So, you made a half hour film. At DV resolutions that takes up about 5 gigabytes of storage. How are you going to back it up?

Well, yes, you can print to tape. I do that too. Print to tape, keep the tape forever, yes, that’s a good idea and all but it seems so…low tech. Where’s the excitement? Where’s the danger?

Press to DVD, you say? Excellent idea — just write a DVD-R with the raw DV data, and — oh, wait. This file is bigger than we can fit on a single DVD. Well, that’s OK, we can use Stuffit or some other tool (live dangerously — use dd!) to split it into manageable chunks. Of course, if one of those DVDs suffers a media failure, you’re screwed. And writing multiple copies of multiple DVDs can be such a drag.

Here’s what I do, for when I’m feeling really paranoid:

Take your 5 gigabyte movie and split it into 100 or 200 megabyte chunks. Take the chunks and feed them into MacPAR deluxe or its Windows equivalent. Generate about 30 to 50 parity files; for each parity file you generate you’ll be able to tolerate a media error in one of your data files. At your leisure, write the data files and parity files to a few DVDs. Most of the media failures I’ve encountered on DVD-Rs tend to affect individual files rather than the whole disk, so I think it’s a reasonable strategy to just split the data and parity files over two discs. If and when you encounter media failures, you just use MacPAR to reconstruct the lost data from parity.

If you want to be super-paranoid, you can even sprinkle the parity files among any other DVD-Rs you’re writing at the time (I find that I always have some headroom when writing data DVDs).

Voilà! You have a redundant array of inexpensive DVD-Rs. You are now cyber. Congratulations!

 

Comments are closed.