film-effected), the latter for proper video.
This can change dynamically within a programme, dependent on the content.

(Why is FF putting a red underline thingy under 'programme'? Grrr...)
 
Is nothing broadcast as 1080p50?
No - that's double the data rate and therefore double the bandwidth and double the transmission cost, and unnecessary.

Analogue TV was always interlaced, with the odd lines in the frame being transmitted in one frame interval and the even lines in the next frame interval. The effect is to double the vertical resolution available without doubling the required bandwidth. The frame rate is defined by the mains frequency - 50Hz in the UK and 60Hz in the 'States - because if TVs were out of sync with the mains it created nasty beat effects in the display (with the technology of the day). Thus half the lines being transmitted 50 times a second is a 25Hz overall frame rate, the analogue equivalent of i50 (i = interlaced; p = progressive, ie a whole frame in one go).

The human visual system (eye and brain combined) does not require refresh faster than 25 frames per second to perceive stop-motion as continuous movement. It's only gaming geeks who want the fastest possible response time for elite competitive gaming and claim to need 50Hz+ refresh rates (and are prepared to spend a fortune on 120Hz monitors plus the necessary hardware to drive them).
 
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No - that's double the data rate and therefore double the bandwidth and double the transmission cost, and unnecessary.



The human visual system (eye and brain combined) does not require refresh faster than 25 frames per second to perceive stop-motion as continuous movement. It's only gaming geeks who want the fastest possible response time for elite competitive gaming and claim to need 50Hz+ refresh rates (and are prepared to spend a fortune on 120Hz monitors plus the necessary hardware to drive them).
So 50Hz is never needed for TV? Even setting it as your output on a box or your TV is unnecessary?
 
So 50Hz is never needed for TV?
Well, for the vast majority: no. There might be just a few people who can perceive some jerkiness in fast action at p25, but that pretty much disappears by using interlacing - you get a low-res image every 1/50s, which integrates over two frames to produce a full-res image.

Cinema (using film, not digital) is effectively progressive scan (the whole image changes each time), and is 24fps. Do you have a problem with jerky action at the movies? Do you think they would have standardised on 24fps if that wasn't fast enough??

Even setting it as your output on a box or your TV is unnecessary?
I have my PVR output set to 1080i, because there's no visible difference and it cuts HDMI radiation. The HDR-FOX output setting "1080i" means 1080i25, and the setting "1080p" means 1080p50 - twice the bandwidth, pushing the noise spectrum into the UHF band, and the extra information has to be invented (interpolated) anyway.

On the other hand, the broadcast "1080p" is 1080p25 - a whole frame transmitted every 1/25 sec, as opposed to i25 which is two half-frames transmitted every 1/50 sec. Therefore you might expect fast action to be worse at p25 than at i25.
 
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Probably got US English selected
Right click while replying and select Languages
Is it really that simple? I thought it was simple but not that simple. For Firefox doesn't dictionary "British English Dictionary (Marco Pinto)" also need to be installed?
 
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