Question about HDTV broadcasts

[Staples]

I have had a HDTV since March. It has an integrated tuner and I have always watched HDTV broadcasts OTA. The compression that is used is terribly prone to motion pixelation (not artifacts like now days video compression). I always hear of cable companies adopting MS technology, assumably WMV9 which looks great at 5+MBps (less than DVD bit rate). We only have TWC around here but I would assume their compression for digital cable is better then that of what the HDTV OTA broadcast uses. I assumme this because I would imagine OTA is older. Regardless of what they use, if my HDTV broadcasts streamed over their feed, would it look any better than what I currently get?

The two scenarios I see are

1) They get a really good picture (compressed only lightly with a current codec or even RAW) and then compress it with whatever they use and then feed it to their subscribers.

or

2) Their source is only as good as the OTA, uncompressed and then recompressed into their format and then fed to their subscribers.

Does anyone know how it works? If it is the first scenario, there is a chance I would get a better picture over TWC but if it is the second as I suspect, there is no way I can get a better picture than I already am.

 

[jocycliff]

I don't claim to be an expert here and have never tried OTA. But I am on TWC and have a Samsung Direct View HDTV. The HD channels from TWC are spectacular.If you visit avsforums there is a section on the forums for People in your area to post pic quality and what not.

Hope that helps

 

[Staples]

Cool, I'll check it out. The picture of OTA looks great but if there is a lot of movement, the picture can get pretty ugly for a short period of time.

 

[Apex]

Cable compression (currently) tends to be worst than OTA.

 

[Staples]

Originally posted by: Apex
Cable compression (currently) tends to be worst than OTA.

But I really want to know, what is the source that TWC gets. Obviously they compress it with whatever codec they use but if their source is the same signal that I get OTA to where they just uncompress it and then recompress it, then there is no possibility that I could possibly get a better picture over cable than I already do OTA.

 

[0roo0roo]

adopting wmv9 would require new decoder boxes. and high power ones, wmv9 decoding is hardwork

 

[Amused]

In my experience, OTA is always the least compressed, then cable, then sat.

Although, on NBC last night with the Olympics, I did notice some macroblocking that made DirecTV HD look good in comparison. I dunno if NBC national, or my local was compressing the image.

Also, how much OTA is compressed depends largely on your local stations. By that, I mean how many sub channels do they have? Our ABC has one weather sub channel and it still looks pretty good. But I have heard stories about local stations having many sub channels and seriously compressing their HD channel to do it.

I would go to AVSforum and ask around about your local area. It could very well be that your locals are running many subs and thus are overly compressing the HD. If that is the case, the carrier of your signal will be irrelvant as the signal is compressed at the source.

 

[conjur]

Head to http://www.avsforum.com/avs-vb and go to the Local HDTV Info and Reception forum.

Your local station may not be broadcasting at the full bitrate. Do they have subchannels? That can affect PQ.


Here ya go:
http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=137205