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Legend in his own mind...
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stuart628 said:
I think you need to check the new mpeg4 locals, they look very comparable to OTA, I believe Directv is on the right path with their HD. Sorry you had a bad night, were you a usc fan?
Actually now they're horrible as compared to OTA. Tearing, macroblocking, checkerboarding... They're better than SD, but nothing like OTA.

And has anyone noticed that the MPEG4 encoders don't know how to keep a color reference? The colors, especially blue/greens, shift ever so slightly every few seconds. It's very noticable on a football game, when the green from the field is onscreen on a sideline-view camera with skin tones.
 

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Legend in his own mind...
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bluedogok said:
I noticed bad macroblocking on both the UCLA-USC and OU-Nebraska games, I switched to the antenna input on my TV and going to OTA did not fix a thing as it was there also just as bad. So in this area it was whatever signal that ABC was sending and not a D* issue.
I've recorded several things on my HR20 that I've been saving just so that I can take some pictures of the screen. I can easily pause the image and capture the screen tearing.

The common problem on my end is the MPEG4 delivery. Things on ESPN-HD and the other nationals look pretty good (except for when they knock down the bandwidth).
 

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Legend in his own mind...
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bonscott87 said:
Right. In *your* market DirecTV obviously hasn't upgraded the MPEG4 encoders yet. So yes, in your market and any others without the new encoder the MPEG4 HD locals are going to look like garbage compared to OTA. Known issue.

But in markets where they have switched to the new encoders and any new markets that have come online in the past couple months (which have the new encoders) the MPEG4 version is virtually the same as OTA to the point most people won't notice a difference.

But no matter what you do and no matter how good the encoder technology gets, nothing will ever be as good as pure OTA. Even cable has to encode the OTA signals sent to your cable box which decodes it. Hmmmm, just like satellite. Charter locally also compresses the HD locals to the point where again, OTA is superior.

It's just pretty much how the technology works. Once OTA gets activated on the HR20 I'll be using those instead of MPEG4 just because they are slightly better but I don't really have to.

So if your market hasn't had it's MPEG4 encoders upgraded yet I feel for you. It should get upgraded soon enough. If that's not soon enough for you then research other options that may be better for you.
When did I ever say anything about changing service? Maybe that was directed at others, dunno...

As for the encoder upgrades, where is this information published, which DMAs have older MPEG4 encoders and which have newer, and what the upgrade schedule is? I'd be interested to see it.

As for the "nothing will be as good as OTA" thats just not true. If I do a straight MPEG2 capture of the raw MPEG2 frames to a file or to a buffer and pass those frames through without re-encoding and attempting to change the bitrate (which is the ultimate goal of the re-encoding in most-cases) then yes I can get it just as good as OTA. But at the cost of bandwidth. Cable systems *could* pass the MPEG2 unchanged, but many times they don't.

The whole reason D* is going to MPEG4 is bandwidth. But the problem with D* and locals is how the locals are being delivered for backhaul. Right now, many times they're grabbing the local signal from an OTA antenna instead of uncompressed. If they were grabbing it uncompressed and then directly encoding it, it would look as good as MPEG4 can. It would cost D* a lot in local fiber, since HD-SDI runs up to 1485Mbits/sec (see http://www.opticomm.com/Video-HD-SDI___158 for details).

By taking an MPEG2 source and then re-encoding it to MPEG4, the quality suffers even more. You introduce all the artifacting and blocking from MPEG2 and just re-encode all those artifacts and blocks back into MPEG4. MPEG4 can't recreate all the lost data.

It's like taking a 64k mp3 and re-encoding it into OGG to try to make it sound better. It's not going to happen. If you take the original WAV file though, take that and compress directly to OGG, you are finally able to take full advantage of the improvements OGG offers over mp3.

Anyway, it'll be interesting to see how this shakes out.
 
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