results

INDIGO is an open-data and open-access project, operating according to the FAIR principles. Whereas all project data will become available at the project’s end via the ARCHE data repository, any scientific output can be found at different locations:

  • INDIGO’s Zenodo community
  • a dedicated ResearchGate project page
  • here! Below, one finds all relevant info and links to INDIGO’s soft- and hardware, oral and poster presentations, publications and symposia. Each section is directly accessible via the menu above.

software

The INDIGO team created AUTOGRAF, COOLPI and GRAPHIS, three software packages that are free to download from INDIGO’s GitHub account.

  • AUTOGRAF (AUTomated Orthorectification of GRAFfiti photos) is an open-source python-based Metashape add-on to automatically orthorectify (graffiti)  photos. Its source code can be found here.
  • the COlour Operations Library for Processing Images (COOLPI) is an open-source Python toolbox including procedures for the colour correction of RAW photos. The code comes with an extensive manual.
  • GRAPHIS (Generate Regions and Annotations for Photos using the IPTC Standard) is an open-source python-based software to create, visualise and annotate image regions and store them inside the image metadata according to the IPTC photo metadata standard. The source code is available here.

hardware

The INDIGO team has developed a device to record the camera’s exact 3D position and angular rotation in space at the moment of photo acquisition. This so-called exterior orientation is helpful for accurately locating the photos and significantly speeds up their processing.

Built from commercially available but cost-effective components in a 3D printed housing, this device connects to the hot shoe on top of the camera.

It receives a real-time kinematic correction signal from the Austrian EPOSA service (Echtzeit-Positionierung-Austria) to increase the accuracy of coordinates collected via satellite-based positioning systems like the American GPS or European GALILEO constellations.

All settings of the on-camera device get wirelessly controlled from any browser running on a tablet or smartphone. In addition, four status LEDs provide the user instant feedback on anything that’s going on with the device. A thorough assessment of this novel hardware solution will be reported in a future paper.

scientific publications

So far, INDIGO has published three peer-reviewed journal papers, one edited proceedings volume and eight conference papers.

  • Merrill, S., Verhoeven, G.J., Wild, B., JANER ONE, MANUEL SKIRL, SERT, SNUF, Carloni, M., de la Iglesia, M., Fernandez Merino, F., Radošević, L., Ricci, C., Schlegel, J., Wogrin, S., 2023. ‘Different folks, different strokes’: goINDIGO 2022’s «Creators vs Academics» discussion round, in: document | archive | disseminate graffiti-scapes. Proceedings of the goINDIGO2022 international graffiti symposium, Vienna, Austria, 11-13 May 2022. Urban Creativity, Lisbon, pp. 25-44. DOI: 10.48619/indigo.v0i0.701
  • Molada-Tebar, A., Verhoeven, G.J., 2023. Towards colour-accurate documentation of anonymous expressions, in: document | archive | disseminate graffiti-scapes. Proceedings of the goINDIGO2022 international graffiti symposium, Vienna, Austria, 11-13 May 2022. Urban Creativity, Lisbon, pp. 86-130. DOI: 10.48619/indigo.v0i0.704
  • Nocerino, E., Menna, F., Verhoeven, G.J., 2022. Good vibrations? How image stabilisation influences photogrammetry. Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci. XLVI-2/W1-2022, 395–400. DOI: 10.5194/isprs-archives-XLVI-2-W1-2022-395-2022
  • Schlegel, J., Carloni, M., Wogrin, S., Verhoeven, G.J., 2022. Making a mark—Towards a graffiti thesaurus, in: document | archive | disseminate graffiti-scapes. Proceedings of the goINDIGO2022 international graffiti symposium, Vienna, Austria, 11-13 May 2022. Urban Creativity, Lisbon, pp. 203-219. DOI: 10.48619/indigo.v0i0.710
  • Verhoeven, G.J., Carloni, M., Schlegel, J., Wild, B., Wogrin, S., 2022. Finding listeners for walls that speak, in: document | archive | disseminate graffiti-scapes. Proceedings of the goINDIGO2022 international graffiti symposium, Vienna, Austria, 11-13 May 2022. Urban Creativity, Lisbon, pp. 6-15. DOI: 10.48619/indigo.v0i0.699
  • Verhoeven, G.J., Schlegel, J., Wild, B., Wogrin, S., Carloni, M. (Eds.), 2022. document | archive | disseminate graffiti-scapes. Proceedings of the goINDIGO2022 international graffiti symposium. Urban Creativity, Lisbon. ISBN: 979-8394601279
  • Verhoeven, G.J., Wild, B., Schlegel, J., Wieser, M., Pfeifer, N., Wogrin, S., Eysn, L., Carloni, M., Koschiček-Krombholz, B., Molada-Tebar, A., Otepka-Schremmer, J., Ressl, C., Trognitz, M., Watzinger, A., 2022. Project INDIGO – document, disseminate & analyse a graffiti-scape. Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci. XLVI-2/W1-2022, 513–520. DOI: 10.5194/isprs-archives-XLVI-2-W1-2022-513-2022. This article won the best paper award at the 3D-ARCH 2022 conference.
  • Verhoeven, G.J., Wogrin, S., Schlegel, J., Wieser, M., Wild, B., 2022. Facing a chameleon—How project INDIGO discovers and records new graffiti, in: document | archive | disseminate graffiti-scapes. Proceedings of the goINDIGO2022 international graffiti symposium, Vienna, Austria, 11-13 May 2022. Urban Creativity, Lisbon, pp. 63-85. DOI: 10.48619/indigo.v0i0.703
  • Wild, B., Verhoeven, G.J., Pfeifer, N., Bonadio, E., DEADBEAT HERO, FUNKY, JANER ONE, MANUEL SKIRL, Carloni, M., Ricci, C., Koblitz, C., Niemann, S., Radošević, L., Schlegel, J., Watzinger, A., Wogrin, S., 2022. ‘Imagine being a racist’: goINDIGO 2022’s «Ethics & legality in graffiti (research)» discussion round, in: document | archive | disseminate graffiti-scapes. Proceedings of the goINDIGO2022 international graffiti symposium, Vienna, Austria, 11-13 May 2022. Urban Creativity, Lisbon, pp. 45-62. DOI: 10.48619/indigo.v0i0.702
  • Wild, B., Verhoeven, G.J., Wieser, M., Ressl, C., Schlegel, J., Wogrin, S., Otepka-Schremmer, J., & Pfeifer, N., 2022. AUTOGRAF—Automated Orthorectification of GRAFfiti Photos. Heritage, 5(4), 2987–3009. DOI: 10.3390/heritage5040155
  • Wild, B., Verhoeven, G.J., Wieser, M., Ressl, C., Otepka-Schremmer, J., Pfeifer, N., 2023. Graffiti-Dokumentation: Projekt INDIGO, in: 22. Internationale Geodätische Woche Obergurgl 2023, Obergurgl, Austria. 12-18 February 2023. Wichmann, Berlin, pp. 322–325. DOI: 10.5281/zenodo.7715655
  • Wild, B., Verhoeven, G.J., Wogrin, S., Wieser, M., Otepka-Schremmer, J., Pfeifer, N., 2022. Urban Creativity meets Engineering. Automated Graffiti Mapping along Vienna’s Donaukanal, in: document | archive | disseminate graffiti-scapes. Proceedings of the goINDIGO2022 international graffiti symposium, Vienna, Austria, 11-13 May 2022. Urban Creativity, Lisbon, pp. 131-145. DOI: 10.48619/indigo.v0i0.705

As of May 2023, one conference paper is submitted:

  • Wild, B., Verhoeven, G.J., Pfeifer, N., 2022. Tracking the urban chameleon – Towards a hybrid change detection of graffiti. CIPA2023, the 29th CIPA-HD biennial Symposium, 26-30 June 2023, Florence, Italy. (accepted)

scientific presentations – talks

Below, all eleven scientific talks on INDIGO-specific topics are listed. If the presentation is available online, it got a DOI number over Zenodo. Certain presentations do not feature a DOI, because the content was (almost) identical to previous talks.

  • 17/09/2021 [Vienna, Austria]
    • Meeting/conference: Second Heritage Science Austria Meeting
    • Title: INDIGO: INventory and DIsseminate Graffiti along the dOnaukanal
    • Presenter: Geert Verhoeven
    • Invited: Yes
    • DOI: 10.5281/zenodo.6338834
  • 19/11/2021 [Online, Austria]
    • Meeting/conference: Meeting Ethical commission TU Wien
    • Title: INDIGO: INventory and DIsseminate Graffiti along the dOnaukanal
    • Presenter: Geert Verhoeven
    • Invited: No
  • 25/11/2021 [Vienna, Austria]
    • Meeting/conference: Internal meeting at the PhotoCircle research group (Geodesy Department TU Wien, Austria)
    • Title: Photogrammetry in context of the graffiti-research project INDIGO
    • Presenter: Benjamin Wild
    • Invited: No
  • 02/03/2022 [Mantova, Italy]
    • Meeting/conference: 3D-ARCH’2022 – 3D Virtual Reconstruction and Visualization of Complex Architectures – 9th International Workshop
    • Title: Project INDIGO – document, disseminate & analyse a graffiti-scape
    • Presenter: Benjamin Wild
    • Invited: No
    • DOI: 10.5281/zenodo.6339489
  • 03/03/2022 [Mantova, Italy]
    • Meeting/conference: 3D-ARCH’2022 – 3D Virtual Reconstruction and Visualization of Complex Architectures – 9th International Workshop
    • Title: Good vibrations? How image stabilisation influences photogrammetry
    • Presenter: Fabio Menna
    • Invited: No
    • DOI: 10.5281/zenodo.6382756
  • 31/03/2022 [Online, Australia]
    • Meeting/conference: Pointcloud Workshop (Geospatial Research Innovation Development lab at the University of New South Wales)
    • Title: Project INDIGO – document, disseminate & analyse a graffiti-scape
    • Presenter: Benjamin Wild
    • Invited: Yes
  • 11/05/2022 [Vienna, Austria]
    • Meeting/conference: goINDIGO 2022: document | archive | disseminate graffiti-scapes
    • Title: Discovering & recording new graffiti within project INDIGO
    • Presenter: Geert Verhoeven
    • Invited: No
    • DOI: 10.5281/zenodo.6574796
  • 11/05/2022 [Vienna, Austria]
    • Meeting/conference: goINDIGO 2022: document | archive | disseminate graffiti-scapes
    • Title: Achieving colour-accurate data from images: challenges and solutions
    • Presenter: Adolfo-Molada Tebar
    • Invited: No
    • DOI: 10.5281/zenodo.6579429
  • 12/05/2022 [Vienna, Austria]
    • Meeting/conference: goINDIGO 2022: document | archive | disseminate graffiti-scapes
    • Title: Towards a graffiti thesaurus in SKOS
    • Presenter: Jona Schlegel & Massimiliano Carloni
    • Invited: No
    • DOI: 10.5281/zenodo.6578470
  • 12/05/2022 [Vienna, Austria]
    • Meeting/conference: goINDIGO 2022: document | archive | disseminate graffiti-scapes
    • Title: Towards the automatic production of graffiti orthophotos
    • Presenter: Benjamin Wild
    • Invited: No
    • DOI: 10.5281/zenodo.6574990
  • 07/07/2022 [Wrocław, Poland]
    • Meeting/conference: Guest lecture
    • Title: INDIGO – document, disseminate & analyse a graffiti-scape
    • Presenter: Norbert Pfeifer
    • Invited: Yes

scientific presentations – posters

Two posters on INDIGO-specific topics have been produced since the project’s start:

  • 23/09/2022 [Vienna, Austria]
    • Meeting/conference: Third Heritage Science Austria Meeting
    • Title: Acquiring centimetre-accurate camera coordinates in project INDIGO
    • Presenter: Geert Verhoeven
    • Invited: No
    • DOI: 10.5281/zenodo.7109573
  • 23/09/2022 [Vienna, Austria]
    • Meeting/conference: Third Heritage Science Austria Meeting
    • Title: How project INDIGO automatically turns graffiti photos into orthophotomaps
    • Presenter: Benjamin Wild
    • Invited: No
    • DOI: 10.5281/zenodo.7109431
  • 17/02/2023 [Obergurgl, Austria]
    • Meeting/conference: 22. Internationale Geodätische Woche
    • Title: Graffiti Dokumentation: Projekt INDIGO
    • Presenter: Benjamin Wild
    • Invited: No
    • DOI: 10.5281/zenodo.7638295

symposia | workshops

Because INDIGO has a technical- and more humanistic-oriented aspect, both aspects were from the beginning planned to be covered by two symposia. Although the COronaVIrus Disease 2019 (COVID-19) was still wreaking havoc across the world, the hope was nurtured to physically bring together specific subsections of the (scholarly) graffiti community in Vienna. The initial timing of both symposia accounted for INDIGO’s project schedule to maximise the relevancy of the discussions and insights gained.

  • goINDIGO2022 had been planned to take place six months into the project and tackle all the technical, logistic, legal, and ethical aspects of documenting, archiving, and disseminating graffiti. The idea of gathering experts and experience so early was to help avoid pitfalls on various more technical topics further down INDIGO’s road. Although the uncertainty created by the COVID-19 pandemic slightly delayed the goINDIGO 2022 symposium and made a hybrid event inevitable, INDIGO managed a small but successful gathering. From the 11th to the 13th of May, a mixed group of sixty participants (graffiti creators, heritage professionals and graffiti academics) from twelve countries met in Vienna or online to learn from each other and build proverbial bridges. Throughout two and a half days, two keynote lectures and eighteen presentations touched upon many facets of documenting, archiving and disseminating graffiti records (see also the book of abstracts). The goINDIGO 2022 proceedings will normally be published before the end of 2022 as an UrbanCreativity open-access volume.
  • A second symposium – goINDIGO 2023 – is planned for the end of the project (see also the symposium website). This gathering should focus on graffiti’s socio-political and cultural impact. goINDIGO 2023 will also mark the launch of INDIGO’s online platform and showcase how its stored graffiti (meta)data enables societal and cultural insights. In this way, specialists in art history, philosophy, cultural studies, law, urbanism, psychology, and communication will see the potential of this massive open-access archive, thereby ensuring this project’s transdisciplinary sustainability.
  • On the 25th of June 2023, Geert (and likely Adolfo) will give a workshop on colourimetric processing of digital photos. This workshop takes place at the start of the CIPA heritage Documentation conference in Florence, Italy. The workshop will use the COOLPI software package developed within the INDIGO project.