Contributing back to the commons in digital preservation hasn’t been for everyone.
We know the famous XKCD that touches on the underappreciated work of maintainers in obscurity. When you, or your institutions, or services are using free and open source software, or other information and data in the commons, and you’re not contributing back, you’re perpetuating this, and what’s more, there’s a virtuous cycle that we’re missing out on.
I read something the other day and it felt like a red flag.
I introduced bsdiff in a blog in 2014. bsdiff compares the differences between two files, e.g. broken_file_a and corrected_file_b and creates a patch that can be applied to broken_file_a to generate a byte-for-byte match for corrected_file_b.
On the face of it, in an archive, we probably only care about corrected_file_2 and so why would we care about a technology that patches a broken file?
In all of the use-cases we can imagine the primary reasons are cost savings and removing redundancy in file storage or transmission of digital information. In one very special case we can record the difference between broken_file_a and corrected_file_b and give users a totally objective method of recreating corrected_file_b from broken_file_a providing 100% verifiable proof of the migration pathway taken between the two files.
File Formats As Emoji (0xFFAE or 0xffae) might be my most random file format hack yet. Indeed, it is a random page generator! But it generates random pages of file formats represented as Emoji.
The idea came in 2016 with radare releasing a new version that supported an emoji hexdump. I wondered whether I could do something fun combining file formats and the radare output to create a web-page.
Along came a spare moment one weekend, some pyscript, and bit of sqlite, et voilà. File Formats as Emoji (0xFFAE) was made a reality.
In December I asked “What will you bitflip today?” Not long after, Johan’s (@bitsgalore) Digtial Dark Age Crew released its long lost hidden single Y2K — well, I couldn’t resist corrupting it.
Fixity is an interesting property enabled by digital technologies. Checksums allow us to demonstrate mathematically that a file has not been changed. An often cited definition of fixity is:
Fixity, in the preservation sense, means the assurance that a digital file has remained unchanged, i.e. fixed — Bailey (2014)
It’s very much linked to the concept of integrity. A UNESCO definition of which:
The state of being whole, uncorrupted and free of unauthorized and undocumented changes.
Integrity is massively important at this time in history. It gives us the guarantees we need that digital objects we work with aren’t harboring their own sinister secrets in the form of malware and other potentially damaging payloads.
These values are contingent on bit-level preservation, the field of digital preservation largely assumes this; that we will be able to look after our content without losing information. As feasible as this may be these days, what happens if we lose some information? Where does authenticity come into play?
Through corrupting Y2K, I took time to reflect on integrity versus authenticity, as well as create some interesting glitched outputs. I also uncovered what may be the first audio that reveals what the Millennium Bug itself may have sounded like! Keen to hear it? Read on to find out more.
Today I want to showcase a Wikidata proof of concept that I developed as part of my work integrating Siegfried and Wikidata.
That work is wikiprov a utility to augment Wikidata results in JSON with the Wikidata revision history.
For siegfried it means that we can showcase the source of the results being returned by an identification without having to go directly back to Wikidata, this might mean more exposure for individuals contributing to Wikidata. We also provide access to a standard permalink where records contributing to a format identification are fixed at their last edit. Because Wikidata is more mutable than a resource like PRONOM this gives us the best chance of understanding differences in results if we are comparing siegfried+Wikidata results side-by-side.
I am interested to hear your thoughts on the results of the work. Lets go into more detail below.
I want to let you into a secret: I enjoy corruption. Corrupting digital objects leads to undefined behavior (C++’s definition is fun). And flipping bits in objects can tell us something both about the fragility, and robustness of our digital files and the applications that work with them.
I had a pull-request for bitflip accepted the other day. Bitflip is by Antoine Grondin and is a simple utility for flipping bits in digital files. I wrote in my COPTR entry for it that it reminds me of shotGun by Manfred Thaller. The utility is exceptionally easy to use (and of course update and maintain written in Golang) and has some nice features for flipping individual bits or a uniform percentage of bits across a digital file.
My pull-request was a simple one updating Goreleaser and its GitHub workflow to provide binaries for Windows and FreeBSD. I only needed to use Windows for a short amount of time thankfully, but it’s an environment I believe is prevalent for a lot of digital preservationists in corporate IT environments.
Bitflip is a useful utility to improve your testing of digital preservation systems, or simply for outreach, but let’s have a quick look at it in action.
It is very poetic to think about code as it containing the memory of its maintainers. I don’t entirely disagree with the idea, but it’s overly poetic and the reality of maintenance on systems that have become too unwieldy is anything but poetic.
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.
