Re: DVD

Oksana Dykyj (oksana@vax2.concordia.ca)
Wed, 13 May 1998 09:40:48 +0000 (HELP)

>Chris Lewis writes:
>I'm zo confuzed. I'm probably missing something in this discussion
>regarding frame-by-frame analysis but here goes anyway... I understand
>the value of freezeframes and frame-by-frame analysis in the course of
>film study but LDs are playing at 30fps the same as DVDs, correct? It
>sounds like you are suggesting that an LD is able to deliver video at
>the same fps rate (24) as film. I always thought the frame-count on a
>laserdisc was based on the number of actual video frames at 30fps.

You're absolutely correct but the only way to replicate actual frames from
film to video is in the CAV format (Constant Angular Velocity). Each of the
24 film frames per second of sound film is accounted for in the analog
transfer to disc. The same could be done for 35mm still photography hence
the availability of art laserdiscs with a possibility of 52,000 images per
side. This is why there is only 30 minutes of screen time per side of CAV
disc as opposed to 60 minutes per side of CLV disc. CLV discs are straight
analog video transfers (no compression at 30 video frames/second).

>Besides I challenge anyone to prove to me that any director of
>live-action film actually choreographed his/her film down to the
>individual frame (though some, perhaps Stan Brakhage, may claim to after
>the fact). Of course editors cut to the frame but what they are really
>cutting on is a moment of an image which is preserved in each of the
>formats.
Many individuals studying experimental film, animation, and theoretical
approaches to live action such as the montage theories posited by Sergei
Eisenstein, count actual frames to see how tension is built and to even
calculate algorithms on the best way to decrease or increase shot length.
I'm always surprised at what research is being done. (Apart from Brakhage, I
would offer Bruce Conner, Robert Frank, Eisenstein of course, and numerous
others whose construction of their art work was often performed one frame at
time).

Oksana
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Oksana Dykyj
Head, Visual Media Resources
Instructional & Information Technology Service H-342
Concordia University
1455 de Maisonneuve West Tel: 514-848-3443
Montreal, QC, H3G 1M8 Fax: 514-848-3441
CANADA Email:oksana@vax2.concordia.ca
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