HACK4DK 2017

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The HACK4DK is an annual event in Copenhagen, bringing together cultural nerds and computer nerds for building interesting things with cultural data. I have been participating since the very beginning and participated in this year’s HACK4DK which took place at ENIGMA, a to-be museum in Østerbro, Copenhagen.

The winning project among around 19 projects this year was Tin Toy, a neat augmented reality application using images from the toy collection of Holstebro Museum. I believe they used the AR.js Javascript library. There is a YouTube video that attempts to capture the attractiveness of the project:

The result of my struggles with the a-frame Javascript library is available on this page: https://fnielsen.github.io/hack4dk2017/. Under the name “Virtual Gallery of Denmark” it was suppose to be a virtual reality environment with presentation of Danish art. The end result became a somewhat less dynamic but meditative environment with textured panels flying around in a virtual environment and with sound from old rerecorded phonographs in the Ruben Collection made available by the Royal Library in Aarhus.


I did not rely on the data provided at the event, but used data from the cultural institutions that were already uploaded to Wikimedia Commons and where the metadata was described on Wikidata. Both the images of the paintings (which was from Skagens Museum) and the sound were available at Wikimedia Commons and well-annotated on Wikidata.

The images was fetched with SPARQL queries to the Wikidata Query Service and API calls to the Wikimedia Commons API, and as such it is fairly easy to change the virtual environment to use other files which I did afterwards: The Giersing-Bach-Ishizaka-Nielsen virtual environment uses images on Wikimedia Commons where Wikidata records the artist as being Harald Giersing. Here the sound is from the Kimiko Ishizaka‘s Open Goldberg Variations project.


While a-frame models are suppose to run straight from the web browser on smartphones, my models seem to have hefty hardware requirements, – the images have quite high resolutions. It takes over 10 seconds on my computer to download all the image and sound files associated with the models. Nevertheless, with a strong computer, a big screen and good headphones, it is quite interesting to view and hear as the paintings and sound fly by.


The mystery of the rotating building

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For hack4dk I found old images on Wikimedia Commons of scenes in central Copenhagen and took photos of the same places. One of old images was called Bibliotekspladsen 1913. The image is supposedly from 1913 and printed in “Forskønnelsen” magazine in 1923. It has been uploaded to Wikimedia Commons by user Saddhiyama, who writes that the photo is from the library garden. I went to the garden, took a photo and blended the two images with the result shown on Bibliotekspladsen remixed. It was slightly difficult to match my photo with the old image as trees covered the buildings in the new photo.

What is strange with the old photo is the small building to the left:

  1. In old maps you see buildings parallel to the long building, see, e.g., a reconstruction(?) of a 1725 map
  2. In a photo from 1880 a building is now orthogonal to the long building (if this is the same spot!?)
  3. In the photo from 1913 a building (the “provianthusforvalterbolig”) is now parallel to the long building.
  4. Now you can go (also with Google Maps) and see that a building is orthogonal to the long builing.

So what is the most likely: That the images do not display the same location or that they have demolished the building, rebuilt, demolished, rebuilt, demolish and rebuilt?

To make it more strange you can go the red house hiding in the corner (with Google Maps). There you can read above the door that the building is from 1818. Looking at the 1913 image it is difficult to imaging how you can get room for the red house between the other houses.

Kultorvet remixed

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Yet another Paul Fischer remix.

Jailhouse remixed: Now with complete skilderhus

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For recent hack4dk I made photographs from the same viewpoint as some classical paintings and blended the original image with the new photo. My first attempt with the old Copenhagen Jailhouse was not completely satisfactory. One problem was with the guards red skilderhus at the right side of the image. I have now corrected this. Another problem was with the road sign that in my original remixed image floated in midair. I also exposed the lamp in the middle of the image a bit better.

Hack4dk contributions

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Ten projects was shown at the final showdown:

  • Kræn‘s (with help from Emma) Natmus Mosaic with autocropping and search facility. Code available from Github
  • Kim Bach and … Game with Daell’s Varehus catelogue: try to guess the decade
  • Henrik, Andreas and …(?), mail art mail box.
  • Mobil app with public art. List of nearby art shown with photos and on maps.
  • Public art search engine
  • Search engine and viewer for Copenhagen Police “Mandtaller”. Machine vision in Javascript.
  • Rasmus Erik: Wikipedia link visualization, image extract with classification og the Police images, quiz with decade. http://www.solsort.com
  • Heat map movie through time of Copenhageners
  • SMK image visualization.
  • Steen Thomassen: Join the Danish Wikipedia and the Danish film database, e.g., for Tommy Kenter. The useful tool is running from Wikimedia Labs server.

Winner became the heatmap movie with Kræn’s Natmus Mosaic viewer as runner up.

Fishy fishmongers of Fischer

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Danish painter Paul Fischer painted urban scences from Copenhagen. One of them is a painting with the fishmongers from Gammelstrand.