[opendtv] Re: Frames Per Second of 720P

  • From: Tom Barry <trbarry@xxxxxxxxxxx>
  • To: opendtv@xxxxxxxxxxxxx
  • Date: Sun, 27 Jul 2008 21:03:01 -0400

I have never spent time behind the camera but I think I have to go with John on the framing issue. It seems quite obvious to me that how you best frame the picture will indeed depend upon the expected amount of detail being presented to the viewer.

I have a Sprint HTC phone with a subscription that allows me to watch CNN in (IIRC) a 320x240 resolution on about a 3" diagonal screen, though I suspect the delivery resolution may be less. Anyway, that makes it about 1.75" high in 4:3 landscape mode. I seem to hold that about 15" away from my eyes so I guess that's about a viewing distance of 8.5 screen heights.

Meanwhile CNN is muchly talking heads. And much of the info watching people talk is actually non-verbal, maybe assessing their credibility, intent, or emotional state from various clues visible in face to face communication. But at 8.5 screen heights the ability to see that information far trumps the gain from widening the field of view to provide more context.

Meanwhile, in HD sitting close to a big screen the reverse is true. There is marginal extra value in being able to count pores or nose hairs on the talking heads so instead the experience is enhanced by spreading it out a bit and providing info on a wider area.

I personally think the extreme example of this is in something like soccer, where suddenly the ability to provide the context of the player(s) makes that game much more desirable in HD, being able to zoom out a bit and provide better context without losing the needed detail on the most central players.

The net result is I really do want things framed differently between my phone and front projector.

- Tom

John Willkie wrote:
This is fun!

I can say that some content owners today have the position that they won't
use M/H on their transport streams.  But, they are interested in selling
some of their content to others in the M/H space.  Just like exists today in
other mobile tv spaces.

I can also say that I have personally talked to engineering executives at
several broadcasting group owners that don't own much of the content that
they air -- including one discussion yesterday -- that are very interested
in using M/H, even on the bleeding (expensive) edge.
One engineering executive in the first group told me -- even though his
company's stock isn't doing well -- that broadcasters interested in M/H
think that it will gin up their stock.  Certainly, that's true if the
services take off.

Craig, I'm happy that you think your iPhone screen has more resolution (I
guess you mean pixels) than an NTSC screen.  In other words, it's better
than a circa-1948 receiver, and without the curved edges.  I'm also glad to
hear that while Steve Jobs is sick, he won't tell the details to anyone on
the record, and it isn't a recurrence of cancer.

It is you that is out of touch with the reality.  I've been reading about
and actually watching mobile tv content for several years.  Apparently, you
have not been doing either, or you weren't taking advantage of the better
than NTSC resolution of your iPhone screen.
Without exception, everything I have read about or seen in mobile tv was
either hard to see, or was shot "close-in."  This has been addressed in
much about Apple instead.  I attended a private summit just last week where
this "new difference" was discussed.  I would suggest that you engage in
some reading on the subject -- or better yet -- try to watch "ER" on your
iPhone, to see what happens to 16:9 video when shown on a mini 4:3 screen.

Last time I checked, the responsibility of dps ended the moment they
captured an image to video or film.  They largely are clueless about
realities beyond that.  Remember the ASC trying to halt the DTV transition
because they weren't consulted (and didn't discover) the 16:9 issue until
well into the game?  (They didn't hold things up for even a day.)

At this summit I attended last week, one guy who works closely with dps gave
their concerns as a reason to not do Active Format Description!  That was a
riot, since AFD is the only way to prevent their worst nightmares from being
realized in homes!  They are totally and utterly clueless about the
realities beyond their viewfinders.

But, you are missing the point.  There's a world of difference between
framing an XCU (extreme close up) for dramatic effect and making a whole
presentation that way. One of the first content companies to present their content in mobile tv was
MTV, in the form of MTV Mobile.  They found within a few broadcasts that
they couldn't just repurpose their standard content because 1) the images
were just too small to see on small screens and 2) the :30/:60 form was just
too long for mobile video, where people just don't have the linear time to
watch that length of content.

You have heard of the concept of 'webisodes', haven't you?
You think Google is working on an electronic service guide?  Who the hell
cares?  They aren't involved in any standards-development work that I'm
familiar with.  They are working on much, but much of that never is released
to market, or is late (Android) or very difficult (Android) to work with in
the real world.

That's why standards are important, with the involvement of all parties in
the ecosystem; most of the issues are worked out in the development of the
standard, not months after the press releases when outside engineers try to
make your mush work.  If there are issues, the process insures that all
parties will know about it and will work to resolve the issues on a
multilateral basis.

Google is also working on TV advertising systems.  I even get web hits from
goggle.com web sites on MPEG-2 syntactical elements.
Here's something to keep in mind: even though I use Google for web site
statistics, when a google.com employee searches for something on my web
site, they are never able to discern the geographic location?  In other
words, they'll tell me much information about routine web site searches, but
they "don't know or won't tell" the location of their employees.  And, since
you may not be experienced with Google Analytics, I know the difference
between a google gulp of my web site (which they don't report to me,
either), a search that came through a google web site, and a search that
came from a google employee.

I'm a fan of google.  While they know quite a bit about you, they prevent us
from knowing much about them.  What a fun attitude!

Worse than the number of standards is "non-standards" like Android.
Middleware that supports standards on both ends is a good idea.  Otherwise,
you end up (like Android) plowing two fields at the same time when it comes
to implementation.

Here's a prediction:  If Google wants to play in the ATSC ESG or M/H space,
they will have to become a customer of or will have to purchase one of the
four or five companies that appear to be positioned to serve the space.  Or,
since they are not listed on this page http://www.atsc.org/atscmembers.html
they will most likely be way behind.
Come to think of it, I need to prepare web pages for M/H syntactical and
semantic elements so I can unveil them when the time comes.

John Willkie
-----Mensaje original-----
De: opendtv-bounce@xxxxxxxxxxxxx [mailto:opendtv-bounce@xxxxxxxxxxxxx] En
nombre de Craig Birkmaier
Enviado el: Sunday, July 27, 2008 7:09 AM
Para: opendtv@xxxxxxxxxxxxx
Asunto: [opendtv] Re: Frames Per Second of 720P

At 10:07 AM -0700 7/26/08, John Willkie wrote:
It's totally absurd to mention the deprivation of legacy receivers in this
context; it's like asking "how will color cameras affect black and white
television sets?"


The important question to ask in this content is what is being done to enhance the the ATSC standard for fixed receivers in the home? Or to be more precise, will broadcasters support any enhancement that will not work for legacy receivers?

Clearly, h.264 is a desirable enhancement for both the new M/H service and for fixed receivers. One must ask whether broadcasters will use this codec for full resolution HD broadcasts, knowing that legacy receiver will go black (or blue screen).

Let me give you an example that I can talk freely about.  When you shoot
small screens, you "shoot bigger" than when you shoot for a large screen.
When shooting someone's face, you would tend to make their face fill more
the screen than if you were shooting for a large, or even room-filling

This illustrates how out of touch you are John. My iPhone screen has more resolution than most NTSC displays. I seriously doubt that image capture and framing techniques will change because of mobile. By the way, I used to think that way about the web on mobile devices, until Apple solved the problem, making it possible to view ANY web page on a small screen.

But this does not prevent some content creators from building web pages optimized for small screens, just as there will be a new genre of short form video for mobile devices.

So, if you think that there's much utility in showing a screen-filling face
on a large, room-filling tv set, rock on. \

Apparently many directors of cinematography have no problem filling a movie screen with a face...

All standards are out of date in this time frame at the time they are
adopted.  But that's not the real problem with standards.  "I love
standards, there are just too many of them" is the real problem.  But,
thankfully, there is only one standard for digital tv transmission in the


The ATSC standard uses h.262 encoding for video.

DirecTV and DISH are using both h.262 and h.264 encoding for digital TV transmissions.

Apple is using h.264 for selling and renting TV shows and movies to the

Others are using Windows Media for digital TV.

And Flash is being used by YouTube and others.

I guess John is just focused on terrestrial broadcasters, who now capture less than 1/3 of the digital TV audience (full day ratings, not just prime time).

And did I mention that the new ATSC mobile standard has competition too...

Back to the ESG (electronic service guide).  Wouldn't it be cool if the
devices all over the world could employ the same bits to render an ESG?  If
that ESG would work over the web, over the air, and be usable on WiFi
devices, mobile phones, web browsers, wireless routers, etc. etc., and be
able to provide programming information on broadcasts, regardless of
modulation or channel coding?  There is already such an electronic service
guide system, and I could even talk about it without violating the ATSC
But I won't.  "Already" might be an exaggeration, but only by a few weeks

I think Google is working on this...


If you think that 8-VSB is more efficient than a modulation scheme that you
know nothing about, one wonders about your sanity.  It seems to me that,
since the payload of any modulation scheme for tv is largely carrying video
(something like 95% or more of a program service is video) that the more
relevant figure is the efficiency of video compression and how that is
packetized.  I suspect that you don't mean to imply that MPEG-2 is more
bit-efficient than MPEG-4.\

Uhhhhh John...

8-VSB is significantly more bit efficient than any of the proposals for mobile/hand held. Depending on the constellation that will be used there will be an additional 25% to 50% bit penalty for the ruggedized modes of the mobile standard.

What I MEANT TO IMPLY - actually I clearly stated it - is that it would be possible to offer a movie download service that would deliver the bits using 8-VSB to maximize bits per hertz, and also use h.2645 for encoding, which would maximize compression efficiency relative to MPEG-2.

Obviously, no legacy receiver would be able to view these movies, but that's OK.

I said this in the context that some manufacturers will most likely build the new ATSC enhancements into their fixed receivers. This will allow these fixed displays to use all of the new services offered for the mobile/hand held market, and to decode h.264 bitstreams that can be delivered with 8-VSB, the M/H modulation, a DBS broadcast, cable in the near future, and Internet download. This assumes that the M/H standard will use h.264, which I believe to be a safe assumption at this time.

I doubt that a broadcasters would be concerned about the incompatibility of legacy receivers with h.264 bitstreams delivered using 8-VSB, if these bitstreams are a separate paid service like Moviebeam.

I think that it's unlikely that "new receivers 'may" be able to take
advantage of the new mobile bits to improve their ability to tune to any
channel "  The ATSC M/H process had three different modulation/coding
schemes to consider.  I know not much about the Thomson proposal, and I
haven't bothered to look it up.  I know a bit more about the Harris/LG MPH
proposal, and I know quite a bit about the A-VSB proposal thanks to one R&S
engineer I talked to at NAB that provided me with an 8mb powerpoint
presentation.  (And, I've talked with several Samsung consultants over the
years that their proposal has been pending.)

What has ANY of this to do with the possibility that ATSC M/H features may be incorporated into future fixed receivers?

To the best of my knowledge, nothing in these proposals would have aided
ability to tune into any legacy programming.  Indeed, if we are talking
about the early phases of the A-VSB proposal, it would have lessened if not
merely prevented the ability to tune into legacy broadcasts.

This is NOT my understanding. I have been told that several of the techniques that are being evaluated for the M/H standard can also be used to help guide the equalizer in the tuner, even if the goal is to capture an 8-VSB portion of the modulated signal. Time will tell.

From what I see today -- and not knowing about the layers of approval
this stuff becomes public -- ATSC M/H is a "whole new ballgame."

Hmmmm... I believe I said much the same thing, and was reprimanded by Mr. Aitkin:

"Where did you get the notion that almost everything had to change?"

I would also note that just about any improvement in digital modulation or
coding (DVB-H, DVB-T2) doesn't work with well, if at all, with legacy
receivers.  So, that ain't an ATSC issue per se.

The nature of extensibility is to add to existing functionality without breaking it. This allows us to continuously upgrade consumer devices to do new things, but not break existing devices - you just need to upgrade if you want the new stuff.

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Tom Barry                  trbarry@xxxxxxxxxxx  

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