peff/paperback

Create backups of arbitrary data to paper using qrencodes. Data is split
across several pages automatically.

Usage is something like:

# create a backup
gpg --export-secret-key | paperkey | paperback | lpr

# restore; you'll need to present the qr pages in order
zbarcam --raw | base64 -d | paperkey --pubring ... | gpg --import

Requires:

• qrencode
• imagemagick
• zbar
• psjoin (from psutils)

TODO:

• can probably fit more data per page; needs testing

• could possibly use 8bit QR encoding, but zbar does not seem to
  support it

• "part" title gets cut off by some printers; probably needs better
  margins

• title should be customizable