Thursday, February 01, 2007

Which and the Blu-ray conundrum, HD-Ready, plus an appeal for information.

I received the latest copy of Which magazine yesterday and whilst flicking through it found an interesting article regarding some tests they ran on a couple of new Blu-ray players. They complained that the picture was jerky, which they attributed to the fact that the disc was encoded at 24fps, not 25fps.

Okay let's stop there; the film industry standard is 24fps. It's the UK broadcast standard that's 25fps (50Hz doubled output) in the USA it's 30fps (60Hz) So given the fact that what they're watching wasn't designed to be broadcast why should it be encoded at 25fps?

It gets better - Blu-ray is 'format-free' it's not PAL (UK) or NTSC(USA) or even SECAM(France), so in theory we should be able to buy Blu-ray movies from the USA and watch them without worrying about whether our TV can handle the input signal. Well we can't as the movie industry has carved up the world into 'zones' in the same way as they did for DVDs, but as I explained this time there was no real formatting reason.

However what about the Which complaint? Well if UK films are encoded at 25fps and US films at 30fps, we're back to the bad-old days of 'will my player/TV handle it?' What should be asked is

"Why doesn't my television input a HDMI signal at 24fps?"
The wonderful HD-ready 'standard' we have in the UK is useless (in more ways then one as I'll explain later) as it only stipulates that the television can input at 50 and 60 Hz not 24, 48 or 72. So every player would have to upscale a 24fps film to the television. Which magazine shouldn't be blaming the player, they should be asking why HD televisions can't handle the film industry standard natively.

Which brings me neatly to the HD-Ready specification. HD-Ready, buy a television with this label and you've got a high definition capable television; haven't you? The official specification of HD-Ready has become quite tricky to track down, neither the HD Ready site nor the EICTA seem to provide any links to the official version despite the fact the EICTA is named on several manufacturers' sites as being the creators of it.

Thank Google then for a link to a document and the HTML translated version of Requirements for the label “HD ready” which makes interesting, if scant, reading for those with a technical bent. Note that these are the minimum requirements, televisions can exceed these if they want to.

So dealing with resolution -
The minimum native resolution of the display (e.g. LCD, PDP) or display engine (e.g. DLP) is 720 physical lines in wide aspect ratio.
and the definition of "wide aspect ratio" is... not given. What does that mean? Well in theory I could build a television with 720 horizontal lines and 720 vertical lines, so long as I made the width of the pixels greater then the height to get that "wide aspect ratio". It'd look terrible, but would it get an "HD-Ready" sticker; after all there's nothing stopping me or is there...
b. DVI or HDMI HD capable inputs accept the following HD video formats:
i.1280x720 @ 50 and 60Hz progressive (“720p”)
ii.1920x1080 @ 50 and 60Hz interlaced (“1080i”)
Ah ha! See it has to have at least 1280 pixels for its width. Oh but wait by that interpretation wouldn't it mean that it had to have a minimum of 1920 vertical lines and oh 1080 horizontal lines too? That contradicts the first requirement. Look closer, it has to input these resolutions; what it outputs to the screen is entirely up to the manufacturer.

So a 720x720 screen that inputs, and is forced to downscale, 1280x720 and 1920x1080 could in theory be awarded an "HD-Ready" label and sit on a shelf somewhere for some unsuspecting customer to pick up.

Okay I really doubt that any manufacturer would create such a monstrosity, but it just goes to show how flexible this 'standard' is.


Okay now an appeal for information, does anyone know what the building work on the side of the Stourport-Kidderminster dual-carriageway is? I've had a look at the planning applications, but nothing relevant is showing up for "Minster Road", "Stourport Road" or even "Kingsway". The only thing that shows up for "Walter Nash Road" is a B2/B8 development, but I'm sure that's too far down the road as it's just comes in just below Zortech Avenue. I'm driven past it a few times and I'm sure it's closer to the slip road down to the tip then it is to Birchen Coppice. I may be wrong, so can anyone help?

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