archiving & compression

[Samantha Disbray]

> Hallo info childes

thanks to everyone taking part in this discussion, very relevant to the
project we are working on- Aboriginal Child language Acquisition Project
(ACLA- Universities of Melbourne and Sydney, Australia). We are video
recording 24 children in 3 field locations, at 6 mnthly intervals, over a
3 year project, looking at caregiver input. With the final field trip
approaching we have some 300+   hours (6000GB) of video data, with
different media stored in different locations.

DV tapes currently with the researchers,  to be deposited at an archive in
the capital, Canberra.
These seem to offer a backup in the short\medium term, which the new
generation DV cameras with internal hard drives don't offer. Ofcourse the
mini DV cameras will be quickly superceded and less available.

We also invested in Lacie big disks (500GB). These have not been 100%
reliable with the first 4 all requiring repair to the fire wire port
socket as thhey continuously failed to mount. This appears rectified. One
of the drives now has a mechanical fault and it is not certain that the
data can be retrieved- perhaps reason not to upgrade to the new range of
1000GB drives- a lot of data to loose.

We also have access to a data storage facility in Canberra, with a high
speed connection between it and the universities. Still up and downloading
is slow.

As for formats, we have been keeping full quality QT files and also making
QT compressed versions, small enough to store a number of a laptop,
allowing field workers to work on transcripts with participants, without
lugging external hard drives, requiring power etc.
The settings we have used are (File - Export Movie to Quicktime movie-
Options) under settings - frame rate 15, size 360 x 288. These reduce 18
GB (40 mins) to 1GB. The screen size is small, but quite clear enough,
sound quality is unchanged.

I am wondering if anyone can recommend some standard compression setting
to store QT movies (of around 1 hour in length), which i DVD accepts, and
which fit on a Dv disk.

Samantha Disbray




>> I'd certainly also advocate archiving valuable material in 2 different
>> formats, stored in 2 different places. Our 'standard' system for video
>> is to keep original material on DVC tape, with a copy in AVI format on a
>> USB hard drive. Yes AVI files are huge, but they're easy to make and
>> edit, and are guaranteed to replay on virtually any computer. Their size
>> isn't really a problem these days - 250GB USB drives are getting common.
>
> ... and the two different places should be geographically separated.
>
> Off-hand, I can think of recent examples where universities sustained
> major damage
> (ranging from a whole building to multiple buildings) from fire,
> hurricane, flood,
> and PETA sabotage.   I also know of an example where undergraduate
> research
> projects were sabotaged.   That was especially hard to recover from,
> because the
> backup tapes were stored in the same room and were removed at the same
> time as
> the disks.
>
> I also know that even reputable academic departments and companies often
> keep backup tapes in the same or a nearby building, which is ok for minor
> machine meltdowns but not for disaster recovery.
>
> Send a second copy of your data to a colleague or relative far, far away.
>
>
> Margaret
>
>
>
>