RE: [AV Media Matters] Video Compression - a PLUS for archivists

[Jim Wheeler <Jimwheeler@aol.com>]

I have posted this before but it seems that it must be repeated every few
months.  Many people do not understand that there are two archival
communities.  One is the present Broadcast community that must deal with
material thay originates on a compressed format.  For most archivists, the
issue is how to take care of the hundreds of millions of hours of video on
deteriorating media.

                                   ARCHIVAL VIDEO STATUS
                                                 Jim Wheeler

There is no ideal medium for long-term storage of video.   The present
situation for an archival medium is as follows:

1  Digital videotape formats introduced in recent years are compressed AND
use very thin basefilms.
2  The compression methods being used degrade the quality of the video.
3  The standard video DVDs use compression
4  D5 and D6 are uncompressed digital videotape formats but the machines are
very expensive (about $80,000 US).
5  Some new formats, like Ecrix, store an incredibly large amount of data in
a small cassette but use very thin tape.
6  E-Cinema is using QuVis with only 5 or 6 DVDs for a feature movie.  The
QuVis system uses a QuBit box which uses Wavelet compression to compress the
video.

At the AMIA Conference in Montreal, Reinhard Knor of IRT gave a
presentation about COMPRESSED videotape formats.  In summary, the
IRT tests show that if you stay with only one type of compression
technique, you can migrate many, many times, but mixing formats with
different compression techniques degrades the video quality.  If you
want a copy of Reinhard's presentation, contact me and I will send
you a copy.  It is about 600K in PDF (Acrobat).

The IRT tests are most beneficial to those who are in the Broadcast
TV business but most video archives still have the problem of what
to do with their analog collections that are on deteriorating media.

The May 1999 issue of "Digital Video" summarized the results of
extensive testing of videotape formats for degradation of video
quality when making copies.  The results were that ALL of the
videotape formats that use compression degrade the video quality. If
you have Acrobat, you can download the report from the Digital Video
magazine website: www.dv.com/magazine/1999/0599/formats0599.pdf

The wavelet compression being used by QuVis has little effect on
video quality at compression ratios below about 15:1.  To verify
this, we need a lab that will test it.  For information about QuVis,
go to their website: http://www.quvis.com