[mythtv-users] DTV: It Has Begun

Yeechang Lee ylee at pobox.com
Tue Sep 9 20:19:11 UTC 2008

Michael T. Dean <mtdean at thirdcontact.com> says:
> IMHO, Europe did the digital TV transition correctly.  They went to 
> digital standard-def (allowing for relatively inexpensive decoders) 
> while planning for the HDTV upgrade.

[A bunch of nonsense deleted]

No matter how often Michael claims this, the facts just don't bear him
out. For the curious non-Americans on the list:

Fact: The US has had almost-universal MPEG2-encoded, ATSC-transmitted
based HDTV over-the-air coverage for most of the *decade*, with the
first digital (and thus, in the US context, HD) broadcasts since the
late 1990s. _The Tonight Show with Jay Leno_ has been broadcast in
HDTV since *1999*, for example. This *despite* the fact that ~90% of
Americans receive television via cable or satellite, and *not*
over-the-air. (Satelite/cable users of course still benefit from the
programming aspects of the HD move, of course; they just don't need an
over-the-air antenna.)

Fact: The six US major English-speaking commercial-broadcast networks
have aired their *entire* prime-time programming and weekend
daytime-sports lineups in HD, minus some reality and talk shows, for
at least three years and in some channels' and programs' cases longer
than that (see above). We are now well into the process of daytime
soap operas, talk shows, game shows, and other syndicated content
moving to HD. The seventh major English-speaking broadcast network, a
non-commercial one, is about 50/50 in HD in primetime in my

Fact: The typical US cable or satellite subscriber has accsss to each
of the above seven networks *plus* anywhere from 5-20 additional HD
channels. I have ~30 HD channels on my cable system here in San
Francisco (plus, as is typical, hundreds of non-HD channels).

Fact: The upcoming February 2009 "digital transition" you've read
about on the list and perhaps in news articles is not turning *on* new
digital broadcasts; as mentioned, that occurred years ago. Rather,
existing analog broadcasts are to be turned *off*.

Fact: MythTV users have been recording and playing back said HD
recordings for as far back as four or five years (There is a message
in the archive, which I can't find at the moment, of someone in early
2004 talking about deleting his 45GB recording of a sports event,
presumably the Super Bowl.) Me, I've been only doing so since building
my first MythTV box a mere three years ago this December.

> Actually, AFAIK, Europe has had MPEG-2 digital TV for a /lot/ of
> years (and much longer than the US).  Again, you're confusing
> digital with HDTV.

Let's examine UK's Freeview (also, as Mike noted, an MPEG2-based
system), since that's the best-known and most-widespread European
over-the-air digital-broadcasting example.

Fact: Freeview deployed starting in the late 1990s, almost exactly at
the same time as the start of the US deployment of digital
broadcasting. It began as a pay service and, after proving to be
commercially unviable, became free in 2002. Freeview is used by about
35% of UK TV watchers, with another 35% or so sticking to analog
over-the-air, and the rest on cable or satellite.

Fact: Freeview offers about 60 TV channels (if I recall correctly),
which is quite a bit more than the about one to two dozen (including
both the primary HD and secondary SD channels, if any, each local
station uses) are going to be typically readily available to the 10%
of Americans that rely on just over-the-air TV (as earlier noted, US
satellite and cable users have typically had hundreds for a decade or
so now) user. This is possible because . . .

Fact: Freeview is *not* HD; it's entirely SD. Not that it's ever
claimed to be otherwise, but savvy Americans who hear of it being a
digital broadcast-television standard are naturally (and, given our
background, understandably) going to assume that it is HD.

Fact: There is insufficient bandwidth within the Freeview system for
HD. There are some very clever methods that have been discussed to
compensate for this, but: a) They are still in the discussion phase,
with deployment still an unspecified number of years away. b) They
will require a move to a new encoding method (MPEG4) *and* a new
broadcasting method (DVB-T2), so yes, both viewers' settop boxes *and*
broadcasters' equipment will have to be replaced (again) when this

Yes, H.264 MPEG4 is more efficient than MPEG2. MPEG4 didn't exist at
all when the US HDTV standard was approved in the mid-1990s. But no,
that doesn't mean that US over-the-air HDTV is somehow hopelessly
behind the rest of the world in terms of picture quality (as Mike
himself well knows, as he has often mentioned how happy he is with
having just OTA HD). My understanding is that MPEG4-encoding
efficiency over MPEG2 is much less so at HD resolutions. In any case,
MPEG2 technology is very easy to decode and play back--requiring
nothing more than a ~3.0GHz Pentium 4 and an Nvidia 5200 video card,
both readily-available gear four years ago--and will continue to
improve on both the broadcast and reception sides. H.264 MPEG4 will
continue to improve as well, but as many reports on this list
indicate, only in the past six months or so have people finally
obtaining the hardware (a Core 2 Duo at ~2-3GHz) and software codecs
needed to reliably play back H.264 MPEG4 broadcasts on their MythTV
boxes. Perhaps someday we'll decide that it's worthwhile to move US
over-the-air broadcasts to MPEG4 for the added efficiency. If so,
American over-the-air TV watchers will have to buy new settop boxes
and over-the-air broadcasters will have to get new equipment, *just
like what the UK is going to be doing in the future*! Where's the
advantage there?

Let me close this with a question I asked last year and will reask out
of curiosity: Who are the non-North American MythTV users that are
routinely receiving *and able to play back* more than one channel that
broadcasts the majority of its in HD? The answer, the last time, was
*zero*. I expect their numbers are non-zero by now, but I do not
expect to be overwhelmed with responses, either.

Frontend:		P4 3.0GHz, 1.5TB software RAID 5 array
Backend:		Quad-core Xeon 1.6GHz, 6.6TB sw RAID 6
Video inputs:		Four high-definition over FireWire/OTA
Accessories:		47" 1080p LCD, 5.1 digital, and MX-600

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