Posted by Bill Fright on 11/12/05 19:36

AnthonyR wrote:

> "Bill Fright" <billfright@austin.rr.com> wrote in message
> news:BEKcf.2527$th3.2217@tornado.texas.rr.com...
>
>>
>>AnthonyR wrote:
>>
>>
>>><marks542004@yahoo.com> wrote in message
>>>news:1131572540.281420.97030@g44g2000cwa.googlegroups.com...
>>>
>>>
>>>>Hi,
>>>>
>>>>This may be off topic - please suggest other newsgroup if applicable.
>>>>
>>>>There was a report on my local TV news about several cable companies
>>>>carrying several TV series on-demand.
>>>>
>>>>Does anyone know the carrying capacity of a cable network for this type
>>>>of thing.
>>>>
>>>>When I was involved with computer networking 15 years ago video
>>>>conferencing always wound up killing the networks.
>>>>
>>>>I know speeds have gone up considerably but there must be a point at
>>>>which the on-demand capacity breaks down.
>>>>
>>>>
>>>>regards
>>>>
>>>
>>>
>>>Not sure on the answer but i thought the same thing.
>>>In fact Time Warner offers me so many OnDemand channels now it's
>>>impossible to watch a fraction every day.
>>>Besides Movies from HBO, Showtime, TMC etc... they offer A&E, CNN,
>>>FoodNetwork, Comedy Central you name it
>>>everything OnDemand now. I don't know their limits but so far everything
>>>runs pretty smoothly.
>>>I wonder after every single customer goes digital, uses broadband and
>>>movies over IP at the same time what will happen?
>>>
>>>AnthonyR.
>>>
>>>
>>
>>To me it's all about the bandwidth. Sure they can cram more programs into
>>the pipe as they continue to lower the quality. Any of you guys who are
>>compressing your high quality shows to mpg2 (DVD) know what I'm talking
>>about. The shorter the show the higher the quality.
>>
>>Maybe I have too much time on my hands or I'm a huge nerd but I love to go
>>to retail home theater stores and talk bandwidth with people. My favorite
>>is to have them show me HD via satellite.
>>
>>So nothing will happen (as far as a major system crash) they'll just keep
>>lowering the bit rate and decrease the overall quality to fit more
>>programming in the pipe.
>>
>>Next time I hear digital quality I'm gonna throw my cell phone at
>>somebody.
>>
>
> Bill Good Point,
> But normally a cable company can squeeze say 800 channels into a cable and
> send that to 8 million people in nyc, right?
> But if all 8 million people ask to see an On Demand Movie or show, each one
> starts and pauses it separately, so now how does the cable company fit the
> 800 channels plus the 8 million movies all playing into that bandwidth,
> squeeze it more?
> wow, that's a great trick if they can pull it off.
>

Okay now I have some home work!!! I'll look into this and figure it out.
But I suspect I know the answer already. I'll bet the on demand programs
reside in RAM type memory and since it can be accessed at different
points simultaneously and the bandwidth is low it will accept several
"demands" at one time. For example if you have a terabit of RAM on a
server you could have people access it simultaneously all a across a
network.

I will look in to this.

> I suspect, they have many distribution points, so each neighborhood handles
> it's own Ondemand bandwidth independently of the entire system, sort of how
> cell phone companies have many cells. But I don't really know, just guessing
> here.
>
> Your comment about "hearing about digital quality" is funny. That's how they
> sell us new stuff, promise better quality to get us to change then deliver
> less. Overhaul it still is better than I was getting with my rabbit ears
> years ago, even with occasional digital breakup. :) I don't miss the snow
> and double images and ghost of analog tv.
> I wonder how much better digital tv transmission will be once they convert
> over?
>
> AnthonyR.
>
>

Exactly, less quality but they sell it like it's the best ever.


You just touched my favorite point. Put a pair of studio monitors side
by side with a waveform/vector scope for each one. If your antenna
receives the analog signal correctly it will have a much higher
resolution than a cable or satellite signal. The key here of course is
the antenna. This goes double for HD. So the answer to your question is
yes, digital over the air transmission is going to suck just like cable
and satellite because it's going to be compressed the same way. So in
2008 when they pull (supposedly) the plug on analog transmission you'll
lose the highest quality you could ever receive at your home as a
consumer. Like the plague mpeg2 is coming to get you!

Perhaps I'm bordering on insanity but the pixilation and blurred
(averaged) back grounds are artifacts I don't find acceptable in a video
signal. Of course my production company delivers mpeg2 products just
like everyone else but I never turn in mpeg2 products for broadcast.

Hell I'm so determined I still shoot on Betacamsp over DVcam even though
it's much less convenient.

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