[jfgabel]

I previously had gotten my local HD channels from an over the air antenna. The pictures were very sharp and I received more than one comment regarding how good it looked. Because of my job I moved to another city and the only way I could get programing was either thru Direct TV or Cable One. I opted for Direct TV.
I have noticed that the quality of the picture isn't nearly has good as it was from the regular antenna. I assume this is because of the compression. I have thought about giving Cable One a try since they seem to have a bunch of bandwith. I currently get 50mb for my internet service from them.
I am curious if anyone has ever looked into this type of signal degradation and which one would most likely be the better solution. Direct TV or Cable One.

 

[PrinceLH]

I previously had gotten my local HD channels from an over the air antenna. The pictures were very sharp and I received more than one comment regarding how good it looked. Because of my job I moved to another city and the only way I could get programing was either thru Direct TV or Cable One. I opted for Direct TV.
I have noticed that the quality of the picture isn't nearly has good as it was from the regular antenna. I assume this is because of the compression. I have thought about giving Cable One a try since they seem to have a bunch of bandwith. I currently get 50mb for my internet service from them.
I am curious if anyone has ever looked into this type of signal degradation and which one would most likely be the better solution. Direct TV or Cable One.

Not sure whether Cable or Directv is a better option. Both would compress the signal, unlike Over The Air. I too saw the difference, in my local channel signals, when Directv lit up my local channels, 3 months ago. The Over the Air signal was so much better.

 

[Xsabresx]

Someone once explained to me that they (the locals) lose PQ because their signal is split between the main channels and all of the sub channels. My NBC and CBS are fine, but my ABC PQ is atrocious. Lots of ghosting in their prime time shows.

 

[veryoldschool]

"Compression" is often miss-used.
A few things here:
I have my local from DirecTV and over the air, so I can do a real A/B of the exact same program.

Can I tell a difference?
yes, but barely and the difference is hard to describe.

All digital programing, be it over the air or SAT, has compression, so the real question is how much or is it over compressed.
DirecTV uses MPEG-4, where OTA uses MPEG-2
DirecTV send "full resolution", which most cable and Dish doesn't. Dish sends 1080i [1920 x 1080] in 1440 x 1080. "Most cable" does similar things because their bandwidth is limited, while DirecTV isn't/ or has more.

The difference I do see is directly related to the MPEG-2 to MPEG-4 conversion "I think", as I really need to look close at very fine detail to even think I see a difference.

 

[veryoldschool]

Someone once explained to me that they (the locals) lose PQ because their signal is split between the main channels and all of the sub channels. My NBC and CBS are fine, but my ABC PQ is atrocious. Lots of ghosting in their prime time shows.

While sub channel do eat into their 19.3 Mb/s bandwidth, CBS & NBC here are 1080i, while ABC & Fox are 720p, which doesn't use as much bandwidth.
"PQ" can be getting lost as it gets to DirecTV.

 

[Xsabresx]

Here is the thread I started a while back where they mentioned the sub-channels.

http://www.dbstalk.com/showthread.php?t=191282

Keep in mind that DirecTV is rebroadcasting your LOCAL affiliate. The network may be sending a pristine image that your local channel is compressing to death or otherwise screwing up. DirecTV can't make a bad source look good.

Many local affiliates are running subchannels, sometimes multiple subchannels, on their OTA bandwidth, which will reduce quality for everyone, as most local feeds are picked up for satellite via OTA antennas.

True enough but I have two ABC affiliates available to me and I see the same problems on both. As I have doubles of the major nets (ABC, CBS, Fox, PBS and Comca....NBC) I will usually check them both when there is a problem.

This is very true here in SoCal. KABC has 2 720p channels (7.1 and 7.2 LiveWell) as well as 7.3 (Weather and News). Since they started showing LiveWell in 720p, MacroBlocking has been a major PITA. Shows the same from OTA as well as DirecTV. Sucks! I wish the broadcasters would be limited to 1 sub channel and make it 480i only. KCBS and KCAL (local independent, but owned by CBS) here always looks the best, as they are not using any bandwidth for sub channels.

^^^
Amen - my CBS (KYW - Philly) has zero subchannels and has much better PQ than other locals. More subchannels = poorer picture quality. More subchannels = greater profit.

Guess what'll win?

 

[sigma1914]

It varies by area. Here in the Dallas DMA, the locals via satellite are very good. NBC used to be crappy a few years ago, but it's great now.

 

[Go Beavs]

At my home, I get my locals via DIRECTV and OTA from Portland. I've tried A/B comparisons and, for me, I think the DIRECTV's version looks better.

I can't be sure, but I remember reading somewhere that in Portland, DIRECTV picks up OTA via fiber, not from an antenna. If that's the case, then getting the raw feed and compressing it into MPEG-4 should be higher quality than converting MPEG-2 to MPEG-4.

 

[Xsabresx]

My ABC has never improved. In my original thread I said they looked like they had been done with water colors. That pretty much sums it up. Obviously the local ABC affiliate here. No other channel looks like they do.

 

[CCarncross]

OTA, unless there is something wrong, should always be a little better, OTA comes to you via MPEG-2 and does not get converted to MPEG-4. I have a few friends that live in areas that do have both SAT HD LiL and OTA and most choose to watch OTA for the slight edge in PQ. The LiL HD channels via sat are usually slightly softer, theoretically there is no way they should be better though as they do go through an additional conversion process in most all cases. Sub-channels in theory always degrade the main channels PQ due to all the bandwidth not being used for the .1 or -1 if you will channel. Stations that are using more than one sub-channel are obviously the worst. PBS is notorious for having more than 1 sub-channel, in my DMA, they have 3 sub-channels and PQ does suffer substantially. Theoretically in a DMA that has several sub-channels for a digital station, if D* is only carrying the primary channel, it could be better because they could be getting only the primary feed directly via fiber from the station, it just depends on the station and its delivery method to D*.

 

[skatingrocker17]

To me, 1080i DirecTV and OTA looks very similar but 720p stations like ABC look a little better through DirecTV. The only explanation I have for this is that the picture is soft thus covering up artifacts on DirecTV, it 720p might not look as sharp but overall it looks a little better in my opinion. I'm only referring to WTVG 13ABC, I haven't tested other 720p stations like FOX.

 

[Davenlr]

OTA, unless there is something wrong, should always be a little better.

All depends how the signal gets to you.

We have a two stations here, with multiple subchannels, that look pretty bad at times, especially during sports, via the antenna. They look great on Directv...because both stations are sending the DirecTv receive site a fiber feed directly from their master control room before its multiplexed with subchannels.

In all actuality , the best PQ is from the network feed on C band, (or KU for NBC and PBS). With the exception of FOX which scrambles its feeds and is only available from two sources using satellite to link to remote transmitters, all the networks HD feeds are available (in all time zones).
Watch NOVA on PBS's KU feed, and you will see quality.

 

[charlie460]

WABC 7 NY looks absolutely AWFUL on DirecTV. I'm not sure if it's low bitrate at the station but it just looks awful. WNYW Fox 5 NY looks pretty bad too. Both 720p stations. They do look better OTA. Some sharpness is lost in the MPEG-2 to MPEG-4 encoding as well.

 

[CCarncross]

All depends how the signal gets to you.

We have a two stations here, with multiple subchannels, that look pretty bad at times, especially during sports, via the antenna. They look great on Directv...because both stations are sending the DirecTv receive site a fiber feed directly from their master control room before its multiplexed with subchannels.

Hence my last sentence, while not as technical an explanation as yours, I believe I was saying this very thing.

Theoretically in a DMA that has several sub-channels for a digital station, if D* is only carrying the primary channel, it could be better because they could be getting only the primary feed directly via fiber from the station, it just depends on the station and its delivery method to D*.

 

[Davenlr]

Missed that, sorry.

 

[P Smith]

At my home, I get my locals via DIRECTV and OTA from Portland. I've tried A/B comparisons and, for me, I think the DIRECTV's version looks better.

I can't be sure, but I remember reading somewhere that in Portland, DIRECTV picks up OTA via fiber, not from an antenna. If that's the case, then getting the raw feed and compressing it into MPEG-4 should be higher quality than converting MPEG-2 to MPEG-4.

Doesn't look right - what you means raw ? 10 GBps ? no compression at all ? by fiber ? Without the info, you can't deduct so much as you wrote above.

 

[evan_s]

I have to agree. A raw uncompressed hd signal is unlikely because of the massive bandwidth that would require. They are probably getting a higher quality mpeg2 compressed stream. I want to say that I read somewhere that it was usually around 40 or 50 mbs.

 

[Jason Whiddon]

Ive lived in 3 markets over the last 5 years, in all OTA was superior to Dish/Directv HD. In some markets one channel was better OTA than another, but it all boiled down to subchannels. Our CBS here SUCKS. Whenever football is on the stands are a blocky mess, and its just worse on Directv so its not their fault. The local CW had about the best PQ because they had no subchannels, but they added one and now my Supernatural PQ noticeably went downhill.

I use OTA as much as possible, because the sat hd versions are just soft when comparing. Its not bad, but there is a difference.

 

[Go Beavs]

Doesn't look right - what you means raw ? 10 GBps ? no compression at all ? by fiber ? Without the info, you can't deduct so much as you wrote above.

I have to agree. A raw uncompressed hd signal is unlikely because of the massive bandwidth that would require. They are probably getting a higher quality mpeg2 compressed stream. I want to say that I read somewhere that it was usually around 40 or 50 mbs.

Yeah, using the word "raw" probably isn't very accurate. I think evan_s is on the right track but I'd love to know the real answer.

I think this pretty much sums up my post:

I can't be sure, but I remember reading somewhere that in Portland, DIRECTV picks up OTA via fiber, not from an antenna. If that's the case, then getting the raw feed and compressing it into MPEG-4 should be higher quality than converting MPEG-2 to MPEG-4.

 

[veryoldschool]

I think evan_s is on the right track but I'd love to know the real answer.

While the network "backhaul" [maybe not the correct name] has been reported to be in the 40-80 Mb/s range, since it doesn't have any of the local [ad] inserts, I really doubt this is what is being sent to DirecTV.
Transmitters are usually not co-located with the studios, so it makes sense that a fiber feed to DirecTV is merely what is also being sent to the transmitter.