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1. It is not true HDTV, but a half-way house.
2. It will become a de facto standard with no official approval from the CCIR, which is the standardising body for TV and has been developing its own HDTV standards.
3. MPEG-2 is a standard and if this body starts to muck around, altering it to facilitate editing, it will make a maverick version with obvious compatibility problems.
4. MPEG-2 does not lend itself well to editing, with re-rendering, causing definition losses, required.
5. MPEG-2 is unlikely to remain a definitive standard. Discussions are already well under way to replace it for satellite, cable and DVD recording. An article in the latest IEE Communications Journal indicates agreement on this is likely to be made this year. Yes, it will mean that set-top devices will need to be changed within a few years and dual standard ones will appear next year.
6. I'm not happy that straight mini-DV tape is the answer. If it is "slowed down", then the compression must be high and will therefore produce well-known MPEG-2-style artifacts galore, if the resolution must be maintained. I'm also not happy that an existing format is used for a totally different standard; it's bad enough differentiating mini-DV and DVCAM tapes which are essentially the same except for track width and tape speed: we'll get a rash of remarks, "I have this tape and it won't play".
IMHO, this is another commercial ploy to fool users into buying into something new, very much à la Sony, but it won't last the length. There are too many compromises.
Beg to differ. MPEG-2 does lend itself to editing IF the correct profile and level are used.
The profile we're most used to is MP/ML (main profile/main level) and is used for VCD, SVCD and DVD. MP/ML uses a reduced 4:2:0 colorspace and bitrates of up to 10 Mbps. It's a distribution profile and definitely not good for editing.
On the other hand the MPEG-2 Studio Profile/ML (aka: 422Profile/ML as is available in TMPGEnc) uses a 4:2:2 colorspace and can use data rates of up to 50 Mbps, but even at lower data rates it looks a lot better than MP/ML. The Studio Profile can be edited VERY nicely and didn't get the "Studio" moniker by accident.
Then there are the High Profiles and Levels.....
New profiles can be added to the spec, especially if there's a good reason. This may be one and with that much muscle behind it I wouldn't be suprised if it happened.
As noted in the article the JVC GR-HD1 already uses what is expected to be the new standard. This CamcorderInfo review of it has links to some frame grabs, the quality of which I find impressive;
Contact with an owner of camcorderinfo.com domain name.
Look for the links running 1 2 3 4 5 6
Basic MPEG comparison;
DVD MPEG-2:
15 frame GOP - IBBPBBPBBPBBPBB
up to 9.6 Mbit/s
VBR or CBR
GR-HD1:
6 frame GOP - IBBPBB
either 18.6 or 19.7 Mbit/s
CBR only
These bitrates are just short of DV's 25 Mbit/s.
Pre-recorded D-VHS-HD D-Theater tapes have a bitrate of 28.2 Mbit/s.
The use of a short GOP gives 5 I-frames/second instead of DVD's 2 I-frames/second, which bumps up quality and editability.
The bitrate is also almost twice as high as what is used in DVD, and from the practical standpoint 4x as high as what most of us are using to burn 120 minutes to DVD-R, but this will only be for editing.
Is it just something wrong with my downloads/bitmap viewer or is the right hand side of these frames from a different image? Especially jvc_hd6 & jvc_hd7.
I see some junk on the right border too, but it's likely junk in their viewers buffer left over from previous images. I've seen that at times with certain viewers and had to crop it off.
Dr. Mordrid
Dr. Mordrid ---------------------------- An elephant is a mouse built to government specifications.
I carry a gun because I can't throw a rock 1,250 fps
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