#wdpd2024 — Public Fediverse posts

Perhaps you've heard about the launch of the new #DigitalPreservation for Community Archives Toolkit on #WDPD2024?

We're hosting a 🎉 special #DPClinic 🎉around the toolkit on Monday, Dec 16, 5-6pm UTC, to tell you more about its use by and for community archives working with digital content.

All are welcome, DPC members and non-members alike. We hope to see you there!

Register (for free) at https://www.dpconline.org/events/eventdetail/412/-/dpclinic-december-community-archives-toolkit

PRONOM’s dustiest records

NB. because of the complexity of this post, it may be easier to read in original blog form, than on Mastodon here: https://exponentialdecay.co.uk/blog/pronoms-dustiest-records/

Tyler’s recent blog post for the PRONOM Hack-a-thon Week 2024 (my previous for this week), brought up an interesting point about two of PRONOM’s oldest outline records, Real Video Clip (fmt/204) and Real Video (x-fmt/277). How did they end up in PRONOM?

Tyler suggests:

I assume PRONOM originally added these based on MIME types available.

I thought I knew the answer, and so it prompted a forensic look at the records to see if what I thought I knew aligned with reality!

As a PRONOM maintainer at The National Archives, UK from 2009-2012 I knew a little bit of the history of the system, we see some of that history impact us today, for example, when we look at the number of records that don’t have descriptions or file format signatures, 156 of those records are so-called x-PUIDs. A mechanism in PRONOM that was never meant to make it into the wild for working on file formats internally without polluting the public record. There are 455 x-PUIDs in total. They made it into the wild anyway (before my time) and so they exist as a symbol of PRONOM’s dustiest oldest records.

Even by the time I had started, PRONOM still had a lot of what we started to call outline records. One of the more positive changes we made to the process back in the day was that we would stop creating outline records; instead, we would focus on records that could be tied to signatures. This didn’t necessarily make the records more correctly aligned with reality, but it meant records had utility and file formats identified by DROID could be tied back to something that PRONOM “knew about”. I believe the process is a bit more flexible these days, allowing individuals to contribute information to records that tie them back to information like MIMEtypes and specifications. It’s clearer the format is “real” even if a signature is yet to be developed (and of course there are a large number of data formats that are hard to even represent in traditional PRONOM signatures any more and so they need a record, even if there isn’t a neat concept of a signature for them).

Okay old-man, but what about Tyler’s thesis?

Stellent and PRONOM

I learned sometime in my tenure at The National Archives that PRONOM had been seeded with a lot of the formats listed in a technology called OutsideIn previously owned by Stellent and now owned by Oracle.

I had always had a feeling that that the scope of this list was largely exaggerated by the company selling the software as it is a marketing tool; and if not exaggerated, perhaps, just not as clearly delineated by format than PRONOM, and rather, by Software, regardless of the properties of a given “format”, e.g. WinZip, and PKZip.

Back to the story though, I was also reasonably sure I would find Tyler’s RealVideo formats in the format listing but, I did not!

I downloaded a CSV summarizing the PRONOM records from api.pronom.ffdev.info with:

curl -X 'GET' \
 'https://api.pronom.ffdev.info/pronom_summary_csv' \
 -H 'accept: application/csv'

I filtered on outline entries and those without signatures only. I went through the entries still remaining and looked for name matches. I did find some name-for-name matches and some that were close, but no RealVideo or RealVideo Clip.

The matches:

The maybes:

11 exact matches! It’s hardly a headline!

I had hoped that if I found more exact matches it would provide some clues to where some of the older PRONOM entries came from. I expected most of the outline records to come from this list, alas, it isn’t nearly as many as anticipated.

I hoped too that going through the list I might get more clues as to formats that could potentially be deprecated in PRONOM.

As it stands, from the OutsideIn list, the only records I would personally recommend for deprecation are:

7-bit ANSI Text7-bit ASCII Text8-bit ANSI Text8-bit ASCII TextEBCDIC-USUnicode Text File

We know enough now to be almost certain that if something that looks like these files arrives in the archive it will present as a standard text file, and that we will need to rely on determining the character encoding using tools such as Richard Lehane’s characterize (see characterize’s README for more background). It is unlikely we will be able to attach a signature to these records, and we know there are a great deal more encodings in the world than need be represented as PRONOM identifiers.

NB. this might be something to formalize in a PRONOM decision making rubric, connected also, to formalizing approaches for XML based signatures.

A bit of a let down, or is it?

Still uncomfortable with so many outline records and little provenance for them, I wanted to find more information about the source of PRONOM data and so I decided to take a different path — I surfed the internet for answers!

Out of the list of outline records I found a few to be overly specific, or slightly weird, i.e. not really things we hear much about day-to-day, some examples:

ACBM graphics? Dr Halo Bitmap? Btrieve database, “5.1”? where are the other five?!!

It gave me pause. I didn’t believe these were all formats well-known to folks who created PRONOM, and I know we didn’t have such an advanced digital transfer program at the time that meant agencies were submitting huge variations of formats to PRONOM for future preservation.

I felt they had to come from somewhere, but where?

Enter Filext.com

Because these formats were very specific I found listings on the internet that I knew had to be part of the story. I had immediate luck just looking for combinations of these names, e.g. ACBM Graphics + NAP Metafile.

In particular I found listings on different websites from hobbyists or universities that all looked the same or similar, e.g.

• https://www.oocities.org/iannaccif/extention.htm
• https://tecfa.unige.ch/guides/fileextensions.htm

There were definite matches with PRONOM which we will get to, but I started to wonder about the provenance of these extensions.

I kept looking and I found one clue, a header and footer of a file that looked like those above and read as follows:

Copyright © 2002 Computer KnowledgeAll Rights ReservedThis download for personal use only. Do NOT distributeit to others either alone or incorporated into anysoftware without prior permission from Computer Knowledge.Developers who wish to incorporate portions of the listplease see the comments at the end of this file.

Developer permissions....This total file may not be included in any other software orproject which presents the data to the public or portions ofthe public. Any developer who wishes to include up to (butnot more than) 2,000 individual entries from this file is freeto do so provided certain conditions are met. These are:.  1) Credit must be given to FILExt. If links are available  in the developed product then one must also be provided to  FILExt as http://filext.com..  Suggested text: "File extension list courtesy of FILExt.  For a more extensive list visit http://filext.com.".  2) Once the extensions are chosen for one product by any  developer then these same extensions must continue to be  used by that developer for any other projects (i.e., you  cannot take one set of 2,000 for one project and a different  set of 2,000 for another project; it's a total of 2,000)..  3) If links are available in the developed product then any  links appearing associated with any of the 2,000 picked  extensions must be included in the product. (This covers  future plans to include such links in this list.).When the project is complete please notify FILExt with thespecifics at [email protected]. We're always interestedin how the list is being used. Thank you.

Filext.com!

And so I asked myself, how long had filext been around?

As it turns out, quite a while! It was forked from a site called cknow around 2002. cknow.com was registered around 1996 and filext.com registered in 2001.

The first appearance of cknow in the internet archive is late 1996: https://web.archive.org/web/19961219035827/http://www.cknow.com/ and Filext early 2001: https://web.archive.org/web/20010522235126/http://www.filext.com/

The sites were founded by Tom Simondi. It looks like he has been responsible for a lot of the 90s and 00s work around demystifying extensions and getting more information to folk about what to do with them.

Could it be the source of the first PRONOM records?

Comparing some of the many other text-based lists I had found with cknow and filext gave me some confidence that there was some shared heritage with the them, and so I asked, could the cknow and filext lists have also seeded PRONOM?

I picked a list close to 2002 (cknow Extensions: 2000) when PRONOM was first started and began to compare entries for exact matches.

46 matches!

17 maybes!

What did we answer?

Okay, 46 exact matches does not the full listing make (although many (now) full-entries may still have been made from these early listings). Filext may have been an important resource for the first PRONOM records, but it’s also likely that PRONOM had other sources of information. For example, for a number of the Microsoft formats with outline records read like export or save-as listings in previous versions of Microsoft software. E.g. Excel:

NB. I wasn’t actively researching this side of things writing this blog, but I can already see some commonalities, especially Unicode Text!

I know we also had a copy of the Dr Dobb’s Essential Books on File Formats CD-ROM in the archive, and so that may also have been an important resource when PRONOM was creating its first records.

I count only two overlaps with the Stellent list, Framework Database III and Nota Bene Text File.

We did, however, find the RealVideo Clip! And I think we found some decent correlation with a resource that looks likely to have been used partially to populate the PRONOM database.

The era of file extensions

• Throughout my research, I found a lot of similar websites. Filext seems to go furthest back and has the greater pedigree, but in the noughties a lot of other sites seemed to appear to try and provide similar information to internet users, a few of note that seemed comprehensive and particularly well presented:

• Endungen.de (Internet Archive circa. 2002) https://web.archive.org/web/20020603193356/http://www.endungen.de/index.php?changelanguage=049
• Dotwhat.net (Internet Archive circa. 2005): https://web.archive.org/web/20050615021635/http://www.dotwhat.net/
• File-extension.net (Internet Archive circa. 2007): https://web.archive.org/web/20070521093707/https://file-extension.net/
• Filesuffix.com (Internet Archive circa. 2006): https://web.archive.org/web/20060615083930/http://www.filesuffix.com/browse/browse-1.html
• Filext backup: https://www.fileext.com/

I am sure we looked at these sites during my time on PRONOM, although with less frequency given the need to reduce outline records and increase the number with actionable information.

NB. I also  learned that TrID has been around since 2003! https://web.archive.org/web/20030612031252/http://mark0.ngi.it:80/

Provenance and prior art

It’s not entirely productive to say I wish we had better provenance for PRONOM records back in the day – but I do!

It makes me reflect on the importance of looking outside of our own walls in digital preservation instead of the constant redundancy of reinvention or ownership.

Often as academics, or those with archival views of the world, we can provide a polish and precision to technology as it exists to make it more usable in an archival context.

But cknow has been around so long, and the Unix utility File was created in 1986.

There’s a parallel history here that we should be recognizing and sharing for our next colleagues.

I arrived at TNA in 2009 and learned about File maybe two years later. As a Windows guy at the time, that might not be uncommon, but I do feel it is on me to have known more. I also think it should have been trivial to access the provenance around some of the records in the database at the time, but more than that – as a field, shouldn’t we all know Tom Simondi? What if the same academic rigour of PRONOM and DROID could have been applied to existing tools like File? What if we had expanded our bubble and recognized digital preservation (or the tools for it) is something people have been doing in all but name for the longest time? What if the people working in parallel on these projects and websites were part of the digital preservation inner-circle community today?

I don’t have answers, but I feel there are lessons there for the future. Not reinventing or rebuilding without good reason is important, but even if we build something new and we have been inspired by something else, continuing to recognize and acknowledge prior art is important.

What do you think?

Also, how do we get these people into a room and celebrate their work, and learn more!

What next?

I don’t think I got very far here but I found it interesting, and I hope other readers may as well.

This is meant to be a PRONOM hack-a-thon blog and I don’t know if I have pushed the sticks forward that much but maybe there’s a bit more to reason about in the outline records, for example, around the plain-text formats mentioned above and a few more identified along the way.

I noticed in the outline entries some low-hanging fruit that I might focus on next opportunity if someone else doesn’t get there first, these would be:

A little more on the history of extensions websites

The complete filext text file (allext.zip)

It took a few jumps, but I found the complete downloadable text file from Filext.com. I don’t think it exists any more and I don’t think the internet archive managed to grab a copy. Apparently it was quite a chunk of data to download on the web once upon a time, but they eventually found a way to release a zipped text file:

Via one jump we get to the “whole list” page:

https://web.archive.org/web/20020605164206/http://filext.com/wholelist.htm

And then to confirm our absolute interest in downloading it, we get to the a2z file:

https://web.archive.org/web/20020606071418/http://filext.com/a2z.htm

Which would have taken us to the zip file, alas, never captured on the Internet Archive anyway, maybe it is on other Memento compatible servers:

https://web.archive.org/web/20060117000000*/http://www.filext.com:80/allext.zip

Keeping filext up to date

Filext still asks for registry data to help keep it up to date. That’s pretty cool!

https://filext.com/faq/gather_data_for_filext.html

1 │ Echo OFF
2 │ CLS
3 │ assoc > filext_submission_output.txt
4 │ Echo ---------- >> filext_submission_output.txt
5 │ ftype >> filext_submission_output.txt
6 │ Echo Thank you. The output file has been created and
7 │ Echo named filext_submission_output.txt and it should
8 │ Echo be in the same place where you saved this batch
9 │ Echo file. All that is left now is to send that file
10 │ Echo to FILExt. Attach it to an E-mail sent to the
11 │ Echo address: [email protected]
12 │ Echo The E-mail subject should be: Submission
13 │ Echo Thank you.
14 │ Pause
15 │ Exit

Filext as a source of learning

The filext faqs and community seemed particularly helpful and interesting back in the day:

https://web.archive.org/web/20090322040812/http://filext.com/faq/

File extension aggregator

The file-extension.net website started an aggregator project around 2007 and it’s still running today!

http://file-extension.net/seeker/

Some bonus images…

As I was working on this, I found irony in Google Sheets glitching, I managed to grab some screenshots along the way. Thanks for reading everyone!

#digipres #DigitalPreservation #DROID #FileFormat #FileFormats #PRONOM #WDPD #WDPD2024

simpledroid: completing the circle

It’s nearing the end of 2024 and that must mean a PRONOM hackathon as part of the World Digital Preservation Day (#WDPD2024).

My contribution is a follow-up on my work earlier in the year to produce a valid DROID signature file from Wikidata in wddroidy.

simpledroid is available on GitHub and creates a simple DROID signature file from PRONOM itself, creating a scripted pathway to create a signature file using official PRONOM data that doesn’t require the current PRONOM database and its legacy stored procedures.

It also does away with a lot of the excess data in the current DROID signature file which was previously an optimization for its Boyer Moore Horspool search algorithm, as described by Matthew Palmer.

The primary reason for simpledroid was to complete the circle on my previous efforts and to prove that it was possible to create a simplified signature file and for it to work with DROID. The result is about 80-90% there, with only a few skeleton files that remain unidentified – it should only require a small amount of forensic research to determine the reason.

The output provides a way for simplifying the signature file generation process, offering new opportunities to create alternative versions, or filtering what’s already there, e.g. filtering out any signatures that aren’t explicitly for image identification, e.g. in a digitization workflow.

It may provide another way into PRONOM data for those who might look at DROID first as well as opening up different ways to modify and test signatures.

It is possible to see in the reference output, that the signatures are much easier to understand via this simplified DROID file.

simpledroid outputs a file with a smaller footprint than the current file:

1.2M DROID_SignatureFile_Simple_2024-11-11T12-29-22Z.xml
3.4M DROID_SignatureFile_V118.xml

It also contains all of the file classification data e.g. FormatType="Video" from PRONOM that will be added into DROID in a future release (and is already available in Siegfried).

Unlike the wddroidy work, priorities have also been added to the signature file so the mechanics of the signature file are pretty close to the official version (DROID uses the signature sequence and offsets to identify a file, but it then uses a priority to determine what results to display to the user where there may otherwise be positive matches for formats that provide the foundation for another, e.g. how XML forms the basis of SVG or XHTML.

It might be possible to remove some data around minimum and maximum offsets in the new file after discovering that simplified droid syntax requires curly bracket syntax at the beginning and end of sequences to mimic the same behavior, e.g.

With a BOFoffset, min_offset = 2, and signature = BADF00D1, the signature needs to become {2}BADF00D1 to work.

The code is pretty straightforward and uses a few tricks to output XML sensibly without having to build the document’s tree (DOM) in a more verbose way. There are probably a few other shortcuts I’d fix with time if the code was ever useful, including improving variable naming and adding tests.

I’m not sure this code will ever be needed, or used by anyone, but for a quick hack and a quick proof of concept, it felt good to put it out there. Maybe someone will look at this or the wddroidy work and see there may be a way to federate different sources of signature information together into something DROID can use. Or it might be a useful demonstration to the DROID team that allows them to simplify PRONOM’s database and output mechanisms in a way that remains compatible with existing tools.

Previous research week work

My previous work for PRONOM research week includes a dashboard and API for getting more information out of PRONOM, including listings of those records still requiring descriptions or signatures. You may find that work interesting and it is available at https://pronom.ffdev.info and https://api.pronom.ffdev.info.

And if you want to get in on the signature development work, signature development utility 2.0 (https://ffdev.info) was also a previous effort of mine for research week 2020 and will hopefully also benefit from outputting DROID’s simplified syntax.

A week of file formats

Of course with World Digital Preservation Day, file formats were pretty popular.

Andrew Jackson attempted to calculate how many distinct formats might be out there using methods used to calculate ecological diversity.

Amanda Tome described the scope of their work and shared a number of useful resources including useful links to the PRONOM starter pack and to the PRONOM drop-in sessions.

You might also find out a bit more about yourself by playing this File Format Dating Game from Lotte Wijsman and colleagues: Susanne van den Eijkel, Anton van Es, Elaine Murray, Francesca Mackenzie, Ellie O’Leary, and Sharon McMeekin. (I ended up on a date with FASTA (FDD000622) in my first play-through!)

Not specifically for WDPD, but in the same week I also enjoyed this presentation from Ange Albertini looking at different ways of identifying file formats. One big take away for me was thinking about how to get more forensic information out of a file format identification. DROID doesn’t tell us a lot, but is there a world in which one day it could?

Let me know if you find any of this work useful at all; and good luck on your file format endeavors this week.

#digipres #DigitalPreservation #DROID #FileFormats #PRONOM #Python #siegfried #SkeletonTestCorpus #WDPD #WDPD2024

One of my colleagues wrote a blog on #ipres2024 for #WDPD2024. I was having trouble reaching it yesterday. Maybe there was just too much traffic with all the World Digital Preservation Day excitement. ;) Proud of him for writing -- he is often pretty shy. https://www.dpconline.org/blog/wdpd/blog-lukas-hechenblaickner-wdpd2024

Today's top ten tag trends:

10: #TheHope
9: #ThrowbackThursday
8: #sheepofmastodon
7: #wdpd2024
6: #dydddefaidodon
5: #Defaidodon
4: #defaidodonday
3: #musiquinta
2: #Wissing
1: #carmodelsnamedbykids

#trendytoots 📈

My #WDPD2024 is about setting up slides for https://base4nfdi.de/news-events/events/user-conference-2024, attending the General Assembly of https://4memory.de/ and dipping into one conceptual working group of https://dimag-verbund.de. I am learning a lot! #4memory #nfdi

🌍Dive into the flurry of #digipres blogs for World Digital Preservation Day🌍

Now out: "Finding community on the other side of the world" by Nicola Caldwell of the National Library of New Zealand

https://www.dpconline.org/blog/wdpd/blog-nicola-caldwell-wdpd2024

#WDPD2024 #digitalpreservation #awareness #blogathon #DPCblogs

World Digital Preservation Day also means we'll see #digitalpreservation blogs from the international #digipres community ALL DAY LONG 🎉

Such as this one from Andrea Goethals and Valerie Love about #ipres2025:

Read "Shaping iPRES 2025 Together: Celebrating Community in Aotearoa New Zealand and Beyond" on https://www.dpconline.org/blog/wdpd/blog-goethals-love-wdpd2024

#WDPD2024 #blog #flurry

Que les fêtes commencent! Il est 09h00 en Nouvelle-Zélande, c'est donc officiellement la Journée mondiale de la #préservationnumérique!🌏

Nous commençons par un article de blog de bienvenue de William Kilbride

https://dpconline.org/blog/wdpd/opening-blog-william-kilbride-wdpd2024

Joyeux #WDPD2024 les amis de #digipres !

¡Que empiecen las fiestas! Son las 0900 en Nueva Zelanda, ¡así que es oficialmente el Día Mundial de la #PreservaciónDigital!🌏

Comenzamos con una publicación de blog de bienvenida de William Kilbride

https://dpconline.org/blog/wdpd/opening-blog-william-kilbride-wdpd2024

¡Feliz #WDPD2024 #digipres amigos!

📢 Last chance alert! Only a few spots left for the face-to-face 'Digital Preservation Toolkit for Community Archives' launch in London on Nov 7th! 🏛️🌐

Can't make it? Online registration opens TODAY! Get your tickets here: https://dpconline.org/events/eventdetail/388

#OHOS #WDPD2024 #DigitalPreservation #community #JoinUs