[Wayne]

ACCESS is owned by CTVgm, so they would benefit from the the savings.

Sorry I was projecting my Ontario bias onto this. I knew that Access is a an educational channel and that it was therefore likely owned by the provincial government - just like TVO is owned by the Ontario government.

 

[roger1818]

The only sub-channels I would support (in urban markets anyway) would be audio services.

Yes, that would be nice. How about low frame rate SD video? An example of this would be a traffic cam refreshed at say 2 frames per second. This should be good enough to serve its purpose (seeing if cars are moving) yet it shouldn't use up very much bandwidth. I know the ATSC standard doesn't technically support this frame rate, but it could be faked by providing a new image every time there is a frame redraw (I think it is twice a second), and saying there are no changes to the image between them.

 

[Billsmith]

Thank you for your responses on the above topic! I didn't personally experience any macro blocking when watching the Olympics over CFCN-DT but then I receive a good signal from the CFCN tower (76 - 82%).

I also understand that people are saying that the OTA quality is better than the equivalent cable or sateilite and that macro blocking is an issue here in North America. The UK is using DVB which uses an MPEG format which seems to give good clear moving pictures OTA at least to my eye.

I suppose that underlying question is what is visually perceptible on the HD channel versus the bandwidth required and associated costs for secondary programming?

 

[Wayne]

An example of this would be a traffic cam refreshed at say 2 frames per second. This should be good enough to serve its purpose (seeing if cars are moving) yet it shouldn't use up very much bandwidth.

There's an app for that (I have it installed on my iPad)!

The problem with using TV channels for this is that it would use up dozens of sub-channels if you wanted to provide decent coverage, at least for Toronto.

 

[Billsmith]

Yes Wayne - for traffic maybe but what about things like airport local flight arrivals and departures or local weather maps??

 

[stampeder]

Reminder on some facts

The ATSC digital OTA broadcast system, using 6MHz channels, allows broadcasters to slice-and-dice each channel in a variety of ways between television programming and data. Post #15 in the OTA FAQ gives a detailed explanation of sub-channels and bandwidth issues.

If you didn't know that, now you do.

As for whether to do it or not, roger1818 reminds that Canadian policy is for major market DTV stations to use their maximum bandwidth for a single channel.

The CRTC has opened the door to co-located rural DTV transmitters, in which a group of broadcasters may share tower and channel space. Whether that means discrete full bandwidth HD channels, discrete bandwidth-reduced HD channels with SD sub-channels, or one SD channel with SD sub-channels remains to be seen in policy and practice.

Now, speaking purely as a consumer, I applaud that major city DTV broadcasters must use their full bandwidth for their single channel. The visual benefits to the viewer are not arguable. It is not necessary for DTV broadcasters to slice up their bandwidth allotments with info that can easily be found elsewhere.

 

[roger1818]

Whether that means discrete full bandwidth HD channels,

This is already being done in urban areas (IC is encouraging shared towers and antennas where ever possible) so I doubt if the CRTC means this for rural areas as approving it is a given. They specifically say multicast services, which to me means more than one broadcast per 6MHz channel. This could be two bandwidth reduced HD broadcasts or any of the other combination of HD and SD broadcasts you mention on one (or possibly more) channel. Who knows, they may even experiment with using MPEG4, though that would mean consumers having to buy new tuners.

 

[Billsmith]

roger1818 reminds that Canadian policy is for major market DTV stations to use their maximum bandwidth for a single channel.

Where is this policy written?

Personally I also prefer the best picture definition possible and so have no argument against this however the rule is rigid in that it doesn't give marginal stations in major markets any chance of lowering their operating costs by means of channel sharing. The US as far as I can now see benefits greatly in their major markets by doing exactly that - e.g. different languages and a greater variety of programming. The UK also does the same thing in it's major market areas via DVB-T multiplexers neatly organized in the UHF band. They are also assigning a dedicated multiplexer for HD channels only using (DVB-T2).

 

[stampeder]

I could search for it but suffice it to say that we didn't make it up. It is a CRTC policy.

 

[Billsmith]

Mmmmmmmm - seems that the rural areas have been given a break in some regards. Sounds like a possible vote getter - more channels available for the rural areas perhaps at lower cost?

 

[roger1818]

Where is this policy written?

Post #6 in this thread has a link to the policy. Since then the CRTC has encouraged multicast services outside of the core markets as a way of making the transition to DTV more affordable for the broadcasters, but i expect this original policy still stands in the core markets.

 

[iceman2g]

Don't know if this has already been suggested, but how about TFO. I imagine it would be a digital subchannel for TVO in areas where TFO doesn't have it's own transmitter.

 

[x4mer]

Isn't TFO cable only?

I didn't think it had any OTA transmitters.

 

[stampeder]

It fits with the topic of the thread - its an idea...

 

[iceman2g]

It has several transmitters, it's owned by the government of Ontario.

I also think Ontario Parliament Network (CJOL) would be good candidate for a subchannel. The fact that its OTA broadcast is limited to Northern communities is a disservice to other Ontario residents. I understand it's available on cable and via web, but I think there has to be consideration for those who don't have cable or satelite and may have limited internet connection.

 

[little-infinity]

Well it really depends whether TVO programming goes HD. From what I see nothing is really HD, though perhaps shows like Midsomer Murders and their primetime would go HD.

Perhaps something like this:

19.1 would be main TVO programming
19.2 would be nice for like a TVO-kids all-day thing. (kinda like qubo)
19.3 would be Leglislature.

TFO could use a transmitter on it's own in Toronto. I swear didn't the CRTC have an allotment for CHLF at one point on the CN Tower?

Only wishful thinking though. Of course if TVO content goes HD, I withdraw the above statements. (Though WGRZ's HD doesn't seem to suffer much from its' 2 subchannels).

 

[roger1818]

Perhaps something like this:

19.1 would be main TVO programming
19.2 would be nice for like a TVO-kids all-day thing. (kinda like qubo)
19.3 would be Leglislature.

They probably don't need separate sub-channels for TVO-kids and Legislature. TVO already has kids programming daytime and the Legislature would be off air at night so one sub-channel could be used for both.

 

[Walter Dnes]

Sun TV (a Quebecor subsidiary) might consider carrying http://cnews.canoe.ca/CNEWS/MediaNews/2010/06/10/14334401.html a rumoured news network. What's really sad is that here in Canada, they have to go begging to the CRTC. In the US, they'd get their affiliates lined up and "just do it".

 

[Billsmith]

Yes - I agree the rules that the CRTC come up with seem a little over-cooked and seem to be in favour of certain member´s interests. A shame isn´t it?

 

[arc23]

use of dtv subchannels in canada

i know there may be crtc rules involved

has any station used or tested them [even for a few hours] ?

any channels broadcasting alternate audio feeds in canada?

it seems like to add a full subchannel you have go through a relicensing that nobody has bothered