One of the hallmarks of Microsoft is that we dream big - Steve 'Understatement' Ballmer
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BBC HD isn't
AUNTY IS GETTING SLAMMED by the great unwashed over the quality of its High Definition telly images.
Viewers have been complaining of fuzzy and grainy images and yet the head of the channel, Danielle Nagler, says that despite a series of tests, no technical fault can be found.
She pointed out that not all HD programmes have the "bright, crisp look which for some is synonymous with HD." Some camera and production techniques simply are not up to scratch yet, she said.
The BBC replaced the encoders that process HD pictures in August 2009. Its new encoders work at a bitrate of 9.7Mbps while their predecessors worked at 16Mbps, which is the industry standard.
However the Beeb insists that even if the old machines had a higher bitrate the new encoders can produce pictures at the same or even better quality than the old encoders at the higher bitrate.
The BBC claims it has only received one official complaint so far. µ
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Yep, 9.7MBits doesn't sound great for HD
- not really enough for a picture significantly better than SD!
"the new encoders can produce pictures at the same or even better quality than the old encoders at the higher bitrate."
Probably true, but very doubtfull that the bitrate can be 40% lower with the new encoder for the same quality.
The biggest advantage of newer encoders is that the artifacts are not as conspicuous, even with a reduced bit rate. However, to get produce actual fine detail, you need a higher bit rate. Otherwise, general blurriness reduces the effective resolution.
9.7Mbit/s IS enough to encode HD video and sound such that it basically indistinguishable from uncompressed. The MPEG4 AVC profile is a very flexible and forgiving standard with lots of ways of skinning the same cat. Its no surprise that a different encoder could cut 42% of required bandwidth out of the picture.
The real issue is real time compression. You get the best results by being able to optimise over a good chunk of video sequence with hefty processing capability to optimise the blocks, etc. over the time/space domain. That's difficult if you are real time compressing sport - which is where the problems with the new encoder seem to lie. Some mods and fixes and there is no reason why these won't work OK in the end for the Beeb.
I get the feeling people are seeing the headline figures and thinking it MUST mean lower quality. If you do the right job with the encoder there is no requirement for it to be.
Maybe the Beeb could organise a blind taste trial; with uncompressed and compressed content side-by-side for users to compare?
You will not get PQ "indistinguishable" from the original at 9,7 Mbit/s (AVC). Especially if you have lots of fine detail on screen or noise, combined with movement. Even at 15 Mbit/s it is easy to see the difference in noisy images; at some points in the image there is easily visible noise, at others there is artificial smoothness. This is very evident in Blu-Ray movies. And it isn't helped by the fact that HD cameras are generally more noisy than SD cameras. Unless, of course, you have optimal studio lighting.
But to be able to tell you are losing fine detail, you must compare the image directly to the original and look at fine details (individual hair strands are often not visible). Mostly people just don't know what they are missing. And you can't watch the image on a too small TV, or too far away from it. Anyway, to get the "movie experience", the TV diagonal should be 72 inches from a distance of three meters (10 feet), giving 30 degrees horizontal.
Links?
Why is this news?
Why is this news Today?
BBCAmerica is supposedly HD on cable, only. As I use DirecTV STB, I don't get HD there yet. So I still see it as a digital channel.
The letter boxing is different than most and my STB allows me to crop the image. On "HD" channels at 1080i, no reformatting is possible with the STB. I have to endure the artsy-fartsy letterboxing, but on digital channels it still works. Why can't everyone use 16:9 ratios?
I have two "local" channels (the CW is one) which are supposedly HD, but their programming is now effectively all displayed in a pillow box having a huge border on all four sides wasting the screen.
What's it all about? I believe that there is simply not enough smart people to flip the right switches.
9.7MBits, I believe standard Freeview is around 6. I know SD is mpeg2 and HD is mpeg4 but 9.7MBits for HD is pathetic
Being a huge Top Gear fan, I could barely contain myself when it came out in HD this fall. The quality compared to the previous broadcasts was just amazing. However, I can clearly tell some of their cameras were not upgraded, mostly the in-car narration shots. But the quality of the signal is otherwise top notch. I watch it with a 120" front projection system @ 720p. So I think the BBC statements are in line with what I have seen so far.
I'd be happier with my FreeviewSD being broadcast at 9.7Mb. Then it would look like it should, instead of 'blockavision' as soon as any action happens.
BIt Rate
Yep, 9.7MBits doesn't sound great for HD
- not really enough for a picture significantly better than SD!
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ok regarding the above - obviously too stupid to know whats going on outside the rock.
UNCOMPRESSED 1080p only spikes at 40mbit, and even those providers that say they are giving real hd are typically not bursting at higher than 18mbits.
9mbits == 5793MB over only 90 minutes, 7724MB over 2 hours, plenty of room for a fully compressed h264 1080p.
please sir, keep loading those 3GB sddvd rips on your ipod ~_~;
Not sure where you learnt math but your numbers just don't work (though the order of magnitude is fine).
I do have 4.3GB 1.5hr 1080i torrents, they look really good. Use that number to judge other codecs.
More important since it's my day job: UNCOMPRESSED (your caps) 1080p is 2.97Gb/s (or 2.97/1.001 to be comprehensive, stupid American 59.94Hz rate). That's the SMPTE standard. if you put caps, please avoid using the wrong word. That's a bit more than your 40Mb, that's why you need good compression.
What you guys dont realise, is that we have a HUGE problem with bandwidth hogging. Over 25% of bandwidth used is youtube, and over 10% (in the UK) is the bbc iplayer. The reason this is a problem, is that video streaming is alot more intesive then web browsing(web- (gives) a network usage spike, streaming- continuos rate upto 100%)
If they can reduce server load, and the load on the inter-city connections, GREAT..
anyway.. 9.7MB/s encoding can be better quality then 16mb/s... just depends how they do it..p.s
BBC iplayer at 720p:
Video 3MB/s (this is gd)
Audio 192 KB/s (most ppl have crap audio anyway)
The article is about 'over the air' TV broadcasts, not the Internet.
I suspect the grainy images or what not do not come from the lack of bitrate but actually the set top box / tv playing them.
The resolution that bbchd broadcasts in is quite special. They broadcast at 1440x1080i. They use a 16:9 flag in the stream in order to get the box to display the correct aspect ratio.
So in effect all pictures are heavily horizontally stretched (33% stretching)
Hardly any tv's natively display 1080i so either the stb or the tv will then convert the signal to either 720p or 1080p and depending on the quality of these converters results will vary.
The problem with this debate is that everybody starts talking about bit rate and compression.
The real issue is much more simple. When BBC HD started it was so good it made lots of us buy into the technology.
Then suddenly it looks no better than SD and at times worse.
Unfortunately it appears that for whatever reason the Head of BBC HD is unable to accept this and spends her time defending the indefensible. Maybe she sees a future in radio.
To me this is exactly the sort of situation that requires a public enquiry. I suspect even the threat would be enough for somebody to wake up and turn HD back onto BBC HD.
Starts off with just barely decent enough bitrates and then as time goes on and (they hope) without us noticing they slowly shave back the bitrates bit by bit so they can cram in another couple of channels of crap.
Then they spend millions on surveys asking why the public isnt buying it.
Always reminds me of a Fry & Laurie sketch from the early 90's where Fry was obviously taking a swipe at the BBC about it's future policies when he supposedly spots the DG of the BBC sitting at a dinner table. The DG asks for some cutlery. Fry dumps a sack of plastic coffee stirrers on the table and shouts words to the effect of "there you go, plenty of choice for you now but pity about the quality!"
Weather forecasts are ugly, and they only show temperatures for 3pm in the day. The older forecasts were better.
London area forcasts don't actually show London. They show other cities around London. What a joke that is. Why show Reading, a small little place when 8-12million of us live in London. Dumb.
Motogp:
Their coverage with the Red Button is attrocious. The SKY and I think the freeview boxes cannot record this red button. They won't show practice or qualifying. And their commentator (Steve Parrish), despite being an ex-racer, misses so many of the rider movements. It's very frustrating to hear average commentary after such good commentary on Eurosport.
Eurosport's Randy Mamola is leagues ahead of the BBC's Steve Parrish. And Mamola still rides the current Motogp bikes as he does the Ducati charity 2-seater rides at most tracks.
BBC have the live race, Eurosport don't so they have let Randy Mamola go. Which is a shame because Mamola was an inside guy, knows all the riders and teams and was able to get great interviews, inside knowledge, explain the tech and hear the gossip.
Plus Mamola would spot small body movements by a rider, or hear the engine or traction contol not sounding quite right, and then inform us, the viewers, of something interesting.
BBC failing on HD is no surprise to me. Probably the same idiot woman in charge of that who was in charge of the handling of MotoGP.
If you're not going to do it right, then give us back our fkcuing money. Don't bullshit us.
BBC, some stuff is good, like their comedy is excellent. But their red button shit is just that, shit. And no timetable for the red button shit either. No info about how many days or what times the programs will be starting on red button. A bag of shit run by bags of shit.