HD1080i De-mystify HDTV 1080i ::: know why before you buy

Monday, September 18, 2006

HD-DVD and VC-1 / Mpeg2/4

... I got a slew of questions, mostly the MPEG4 crowd wondering why i'm talking about VC-1.

Ref MS PR from April : http://www.microsoft.com/presspass/press/2006/apr06/04-24HDDVDPR.mspx Note: NBC/Universal is correct in their assessments.
iTwire: http://www.itwire.com.au/content/view/5647/53/

OK so the President of universal claims; “The reviews are in and HD DVD is hands down the leader in picture quality, audio experiences and interactive capabilities that have never been seen before,” said Kornblau. Of course the "reviews" are in fact NBC/Universal people but the fact is, he is correct ... but you need to know why.

Truth?> do not credit the HD-DVD disc itself.
The great image quality is in the codec that can be used in HD-DVD, and that is VC-1.
VC-1 can be used in any DVD, it just so happens that HD-DVD is where you will find it right now.


VC-1 ( SMPTE 421M-2006) is better at HD 1080p and 720p, any framerate.. it seems to compress without incurring the issue of scene change block recovery (that blocky pixel clobbered crude look ) and stays clean on fast scene cuts and high action video preserving detail, when in my mind, it matters most.

MPEG4 and VC-1 will look the same in talking head news and basic things, but VC-1 is freshly minted code that cleans up the messthat the last generation of codecs forced us to live with. The result is cleaner playback for a smaller filesize, or conversely, more quality if the quality was there to begin with, it will be preserved with a more compact format.


the questions and very short answers....

Will this matter to you? Yes.. if you have an HD-DVD and you see a VC-1 format was used, it is going to look great period. Blu-ray uses mpeg2, which means its compression to get the same clean look will require more file space.

(CORRECTION [Nov-06] - Blu-ray does support VC-1, as of when i do not know, so basically the format exists via licenseable usage for publishers, regardless of media constraint, i think this is partly due to DRM transparency allowing it, and that is a good thing. )

In a word or 2 , those that think HD-DVD is not as good for movie releases simply because it has less of a storage capability are not aware that with VC-1 you get 2-10 times the compression for the same image as Mpeg2 and probably 2-4x MPEG4. So HD-DVD with VC-1 just doesnt need the old bloated codec or its space requirement since it can do a great job of delivery for a full length Movie in 1080p. In fact i can make a nice 720p HD in VC-1 at 5-6mbits for about 180 megs every 5 minutes of runtime. do the math- this means a 1hr 45 min HD 720p video in VC-1 encoding can fit on a regular old 4.5 gig DVD, and use windows media player in full screen mode to display it.

In my most humble opinion, the VC-1 codec can enable IPHDTV at 5 mbit bandwidth rates.
My FIOS fiber optic connection can just about handle that.

This is good. I can edit an HD video, upload it it for review in a couple minutes, and get client feedback quickly, and they can see detail on thier 1280 pixel computer screens with windows media player enough to guide the development. If they like it in 720p they will love it in 1080.

Is that Macroblock thing in VC-1?
Macroblocks that are visible represent a failure in image rendering due to data rate or error correction... VC-1 is not the same, it has other points of failure in error correcting, and in my opinion its block recovery is a more elegant solution. Be wary though, a transport stream and a basic file codec are in fact a bit different ( bad pun ) It will pixellate and get blocky when the author of the video over-compresses to a point well below the bit-rate needed, but if you follow guidelines, you will not often see any issues. Macroblocks are an MPEG-specific definition.

OK - HD-DVD - Blu-ray and whatever...

What is all this Multiformat stuff?
Some companies are making a possible play into a player/disc option that covers all bases.
Basically the usage fees for content publishers to employ Blu-ray causes one set of standards and DRM to happen, HD-DVD causes yet another etc ... To prevent fence-sitter behavior in the consumer-space, i expect multiformat systems to appear... however if they too get greedy about patents and trademarks, then it will still be a case of proprietary supply-side control that will break standards down to a lowest common level of mundane, in the quest for ubiquity. I am not sure i want a bi-polar DVD player, i need to give it some thought.

Other questions:
Can 1080i run a computer resolution of 1080 vertical pixels?
Yes - it is what i do infact - get an Nvidia 7600 GT or better video card and just plug that DVI into whatever 1080 HDTV you have, mine is a Westy LVM-37w3 costs 1400 bucks at best buy and it rocks for an LCD. Most all 1080 HD monitors will also run 1920x1080 in VGA mode too.
I would ASK the store guru first though, some monitors require your system to have a driver to use VGA properly for thier display at that resolution.

Addendum: It took me a while to finally make a decent longform HD piece... so i encoded it in WMV-HD 1080 and found this out... basically for a lot of stable-scene situations like interviews and talking head stuff , i got about 22 minutes per gigabyte 1080p pristine, Stereo Audio. [Begin: rant] THE VC-1 CODEC. Oh my... do the math. A regular DVD can hold a decent 1hr HD tv show with room to spare. I had one segment 300 seconds (5 minutes ) runtime in 200 megs, lots of high action scene cuts in that part. Damn. If someone just made an HDMI/component output 1080p DVD player for WMV-HD ... but oh wait.. you can buy a nice tiny AOPEN computer with 1080p DVI output, the Windows Media player 11 is free, for about 500 bucks. copy the DVD file to the hard drive and play it. Take that a step further, get the Logitech Remote. badda-boom badda-bing... its done. You can probably download a VC-1 60 minute tv show in just over 3 gigs, and love every frame, even the advertizing in it. Ok do not get me wrong, I still want to make BD 1080 and in 2007 i will ship a Ps3 with my HD product to the clients that want HD in a box for thier videos, but really, I am impressed with VC-1 to the point that i may just use it for Archive and b-roll storage for HD in my system, get my on-line terabytes back for the next editing job. Broadcasters should be using VC-1. I am so sick of Mpeg Macroblocks. I Know the VC-1 people are aware of how compact this Codec is, but i wonder if the rest of the world does? Is it shunned for being a Microsoft thing? If you know what you are doing, and take the time to do it well, VC-1 absolutely cannot be beat. [End:rant]

I need to maybe come clean on something, i am not just a HD1080 / HD fanboy. I create HD video , shoot and edit the stuff, so my view on it is a bit more intense than most will have. Something that can and will affect what you see is called a CODEC, and it is the method by which your Video is stored as a file on DVDs. It is the COmpress-DECompress process that is used in creating , storing and playback. It is more than simply a format like Quicktime or AVI and a lot of fancy software and firmware code is needed. It is a huge enabler, like Mp3 is for music files. So MPEG 2 , MPEG4, VC-1 are all really code-driven ways of getting digital video to you, most digital cable is MPEG.


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