Monday, February 04, 2008

Quality Counts

Professional broadcasters have always taken the quality of their output very seriously. And advertisers were even more particular once upon a time.

So, for example, it's truly galling to see the BBC spend hundreds of thousands of pounds covering the six nations rugby games and then promoting their availability as streams on their iPlayer (incidentally, apparently the iPlayer was a failure as a download medium, but has become a great success since they introduced streaming, insiders tell me).

But the quality of this content on the iPlayer - using On2 codecs as a sop to Macheads - sucks. Twelve years ago I managed to get primitive computers (remember 256 colour graphics drivers ?) to play video (I seem to remember we got an Elton John video playing from a floppy disk - what a dinosaur, eh..?) , and the quality offered today by the BBC for their main streaming service is considerably worse than that. It's certainly an improvement on their simulcast coverage of sports, done veristream at around 30Kbps, which is just a sensless blur. And all the time you have to remember that you pay a substantial tax to these people (or two taxes in my case...)

Sport is very difficult to encode due to the movement and, for team sports, a green background is very decoder unfriendly. Still...

With Flash Player it's not possible to ascertain the streaming data rate, but the output from the iPlayer for the rugby is akin to bad 200Kbps VC1 encoding.

Flash video remains inferior to VC1 in quality, even with the adoption of H.264, but an investment in decent equipment - and more importantly - in technicians who care about the quality of the video output (just like you employ hundreds of engineers to worry about the quality of your TV pictures, BBC) would seem like a wise move.

In two decades of dealing with the delivery of video over PC and IP networks the one thing I've learnt is that video encoding is an art not a science. Setting up a bog standard box and someone on work experience is not how TV becomes IPTV. I've employed people whose sole roles were to work on the quality of the transcoded video quality, who were obsessive and talented individuals, so I can't see why the BBC can't.

Just like the current 1020 line HD TVs seem sharp, whilst the original 30 line and even 240 line TV images developed by Logie Baird seem primitive. So, YouTube will not remain acceptable for long. Especially when there are far superior formats already on the market. The swing from availability to quality will inevitably come, just like an old fashioned 16" box TV now seems a joke next to your average 42" LCD screen.

Ubiquity may well be the enemy of quality, but complacency cannot be forgiven..

2 comments:

Anonymous said...

"Flash video remains inferior to VC1 in quality, even with the adoption of H.264"

How so? I read that a lot but there's never a reason why? All are capable of HD video. VP6-E and VP6-S are exceptional at low bit rates. I've even seen some HD Flash with H.264 at only 500 kbits/sec.

Iolo said...

It's down to the efficiency of the codec. True HD at 30fps full HD is around 158Mbps/sec - so, technically, it's not HD at 500Kbps, it's just well encoded video! However, HD on the telly is also heavily compressed - to my trained eye at around 3Mbps for highly contended sports events and 8 - 10 Mbps for general broadcasts.

Encoding, as I stated, is an art, not a science, and getting the settings right for a specific clip can make all the difference to the quality. However, I still believe, that all factors considered, VC-1 is a superior codec to H.264.

As for the On2 codecs your refer to - empirically I think they're very poor indeed. If you can point me to well encoded Flash Video (apart from the handful of H.264 demos), I'd love to see it (not that it seems to matter to much to your average YouTube viewer!).