Encoded format?  QR-code in one of the higher versions (eg. version 40) would work great:

    http://www.qrcode.com/en/about/version.html
    https://en.wikipedia.org/wiki/QR_code#Storage

=========================================================================

On the encoding side, we would clearly use Javascript.

Javascript QR-code-generators that support version 40  (and other versions)

    https://github.com/soldair/node-qrcode
    https://github.com/janantala/angular-qr
    https://github.com/LazarSoft/jsqrcode
    https://sites.google.com/site/colinguiworks/home/qrcodejavascript

It can be accomplished using *only* client-side JS code.  Client-side scripts can actually read
files off of the local disk:

    https://en.wikipedia.org/wiki/HTML5_File_API
    https://scotch.io/tutorials/use-the-html5-file-api-to-work-with-files-locally-in-the-browser
    https://developer.mozilla.org/en-US/docs/Using_files_from_web_applications
    http://html5demos.com/file-api-simple

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On the decoding side, we'd probably use Python.

Libraries:  (though TODO, I need to find out which ones will decode version 40)
                https://pypi.python.org/pypi/zbar
                http://pyqrcode.sourceforge.net/
                https://launchpad.net/qr-tools










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Older notes...

        http://OpenCV.org/
        http://SimpleCV.org/
        http://luispedro.org/software/mahotas/
        http://luispedro.org/software/pymorph/
        http://ilastik.org/
        http://scikit-image.org/

Other info:

        http://ProgrammingComputerVision.com/

Example projects of decoding data from images, when the data is encoded in a similar way to our
project:

        in Python:
                https://pypi.python.org/pypi/zbar
                http://pyqrcode.sourceforge.net/
                https://launchpad.net/qr-tools

        QR codes:
                [description]  https://en.wikipedia.org/wiki/QR_code#Storage
                [description]  http://www.nacs.org/LinkClick.aspx?fileticket=D1FpVAvvJuo%3D&tabid=1426&mid=4802
                [algorithm]  http://www.swisseduc.ch/informatik/theoretische_informatik/qr_codes/docs/qr_standard.pdf  (chapter 3, "reference decode algo")
                [algorithm]  http://www.hindawi.com/journals/mpe/2013/848276/
                [algorithm]  http://ufodesign.ro/dm/A%20method%20for%20fast%20detection%20and%20decoding%20of%20specific%202d%20barcodes.pdf
                [algorithm]  https://pdfs.semanticscholar.org/618c/a6f4e2ee66cf7b7a05f3924a8c8dfd4fbd0d.pdf

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