Originally Posted by HIPAR
I'd hate to be the person tasked with defining visual standards. The problem here is HD (or whatever) is ultimately defined by what you see. Vision is a very complex thing. I've seen endless debates about what you can or cannot see such as that chart relating viewing distance to screen size. That's OK for a first order analysis but when you get into more detail, analysts start talking about exotic concepts like 'modulation transfer function'.
Sorry, but this thread has diverted from what Comcast has done to HD signals into two other related, interesting, but different subjects:
1) Verizon advertising and the use of the term "uncompressed".
2) "What is HD?" And is Comcast violating some law or something.
The FCC has been struggling some with this issue too. Basically it is centered on concerns that the cable companies would "materially degrade" the quality of broadcast stations on cable. There have always been somewhat vague "rules" against this, and they have struggled with this definition as part of the rulings requiring cable to assure that after the digital transition cable customers will still be able to see their local stations on their analog only sets.
The complete Report & Order is here
They had asked for comments on how to quantify material degradation, and were really not able to do so. Once concept that received a lot of attention was the requirement for cable to pass through all program content bits. (Essentially the 19Mbps "requirement" that some here have suggested).
6. In the Second Further Notice, we sought comment on proposals for ensuring that broadcast
signals would not be materially degraded after the digital transition. We proposed that the measurement
by which we determine whether an operator is degrading the broadcast signal change from a subjective to
an objective standard or, in the alternative, to maintain the comparative standard established in the First
Report and Order. We asked whether we should require cable operators to pass through all primary
video and program-related bits (content bits).
They ultimately rejected this proposal:
9. We considered the all content bits proposal, the main benefit of which was a clear means
of measurement and consequently ease of enforcement. Ultimately, we conclude, however, that the all
content bits approach is likely to stifle innovation and the very efficiency that digital technology offers,
and may be more exacting a standard than necessary to ensure that a given signal will be carried without
What they DID end up with was retaining a more nebulous (and ominous) standard that was already in effect:
7. We retain the requirement that HD signals be carried in HD, as well as the comparative
approach to determining whether material degradation has occurred. In 2001, the First Report and Order
established two requirements to avoid material degradation. First, "a cable operator may not provide a
digital broadcast signal in a lesser format or lower resolution than that afforded to any" other signal on
the system. Second, a cable operator must carry broadcast stations such that, when compared to the
broadcast signal, "the difference is not really perceptible to the viewer."Thus, "a broadcast signal
delivered in HDTV must be carried in HDTV."
The ominous part of this, to me, is the phrase "the quality of signal processing and carriage provided by a cable system for the carriage of local commercial television stations will be no less than that provided by the system for carriage of any other type of signal. I'm concerned that if they degrade (such as Comcast has done) all the other
cable HD channels then they can also degrade the local stations as well! Till now, I believe that ALL cable systems have NOT put 3 (or more) local commercial HD stations on a QAM - but it would appear that if they degrade the rest of their cable HD channels then they can do it on the locals as well. I sincerely hope that this is not the case - but I've got to wonder.