Prof. Dr. Jürgen Döllner
Amir Semmo



Tel.: +49-(0)331 5509-3909
Fax: +49-(0)331 5509-172
Room: H-2.26
Email: amir.semmo(at)hpi.de

Research Interests

Non-Photorealistic Rendering (NPR)
Real-Time Rendering & Shading
Computational Aesthetics
Cartographic Design
Virtual 3D City Models


BeCasso: Artistic Image Processing and Editing on Mobile Devices

Pasewaldt, Sebastian; Semmo, Amir; Döllner, Jürgen; Schlegel, Frank in Proceedings ACM SIGGRAPH Asia Symposium on Mobile Graphics and Interactive Applications (Demo) 2016 .

BeCasso is a mobile app that enables users to transform photos into high-quality, high-resolution non-photorealistic renditions, such as oil and watercolor paintings, cartoons, and colored pencil drawings, which are inspired by real-world paintings or drawing techniques. In contrast to neuronal network and physically-based approaches, the app employs state-of-the-art nonlinear image filtering. For example, oil paint and cartoon effects are based on smoothed structure information to interactively synthesize renderings with soft color transitions. BeCasso empowers users to easily create aesthetic renderings by implementing a two-fold strategy: First, it provides parameter presets that may serve as a starting point for a custom stylization based on global parameter adjustments. Thereby, users can obtain initial renditions that may be fine-tuned afterwards. Second, it enables local style adjustments: using on-screen painting metaphors, users are able to locally adjust different stylization features, e.g., to vary the level of abstraction, pen, brush and stroke direction or the contour lines. In this way, the app provides tools for both higher-level interaction and low-level control [Isenberg 2016] to serve the different needs of non-experts and digital artists. References: Isenberg, T. 2016. Interactive NPAR: What Type of Tools Should We Create? In Proc. NPAR, The Eurographics Association, Goslar, Germany, 89–96
Weitere Informationen
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  • An Interaction Framework for Level-of-Abstraction Visualization of 3D Geovirtual Environments - held at ACM SIGSPATIAL MapInteract 2014, Dallas, TX - USA (11/2014)
  • Image Filtering for Interactive Level-of-Abstraction Visualization of 3D Scenes - held at Expressive 2014, Vancouver - Canada (08/2014)
  • Evaluating the Perceptual Impact of Rendering Techniques on Thematic Color Mappings in 3D Virtual Environments - held at VMV 2013, Lugano - Switzerland (09/2013)
  • Real-Time Rendering of Water Surfaces with Cartography-Oriented Design - held at Expressive 2013, Anaheim, CA - USA (07/2013)
  • Cartography-Oriented Visualization of Virtual 3D City Models based on Level-of-Abstraction Transitions - held at HPI Research School, Potsdam - Germany (06/2012)
  • Interactive Visualization of Generalized Virtual 3D City Models using Level-of-Abstraction Transitions - held at EuroVis 2012, Vienna - Austria (06/2012)
  • Colonia3D - held at Kultur und Informatik Conference, Berlin - Germany (05/2011)
  • Ansätze zur kartographischen Gestaltung von 3D-Stadtmodellen - held at 31. Wissenschaftlich-Technische Jahrestagung der DGPF, Mainz - Germany (04/2011)
  • Automated Image-Based Abstraction of Aerial Images - held at AGILE Conference, Guimarães - Portugal (05/2010)


  • SoSe 2014: Seminar Image & Video Processing
    (with Sebastian Pasewaldt, Matthias Trapp)
  • WiSe 2013/14: Seminar Geovisualization
    (with Rico Richter)
  • SoSe 2013: Graphics Programming with OpenGL and C++
    (with Daniel Limberger, Stefan Buschmann)
  • WiSe 2012/13: Computergrafik II
    (with Daniel Limberger, Jürgen Döllner)
  • SoSe 2012: Exercises for 3D-Computergrafik I
    (with Jan Eric Kyprianidis, Matthias Trapp)
  • WiSe 2011/12: Exercises for Computergrafik II
    (with Matthias Trapp, Christine Lehmann, Jan Eric Kyprianidis)
  • WiSe 2011/12: Seminar Real-Time Rendering Techniques
    (with Rico Richter, Juri Engel)


  • ACM SIGGRAPH (2014)
  • Eurographics Conference on Visualization / EuroVis (2014)
  • IEEE Pacific Visualization (2013)
  • International Journal of Geographical Information Science (2013)
  • The Visual Computer (2012)