The BACKFIRE Project


Welcome to BackFire.

This is a hastily thrown together web page to serve as an accumulation point for specs, data, code, etc. for the project. Backfire is the working name for a package to allow the backup (and restore!) of data files to a DV-format (Digital Video) camcorder device via an IEEE 1394 link (aka FireWire or i.Link).

Why?

The rationale is as follows: a lot of folks (eg, me) have DV-capable video camcorders, either mini-DV or Digital-8 (which records DV data on an 8mm tape). These cameras are designed to transfer digital video data to and from computers via a high-speed link. An hour of DV (Digital Video) data (one tape's worth) is about 12 gigabytes, (less than that of real data when you exclude format overhead). This makes it an ideal backup medium for the larger size harddrives that are becoming available, at a quite reasonable price (about $800 for a low-end mini-DV or D8 camcorder, and another $80-$100 for a IEEE 1394/FireWire/i.Link card and cable) compared to the multi-thousand-dollar commercial DAT/8mm/whatever based SCSI tape backup systems that are currently the only feasible option. (The low-priced consumer tape drives are too horrendously slow to make regular backup of a 20 or 30 GB drive practical.)

What?

The core of the package will be a program that takes a regular data file (a tar file, for example) and encapsulates it in the video frames of a DV stream. (As far as the camcorder is concerned, it'd look like a video of static, probably. The audio track is left clean to avoid any potential damage to speaker systems, etc, if the tape is inadvertently played back in an AV system.) Similarly it would strip the DV framing off such a stream to restore it. (Appropriate interfaces for doing an actual backup or restore of a file system would then be layered on top of this core.)

The intention is to release code under the GNU General Public License and develop on and for the Linux OS (and any similar Unix OS using the same 1394 API).

Who?

I'm Alastair JW Mayer, long-time programmer, part time hacker. See my personal home page for more bio.

Several other folks have expressed interest and may be contributing, I'll update this as appropriate.


Project Status Page

Follow the above link for a progress log on the project (not much, at the moment).


Some Links

At the moment (10 April 2000) this project is in the data gathering stage, here are some links found so far to relevant information/other projects/etc.

DV Coding: How it Works with IEEE-1394 - from a slide presentation on how DV data is encoded for 1394.

dvgrab - DV Video with Linux - Arne Schirmacher's program to grab DV video into AVI files (some of his code may be useful for 'backfire').

The Linux 1394 project - homepage on SourceForge, for more generic Linux IEEE 1394 stuff.

..more to come..

Meanwhile, any questions/comments/etc can be directed to backfire@ajwm.net.


(Note: FireWire is a trademark of Apple Computer and i.Link is a trademark of Sony for their IEEE 1394 products. Neither company is associated with this page.)
This page last updated 11 April 2000.