[opendtv] Re: Google And Verizon are Setting Our Public Internet Policy
- From: Craig Birkmaier <craig@xxxxxxxxx>
- To: opendtv@xxxxxxxxxxxxx
- Date: Fri, 13 Aug 2010 07:59:36 -0400
At 3:21 PM -0500 8/11/10, Manfredi, Albert E wrote:
The FCC decided the system would be digital, true, but the
significant part was that the system had to be spectrum compatible
with existing TV, and that HDTV was to fit in the existing 6 MHz
channels. This was decided in 1991. Previous analog systems had
opted for two 6 MHz channels, and there had also been earlier ideas
about 6 channels of satellite-only delivery for HDTV. All of which,
to me, were non-starters.
Yes I left this out of the original message and add this detail in my
reply to Dale.
You have said this before, and I just don't understand how it can be
true. So, not being able to believe it, I checked briefly.
Even before the SDTV modes were added formally, the Grand Alliance
had defined the 720p24 and 720p30 modes. Certainly by August 1994,
when the article was published in the IEEE Transactions on Consumer
Electronics. It is highly unlikely that any EE worth the paper of
his degree would not have known instinctively that these lower modes
were to free up bits for other programs, Craig. In the early and mid
1990s, all this digital network stuff was very well understood.
720P is an HDTV mode. it was included as part of the "Grand
Compromise," which took place in 1993 when the Grand Alliance was
formed from all of the companies that submitted digital HDTV systems
(NHK, which proposed an analog system was left out in the cold).
I was a member of Working Party 4 of the FCC Advisory Committee on
Advanced Television Services, which evaluated all of the proponent
systems for Interoperability, scalability and extensibility at the
behest of Chairman Sikes. This work led to the formation of an ATSC
working group on progressive scanning.
The history behind this is that Mike Liebhold, head of the advanced
technology lab at Apple, and several groups at MIT including the
Media Lab (Negroponte) lobbied Sikes to create an open DTV standard
that would be compitible with emerging technologies from the computer
industry. It is worth noting that Microsoft was not on the radar, and
did not get involved with HD until the 11th hour in 1996.
I worked with all of these people when we wrote the Report of the
Task Force on Digital Image Architecture at the behest of the IEEE
and SMPTE. THis report was the primary input document to Working
Party 4, You can find a copy here:
http://www.pcube.com/pdf/Report%20of%20the%20SMPTE%20TFDIA.html
We were advocating a number of principles that were eventually
adopted into the standard. One key principle was that ALL formats
should be progressive scan with orthogonal (square) pixels.
The Japanese (NHK, Sony and other companies) were adamantly against
this as they were trying to get the U.S. to adopt their 1125 line
interlaced HDTV system. The ATSC progressive scan task force was a
real hoot. This was the first time I actually witnessed very
competent engineers lying to support their corporate interests. I
]won't go into the details here as there are gigabytes of OpenDTV
list archive where we have argued the same issues.
But we almost succeeded in getting rid of interlace in 1993. The MIT
Media Lab sponsored a conference on progressive scanning on Cape Cod
and we left that conference believing that interlace would be
eliminated from the standard.
The Following week the Grans Alliance was announced along with the compromise:
From Wikipedia
- Flexible picture formats with a header/descriptor approach,
allowing the inclusion of both 1050 and 787.5 raster formats.
- Progressive scanning and square pixel capabilities in both raster formats.
- Interlaced scanning and rectangular pixel formats.
- Video compression based on MPEG-2, with additional syntax elements
that represent
- A packetized, prioritized data format, providing flexibility of
services and extensibility.
Actually the Wikipedia entry is incorrect.
In order to meet the spirit of the new standard, NHK and Sony agreed
to modify the 1125/60 system, increasing the number of active scan
lines and using square pixels. This led to the 1920 x 1080 format
that is in the standard today.
I would also add that we asked for the ability to deliver any
progressive format and the ability to carry a multiplex of programs
among other system features.
And even further back than that, in the February 1992 issue of that
same Transactions, explaining how, in the 20 Mb/s channel, one could
fit more program streams. Here is a quote from an article by B.W.
Beyers, of Thomson (one of the GA companies).
"It is likely that a new standard will include not only HDTV
resolutions at 1440 X 960 pixels, but also an NTSC like standard
resolution at 512 X 480 and a VHS like low resolution of 352 X 240.
This will allow a wide variety of data rates and services per 6 MHz
channel."
Yes, it was well known that a digital system could deliver multiple
resolutions and that it could carry a multiplex of programs. This is
EXACTLY why the ATSC and Grand Alliance were so adamant that the
system would ONLY be HDTV, as this would require the full 6 MHz
channel.
The Advisory Committee, ATSC, NAB and MSTV were scared that inclusion
of SDTV formats would cause Congress to reduce the channel allocation
to 2 MHz, which would have been adequate to deliver SDTV.
Therefore - and I can produce documents to verify this - the Advisory
Committee and the ATSC publicly stated that the system would be HDTV
ONLY, with the formats announced by the Grand Alliance. We were NOT
ALLOWED to discuss or submit any documents related to SDTV or
multiplexing while the final standard was being completed in tested
between 1993 and 1995.
By 1995 it was clear that Congress would authorize the DTV service
loaning each broadcaster a second channel for the transition. The
legislation was working its way through Congress in 1995 when the Fox
Network (and others) went to Chairman Hundt and asked that the
standard include the ability to multiplex SDTV formats with HDTV.
Hundt supported this and the ATSC - very quietly - set up a working
group to recommend the specifics of the SDTV formats.
I caught wind of this at the SMPTE Conference in San Francisco in
February of 1995, and shortly thereafter I was contacted by the
Chairman of the ATSC working group to provide him (privately) with
input; please note that there was NO public announcement of the
existence of this working group until we raised a stink and got the
ATSC to accept outside proposals. This took place in July of 1995 at
the law offices of the Advisory Committee Chairman Richard Wiley.
The meeting was to last two days so that all of the proposals could
be discussed. We met in the morning and were informed that each of
the proposals would be given five minutes for their presentation. We
broke for lunch expecting to come back and begin discussions.
Instead, the GA members met with Wiley over lunch. When we came back
from lunch they announced Table 3 and sent us home.
So, I do not know who you were listening to, Craig, but engineers
and the GA were fully aware of the possibilities long before 1995.
And I don't know what you're smokin Bert, because my original
statement that set off this argument was:
After that the FCC did little more than act as a cheerleader. And
Hundt helped the Grand Alliance by pushing for multicasting in 1995,
after it was obvious that Congres was going to authorize the new DTV
service. Up to that point the GA was steadfastly AGAINST standard
definition video formats and multicasting, because they were
concerned that Congress might reduce channel allocations to 2 MHz -
enough to replicate the NTSC service that was being replaced.
Truth is, Bert, that we were largely responsible for making the FCC
aware of the possibilities in 1992 via the Task Force DIA report. We
were also responsible for the FCC removing Table 3 from the standard,
although ultimately the CE industry just did it anyway to protect
thier royalty streams from the standard.
Regards
Craig
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