[opendtv] Re: Poor quality PBS ATSC feeds

Kon,
You are not losing your mind. About two out of every three programs on the PBS HD service is actually upconverted widescreen SD.
PBS delivers the HD service to member stations via an ATSC ready transport stream. About 17 Mbps at 1080i. The macroblocking is awful. I've lobbied PBS to convert their HD to 720p because of the limitations in the bandwidth, but their reply is that 1080 is better than 720. Bigger number, I guess.
Then, the last question is was the local station you captured the video from performing a multicast? More and more PBS programming directors seem to believe they can broadcast an HD and two or three SDs simultaneously, with predictable results.
We are no less guilty than most other stations, in that we broadcast one HD (in 720p) and one SD. Stat muxing helps, and we are in the process of upgrading our Tandberg encoders to add multipass encoding. But with the expected improvement in encoding efficiency of multipath, our program director plans to add two more SD services. 

John
----- Original Message ----- From: "Kon Wilms" <kon@xxxxxxxxxxxx> 
To: <opendtv@xxxxxxxxxxxxx>
Sent: Monday, April 23, 2007 8:32 PM
Subject: [opendtv] Poor quality PBS ATSC feeds



Folks,

Just an inquiry to check if I am not losing my mind (which may be true
regardless) -

Prior to NAB I captured a number of programs from local PBS stations
in LA (KOCE and others). Specifically wildlife, nova and other nature
feeds to use for 'demo' purposes. Well, until I actually got them onto
my PC and decided to play them fullscreen for a test. Half the
programming appeared to be upconverted 480p. The other half that was
720p or better had so much macroblocking from high compression that I
had to discard them completely. Unwatchable is an understatement.
Embarassing for whoever configured the encoder is probably more
spot-on.

Am I the only one having this experience?

Cheers
Kon





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