Shattering the eyeglass: Using Kaitai Structs to dissect the eyeglass’ contents

by @beet_keeper

In my post from 2012: Genesis of a File Format, I created a new file format – the Eyeglass file format. The format provides a mechanism to persist information about a patient’s eye health following a checkup at an opticians. Today in 2023 we can use the format to understand how to make use of Kaitai Structs for understanding file formats.

Given the disclaimer that I am not actually an optician and that the format is purely illustrative, let’s look at the eyeglass again below.

#code #coding #digipres #digitalLiteracy #digitalPreservation #fileFormat #fileFormatAnalysis #fileFormats #kaitai #pronom #yyyy

Just realised something I though was tomorrow (23rd of the month) is actually next week. I think I misread dd/mm/yy (UK style) as yy/mm/dd (big endian).

For context, I like and use #ISO8601 style #yyyy-mm-dd dates, familiar to computer people as they sort chronologically, and people who've lived in Japan as they use that order.

I strongly dislike dates written with two digit years. You can probably guess, I hate the USA mm/dd/yy style with a passion.

Genesis of a File Format

by @beet_keeper

Working from the bottom up and ignoring formal preservation descriptions of a file format (see: File Format a rdfs:Class) – a file format represents a place to store information outside of a software application. It mirrors internal memory but promotes the use of the same data outside of, and in between applications.

Formats can be taken for granted. As a software developer I will have

#digitalPreservation #eyeglass #eygl #fileFormat #programming #python #yyyy