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Sky Movies - Picture Quality Deterioration
It would appear that Sky have been shuffling channels on transponders again and, at the end of last month, moved National Geo, National Geo +1 and British Eurosport onto TP7 (11.837H) alongside Sky Movies 1,2 and 3. This has resulted ina significant drop in picture quality with softness and pixellation now much more common, particularly in dimly lit scenes. This was very noticeable with the premiere of 2Fast 2Furious last night.
Have others noticed the drop in quality?
I trust this will only be a temporary "glitch" or I'll have to seriously think about buying DVDs again. I have never worried too much about DVD extras and with the quality of picture available until recently on SM1 and 2 (even on a 50" plasma), I was quite happy to wait a year until a film was shown on Sky Movies.
Perhaps this is a move intended to make Hi-Def look even better when it arrives in 2006!
TC
Have others noticed the drop in quality?
I trust this will only be a temporary "glitch" or I'll have to seriously think about buying DVDs again. I have never worried too much about DVD extras and with the quality of picture available until recently on SM1 and 2 (even on a 50" plasma), I was quite happy to wait a year until a film was shown on Sky Movies.
Perhaps this is a move intended to make Hi-Def look even better when it arrives in 2006!
TC
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For a long time though i have always thought SkyMovies was giving the best picture quality on the TV over my DVD player, but then i changed the DVD to a new 12bit/108mhz player with the progressive scanning and YPbPr stuff, and now the quality looks absolutely superb, if this quality could be achieved on all sky channels with the standard 4-5mbps bitrate of the DVD's i tested then i'd probably think twice about bothering with HDTV... but as it stands HDTV all the way
SM1 and SM2 are more badly affected than SM3.
Picture quality on other Sky Movies channels is still pretty much OK, as it is on the 4 other channels on this transponder.
Typical 2 hour movie on SM1 now only occupies 2% of 120MB hard disk on Sky+ or around 6% on 40MB. This roughly equates to a bit rate of:
(40,000,000,000 x .06 x 8 bits per byte) / (120 minutes x 60 secs) = 2.667 Mbits / sec
This is a damn sight les than one seventh of the available capacity per transponder which, as far as I recall and after application of the FEC factor is about 36 Mbits / sec and suggests that Sky's bit-rate allocation is NOT what its should be.
If anyone technical from Sky is reading this, please would you fix it!
TC
The Simpsons picture Quilty last Sunday was awful it looked like a badly encoded MPEG.
checked signal quality and strength which was 100% strength and 90% quality.
so i guess its the stream thats crappy.
jon
MPEG4/H.264 achieves this by compressing the pictures using a smarter algorythm. This also means the decoder must use a faster videoprocessor. Try playing your HDTV-XviD's on a 1GHz PC and you'll know what i mean.
Sky uses MPEG2 which uses a less efficient compression algorythm. HDTV-quality streams in MPEG2 would take up a lot more space than your XviD-files.¹
Remember that MPEG2 is almost (or over?) 10 years old now. You can't expect the same results from a 10-year old algorythm that you do from a fairly new one
¹= this isn't possible by the way, as MPEG2 doesn't support HDTV-resolutions. Hypothetically, HDTV-quality MPEG2-files would be a lot bigger though.
It certainly was (and I'm always saying MB when I mean GB!) but the calculation had the right number of zeroes (and yes I do know that 40GB is actually 42,949,672,960 bytes).
TC
Those files were capped from a HD source and then down converted to something like 624*352 which is a lower resolution than PAL. Given the higher quality source material you can see why these look so much better than caps from a couple of years ago that were mainly from NTSC sources. I can't comment on how the xvid caps look on a large TV since I have to re-encode them to something my current DVD player accepts either SVCD or DVD spec.
While they do look stunning on the PC I would still rather watch CSI Miami (for example) on Dsat Five then a capped version of the show:)
When SKY launch their HD service there should also be benefits for viewers/subscribers who have a HD STB but are down converting to PAL. The resulting picture should be better than the standard PAL standard definition broadcasts.
Assuming SKY include the ability to downconvert a HD signal to standard PAL then yes you could get a superior picture from the HD service on your standard PAL telly.
Internal scaling is pretty much the norm for the current HD boxes around the world and I would be very surprised if SKY launched a HD STB then didn't have this feature.
I expect the cost to be around £400, after all the people who would be buying would already have spent thousands on suitable displays and then be prepared to spend X amount for an additional HD package. However since the current mpegII HD STB's are around that price now come 2006 I would hope that advances in manufacturing and the size of inital production runs would bring the price down to around £300.
Just like SKY+ the early adoptors will still have to pay the premium prices to get the kit:)
Again you have to assume that SKY will incorporate HD recording in it's High Def STB, I can't see any real point in not doing so and then the capacity would depend upon the codec used. If they stick to mpegII you would need a 250gig at least, if they use mpeg4 or wm9 then you can have a smaller hard drive and be able to record the same amount.
The cost of the hard drives and there long term supply will also be a factor in the decision on what capacity/drive to use.
All that happened, on being put through to the technical area, was that I ended up talking to someone who just wanted to start an argument with me... "The only thing that can possibly be is a problem with your signal reception etc. etc." For the record, I know damn well it isn't but what does that count for with these idiots?
Does anybody have an e-mail address of someone in Sky that might listen to genuine concerns from one of their subscribers about this deterioration in picture quality?
TC
This BETTER be a technical fault or I will seriously consider cancelling my digital subscription with them. And it is NOT my digibox fault either, because ntl here in Ireland receive their channels from astra too, and the exact some problem is occuring with the ntl analogue feeds of the channels as with the digital feeds from sky.
Thank you for your support and confirming I'm not going mad.
Now do we think Sky are actually aware of the issue or is it a deliberate act? Could someone with good technical contacts in Sky, like AlanJ do some digging for us?
TC
If anyone is interested, the quality on Telewest has been poor recently - especially on SKY One ( E4 looks blocky as well ). As a couple of the other posts mentioned, Voyager and The Simpsons were/are particularly poor - so it isn't just SKY.
Thanks.
You've taken a variable bit rate and tried to average it which is impossible to do, the channel is multiplexed to provide the channel with the bandwidth it needs, afterall the picture does not pixellate during high bitrate scenes does it , with a plasma its no surprise there might be some problems but most of them are geared up (or should be so) for HDTV not SDTV , most people watch the services on 32'' or less tv's and the quality is fine. No major outburts of protests from lots of viewers seem to be happening.
E4 has always been crap quality. Somes up Channel 4 channels in content to
I presume that Sky must be using more compression or something before the channels are uplinked, perhaps space saving for HDTV tests or something
To be honest I havent noticed any difference on Sky Movies on ntl, I havent watched Sky One in about a year.
Further it depends on the memory your sky decoder has. Older boxes had less memory and a slower processor. Old pace boxes etc. Channel listings slowwwww.... If you look at your version number no * next to it means older memory the star is enhanced memory.
Any furthers questions message me I can help with almost any querie here dont be afraid to ask.