Papiro is a script that encodes and decodes files to/from QR Code(s).
You can encode a single file or a full directory, in the latter case the data are zipped before the encoding.
The QR Codes are saved in a single pdf, ready to print; the rebuild process is done on a group of QR Codes' photos. Papiro is useful to save files in a non digital fashion for backup and portability pourposes using a printer. You can encode passwords, secrets, credentials, 2FA backup codes, crypto seeds (mind the privacy!) and any text/binary file.
Papiro is the italian word for "papyrus" 📃
Because paper seems the most resilient storage medium on earth, at least for low volume data, and QR Codes have an interesting error-checking system. So it is a nice backup solution to pair with digital ones.
Papiro uses the QR Code v40 (177x177 matrix) with low (default, you can change it with the -l option) error correction level; according to the specs with this config we can save 2953 bytes in binary mode on a single QR Code. An A4 sheet can accomodate 12 QR Codes for an unbelievable total of ~34.60KB! So a standard 500 sheets pack easily stores ~16.89MB, or ~33.79MB with an double side print. With the best (high) error correction level you can print ~14.91KB/sheet.
Papiro needs these binaries:
convertqrencodezbarimgmontage
Install the required binaries using brew:
brew install imagemagick
brew install qrencode
brew install zbar
Install the required binaries using your favorite package manager, e.g.:
pacman -S imagemagick
pacman -S qrencode
pacman -S zbar
If you get an error on Linux about the "convert: attempt to perform an operation not allowed by the security policy <gs|pdf>" add the following to /etc/ImageMagick-7/policy.xml:
<policy domain="coder" rights="read | write" pattern="PDF" />
<policy domain="coder" rights="read | write" pattern="gs" />
Clone the repo and make the script executable:
git clone https://github.com/dtonon/papiro.git
cd papiro
chmod +x papiro.sh
./papiro.sh -h
You can even download/copy the single papiro.sh file and make it executable, that's all!
# Encode a file to QR Codes in single pdf
./papiro.sh -c memo.txt
# Zip and encode a file
./papiro.sh -c divina-commedia.txt -z
# Encode a file with the best error correction
./papiro.sh -c important-data.xml -lH
# Encode a directory to qrcodes (using a zip file)
./papiro.sh -c mydata/
# Interactively create a new vim encrypted file and then process it
./papiro.sh -x
# Encode a file to QR Codes keeping the filename secret
./papiro.sh -c cat.jpg -a
# Decode a group of images to rebuild a file
# Note: files have to be correctly ordered by name,
# cameras create sequential pics with a correct filename
./papiro.sh -r photos/ -o data.json
Papiro options:
-z Zip the file(s)
-l Set the QR Code error correction level (L|M|Q|H); default is L(ow)
-o Set the output filename
-a Anonymous mode, don't annotate the original filename
-s Create a papiro of the script itself, useful for archiving along with the encoded data
-h Show the help
-d Debug mode, create a debug/ dir with the temp images
You can create a papiro of papiro.sh itself using the -s flag:
./papiro -s
This command encode the script in QR codes with a brief description about how to decode and use it; it is useful to include with the encoded data, to ensure a easy way to decode it even if your don't have the original Papiro script and are using an air gapped system.
In the examples/ dir you can find a nice 60KB cat's photo and the 2 pages QR Codes-pdf-papiro generated with the following command:
./papiro.sh -c cat.jpg
This is a preview of the generated pdf (top cropped A4 page):
Or you can enjoy the full Divina Commedia in 7 pages or Moby-Dick in 15 pages, too!
Remember that a QR Code slightly obfuscates your data but it does not protect them in any way; if your data need privacy you have to encrypt them before using Papiro. This is also useful to avoid the printer's attack surface. To apply a good privacy layer you can use GPG, a password protected zip (also useful to reduce the file size and so the number of QR Codes) or the built-in "new vim encrypted file":
./papiro.sh -x
You can also use the -a option to don't annotate the filename on the created pdf.