GRAPHIS

Geert J. Verhoeven; Martin Wieser; Massimiliano Carloni

doi:10.48619/indigo.v0i0.977

Geert J. Verhoeven University of Vienna - Department of Prehistoric and Historical Archaeology, 1190 Vienna, Austria
Martin Wieser Independent researcher, Vienna, Austria
Massimiliano Carloni Austrian Centre for Digital Humanities and Cultural Heritage, Austrian Academy of Sciences, 1010 Vienna, Austria

DOI: https://doi.org/10.48619/indigo.v0i0.977

Keywords: Annotate, Graffiti-scape, Graffito, GRAPHIS, IPTC, Metadata, Photograph, Polygon

Abstract

A digital photo file contains the image pixel values along with associated photo metadata. Storing those metadata is enabled by various standards. For instance, the Exif standard enables the recording of technical photo metadata like the camera’s serial number and focal length, while the IPTC Photo Metadata Standard is the widely accepted norm for storing copyright and descriptive information in images (from unedited photos to AI-generated pictures). Since its 2019.1 version, the IPTC Photo Metadata Standard has facilitated the creation of image regions: groupings of image pixels—defined by a circle, rectangle, or any other polygonal shape—which can be annotated with region-specific metadata. Given the potential of image regions for graffiti photo annotation, the open-source and freely available software GRAPHIS was developed within the academic graffiti project INDIGO. GRAPHIS (Generate Regions and Annotations for PHotos using the IPTC Standard) allows users to generate and visualise image regions, annotate them with graffiti descriptions or transcriptions, and save them as metadata within the image. To adhere to the IPTC Photo Metadata Standard at every stage, project INDIGO also created a dedicated controlled vocabulary to contain all relevant concepts that can be used to define each image region’s role and content type. This paper starts with a general overview of metadata concepts, followed by a more in-depth look at Exif and IPTC photo metadata. After describing the IPTC Image Region property, the text details the workings of GRAPHIS and the controlled vocabulary development. An overview of use cases and potential software improvements conclude the text.

Author Biographies

Geert J. Verhoeven, University of Vienna - Department of Prehistoric and Historical Archaeology, 1190 Vienna, Austria

Geert J. Verhoeven (°1978) is a senior scientist in archaeology at the University of Vienna (Austria). He received his Master’s and PhD degrees from Ghent University (Belgium) in 2002 and 2009, respectively. Geert is passionately curious about photography, image-based 3D surface modelling, metadata and semantic technologies, spatio-temporal reasoning, colour science, image processing, data visualisation and statistics. His endeavours in these fields aim to improve and standardise data acquisition, data management and information extraction procedures to benefit archaeology and the broader cultural heritage field. From September 2021 to August 2023, Geert took a deep dive into the colourful graffiti world by coordinating project INDIGO. His research output can be found at https://beyondconventionalboundaries.com.

Martin Wieser, Independent researcher, Vienna, Austria

Martin Wieser (°1986) is an independent researcher in photogrammetry and remote sensing. He received his Master’s degree from the Technical University of Vienna (TU Wien, Austria) in 2012. From 2010–2019, Martin worked on many photogrammetry, 3D modelling, remote sensing and data visualisation topics at the TU Wien as a project and university assistant. Since 2016, Martin has also been developing geospatial soft and hardware prototypes for researchers worldwide (Historic England, University of Vienna, Murdoch University Perth).

Massimiliano Carloni, Austrian Centre for Digital Humanities and Cultural Heritage, Austrian Academy of Sciences, 1010 Vienna, Austria

Massimiliano Carloni (°1990) is currently employed at the Austrian Centre for Digital Humanities and Cultural Heritage (Austrian Academy of Sciences) in Vienna. He completed his PhD in Classical Philology at the Scuola Normale Superiore, Pisa (Italy) in 2019 with a thesis on ancient Greek literature. His primary research interest lies in exploring the use of semantic technologies and metadata standards to describe and render accessible vast collections of diverse materials. In particular, he is interested in graph-based data models and linked open data. This led him to join the academic graffiti project INDIGO in November 2021 and take up the challenge of developing technical solutions for the description and long-term digital preservation of the collected data. His research output can be found at https://www.researchgate.net/profile/Massimiliano-Carloni.

GRAPHIS

Visualise, Draw, Annotate, and Save Image Regions in Graffiti Photos

Abstract

Author Biographies