Non-TiVo OTA Question

[atmuscarella]

Hello All,

My local ABC station (Rochester NY Channel 13.1) broadcasts the CW network on 13.2 up until recently the CW network was in SD (TiVo showed it as 480i).

Last night I notice that the CW network looked like it was in HD (full screen, better picture etc.). So I checked and both 13.1 & 13.2 now show they are both being broadcast in 720p.

I thought there was only room for one HD stream per channel - I guess that is not true? Or is it likely that the channels have been compressed somehow? Anyone else see two HD streams on one channel?

Thanks,

P.S. Nikita looked great in HD!

[vectorcatch]

It mainly depends on the bitrate per channel. You could have 20 HD streams in one channel if they were all at 1mbps (It would look terrible, but you could do it).

I can't remember what the max is per channel, but they just can't add up to more than that. Most likely it is not an even distribution between the 2 channels.

[ThAbtO]

I think you can have 4x 480i per stream bandwidth, 4x 480 = 1920. Here in the San Francisco Bay area, our Channel 7 now have 2x 720p (7.1, 7.2) and 1x 480i streams (7.3) and doing the math, it also comes up to 1920.

[turbobuick86]

While the local networks (Los Angeles) don't broadcast hd on their sub channels, the PBS stations do it often. At least 2 PBS stations are running 3-4 subs each. They might allocated more bandwidth?

[Series3Sub]

Actually LA local KABC channel 7 does broadcast an HD service at 7.2, the Living Well HD channel. Also, Fox 11 has has down-mapped a sub-channel from KVEA to Fox 11.3, which is the same content as main 11.1 and in HD. 11.2 is same content as 11.1 but in SD.

Oh yeah, there is room for however many HD services they want on the ATSC OTA digital broadcasts. However, as a previous poster noted, there are going to be some serious compromises to the bit rate resulting in noticeably poor and even irksome picture quality. KABC 7.2 Living Well HD lack detail and can be riddled with pixel break-up . Even main 7.1 has suffered from rare pixel break-up because of trying to squeeze another HD in the multi-plex leaving 7.3 looking like old time analog crappy PQ. And Fox 11.3 (really KVEA) in HD is noticeably inferior to the main 11.1 with soft PQ lacking detail and color saturation but no break-ups. The broadcasters are just pushing the limits. It is clear they are trying to squeeze an additional HD on the multiplex, but it looks terrible.

[justen_m]

In Boise, we've got on our PBS
4.1 480i
4.2 720p
4.3 480i
4.4 480i

Also, there is another channel that is
7.1 1080i
7.2 480i but in 16:9
7.3 480i

edit: this is all OTA

[classicsat]

One of the mid-Michigan university stationds I sometimes get (WDCQ Bad Axe, I recall) is something like that Boise PBS. I don't know about Boise, but that station's "HD" channel is 4:3 720P.