July 2006

"Leaky Pens" and Lower Definition

What happens when a national network takes the pains to cover a remote in HD? If your're getting your HD from your local cable provider, it's kind of a joke.

Now before I go placing blame on my cable provider, when it comes to digital signals, the home viewer (even one who has worked in the business) has a hard time figuring out who's to blame. In the days of plain old analog, if the reception sucked, it was probably the fault of the cable company - because usually if the problem was at the station, they would put up a "Technical Dificulties" super. In the wonderful world of MPEG-2, Stat-Mux, 8-VSB and 64-QAM it's almost impossible for the viewer at home to divine where the bits have fallen out of the bucket.

The show that sparked this diatribe was my viewing of "Capitol Fourth", the concert and fireworks display carried locally (in HD) where I live by WNET and Cablevision. The first thing I noticed was that whenever there was a dissolve to or from a taped piece of 'b-roll', the dissolve looked awful. "Not enough bits being allocated", I thought. But I knew that there were "leaky pens"* in use when, during Jason Alexander's solo number, the audio went to the digital equivalent of south. (It was fine on the SD 'cast.) There were some obviously some efforts by some engineer somewhere to locate the correct "leaky pen" as the picture took some breif hits, then a longer disturbance and lo and behold the picture and sound returned together !

Now before I let cable companies off hook altogether, let me just mention my one and only viewing of the Time-Warner Manhattan HD service. First I watched (or more correctly, attempted to watch) Discovery HD. Now this is an HD network that Cablevision does not offer on its HD tier. It is also a network that is anal about the quality of submitted materials. (Editing in the compressed domain is not permitted except in narrow and hard fought-for exceptions.) The bit rate on this channel was so low, that except for the fact the picture was 16x9, I thought I was watching the old analog feed out of Group W in Stamford. Then I changed their to WABC-DT feed to watch some 'Good Morning America', which I get at home - so I have some basis of comparison. The bit rate there was set too low as well. If I had TW's HD service I'd ask for my money back!

And then there was NBC's SD broadcast of Macy*s fireworks... very disapointing after last year's HD 'cast. Perhaps a topic for it's own Blog entry ?

* "Leaky pens" is a quote from former ABC President of Broadcast Engineering and Operations Julie Barnathan, referring to digital time base correctors that did not maintain the proper vertical blanking.