Subject: Re: OT: Video -- digital archiving

Bob Arnold rfarnold at bu.edu
Fri Aug 23 11:49:01 CDT 2002


Regarding Sivakatirswami's questions below:


> Message: 5
> Date: Thu, 22 Aug 2002 17:36:38 -1000
> Subject: Re: OT: Video -- digital archiving
> From: Sivakatirswami <katir at hindu.org>
> To: "use-revolution at lists.runrev.com" <use-revolution at lists.runrev.com>
> Reply-To: use-revolution at lists.runrev.com
> 
> 
> A) what media is used to store the uncompressed video if not tape? I have a
> sinking feeling that for the quantities of data we are looking at, were one
> to save 1000 hours of uncompressed video to a digital format, that removal
> media of any kind is simply not there yet. I guess one has only to try a few
> hours and then do the math....what do the "big boys" do?

As far as I know, best storage option presently is backed-up digital video
tape (digi-Beta). As you note, optical devices have insufficient capacity
and hard drive mechanisms will probably not last as long as the data on the
tape, assuming the tape is stored properly. Film, of course, is still a
preferable medium for long-term storage.
 
> B) how to read/view those files for cataloging... Can Quicktime "see" raw
> uncompressed video? I.e. Assuming assuming  QT can read it, Rev can also and
> then the issue is time to view on-line to some harddrive on a server over
> the LAN... 

As most uncompressed non-linear editing systems are QT based, it must be
able to, although specialized codecs may have to be supplied with the
capture card.

> C)  Troy mentions that DV might suffice for VHS tapes... We are quite
> ignorant here. One of my young team thinks that "uncompressed video" = DV
> format. But Troy says it is DV = 5 to 1.

DV is 4:1:1 which roughly translates to 5 to 1. Although a source of
argument, it is roughly equivalent to analog BetaSP, far superior to VHS,
but fine as a storage medium for VHS output -- note however that DV does NOT
re-compress well, so it is NOT ideal for DVD distribution or upsampling to
HD, and VHS may not have much of a future.

Any 4:2:2 (3:1) compression format, such as JVC's D-9 (formerly known as
Digital-S) and Panasonic's  DVCPRO50, are considerably better, and more
suitable to upsampling to HD and down to DVD.

Ideal, but much more expensive, is Ditial BetaCam (2:1).

For a lot of useful info about DV and other digital video formats, go to:
http://www.adamwilt.com/DV.html

> What then is the file format for "uncompressed video" if not DV?

D-5 (10-bit uncompressed component digital)
D-1 (8-bit uncompressed component digital)
D-2 and D-3 (uncompressed composite digital, much poorer quality, but if the
original video was composite (VHS or 3/4") no difference.)
 
> The goal is to avoid building an expensive environmentally controlled
> cabinet for the original tapes, and download them all as compressed MPEG's
> and view them in Rev. but then to go into production would require  going
> back to the physical tapes...what is the industry standard these days for
> saving and archiving? Physical tapes? Uncompressed Video on what media?

As far as I know, most archives (where long-term storage is the first goal)
use digi-Beta tapes, everything duplicated  and stored in temperature and
humidity controlled environments.

One, of course, should always store the original tapes, whatever format.


I hope this helps.
 
> Hinduism Today
> 
> Sivakatirswami
> Editor's Assistant/Production Manager
> katir at hindu.org 
> www.HinduismToday.com, www.HimalayanAcademy.com,
> www.Gurudeva.org, www.hindu.org
> 
> Read The Master Course Lesson of the Day at
> http://www.gurudeva.org/lesson.shtml
> 

-- 
Robert Arnold
Associate Professor of Film
Boston University
Tel (617) 353-7735  Fax (617) 353-1084
News: http://people.bu.edu/rfarnold/Announce.htm




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