Doesn't AVCHD have a much more efficient compression rate, as it isn't lineal? I thought you could reduce Mbs by 1/2 to 2/3 with comparable results to MPEG2. If memory serves the highest on AVCHD is about 9 to 17Mbs on a consumer 1920/1080i video camera and Sat/telephone efficiency was at least as good, but probably better.this is from uverseusers.com site
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Ok, ran a few things and still crunching it all in my head. But I've become a sort of videophile lately and have run a few things concerning HD quality.
First off U-Verse, from what I've been told, runs H.264 (AVC) for it's compression standard. I pulled a few bitrates from BD-ROM info I had culled from the net to draw a comparison.
The top overall quality encoded movies in BD-ROM using AVC are:
X-Men: The Last Stand - 27.5 Mb/s
The League of Extraordinary Gentlemen - 23.4 Mb/s
The Descent - 28.9 Mb/s
Eight Below - 23.3 Mb/s
These are all encoded in 1080p True HD with PCM 5.1 or DTS-HD. They are considered near flawless in terms of quality.
I finally found a decent argument for the bitrate differences. 720p uncompressed HD clocks in at roughly 1.3Gb/s while 1080p is roughly 2.98Gb/s.
Assuming a fairly even ratio across the compression you're left with roughly 44% the size.
That leaves a 720p image in high quality HD with those films listed above in a range of 10.2 to 12.7 Mb/s. If you want to go with 1080i the bitrate is half of 1080p so you're left with 11.6 to 14.4Mb/s.
Currently AT&T, I believe, encodes their video in HD to be under 10Mb/s
From what I gather if they switched to VC-1 they'd have reference level picture quality. As is they're pretty darn high still. And since VC-1 is Microsoft's codec and MS is making AT&T's IPTV software, well, here's to hope.
I can't get the service yet so I have no clue how the real world application of picture quality is but it gives me hope that it'll be as good as I hope.
Feel free to discuss and point out holes, I look forward to it.