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“15 SECONDS OF FAME” Use of Computer Vision in a Modern Art Installation. Franc Solina. Computer Vision Laboratory Faculty of Computer and Information Science University of Ljubljana , Slovenia. Motivation for this work.
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“15 SECONDS OF FAME”Use of Computer Vision in a Modern Art Installation Franc Solina Computer Vision Laboratory Faculty of Computer and Information Science University of Ljubljana, Slovenia
Motivation for this work • collaboration with the Academy of Fine Arts in Ljubljana since 1995 • new media, computer-based art installations (internet, virtual galleries, video, mobile robots, remote operation) • work of scientist and conceptual artist Ken Goldberg, UC Berkeley (TELEGARDEN) • COMPUTER VISION + ART INSTALLATION = ?
Video cameras in art installations • wooden mirror (Daniel Rozin) • touch me (Alba d’Urbano) • liquid views (Monika Fleischman) • … • TECHNICAL LIMITATIONS: precise positioning of the subject
“In the future everybody will befamous for 15 minutes.”Andy Warhol Marilyn Monroe (Andy Warhol, 1964)
Image mediated culture • people like to look at themselves (mirrors, photos, paintings, video) • vanity, self-discovery, self-assertion • a face in mass culture -> FAME • media attention - a mirror of the indivudual’s self-perception • WARHOL: celebrity photo -> portrait • warhol-like portrait -> instant celebrity
Faces in computer vision • images of people • find people, identify them, determine their activity • video surveillance • face recognition <- FACE DETECTION
Hardware LCD monitor Digital camera computer USB
learning 15 second loop Software input photo illumination compensation find faces + randomly select one transformation color filters pop-art portrait
Roadmap • color-based face detection • illumination compensation • pop-art color transformations • display and ordering of portraits over the Internet • conclusions
Simplified face detection 2 • ADVANTAGES: faster, detected also faces from profile • DISADVANTAGES: faces of dark complexion not detected, other body parts can be detected
Eliminating the influence of non-standard illumination • different from daylight illumination • color constancy/compensation methods • eestimate the present illumination • reconstruct the image under standard illumination • run face detection algorithm
Color compensation methods • close to standard illumination • low time complexity • Grey World • Average surface color in the image is achromatic • Illumination estimation: average color • Mean gray value • Modified Grey World • Illumination estimation: each color is counted only once • White-Patch Retinex • On each image white surface is present • Illumination estimation: maximal color
Color compensation methods NO – original GW – Gray World MGW – Modified GW RET – White-Patch Retinex NO GW MGW RET
Color constancy methods • far from standard illumination • Color by Correlation • (1) LEARNING: Take images of the Macbeth color checker under present illum. and under standard illum. • Use correlation to compute the transform. Parameters • (2) APPLY TRANSFORMATION
Color comp. + correll. method NO GW MGW RET COR NO – original GW – Gray World MGW – Modified GW RET – White-Patch Retinex COR – Color by Correlation
Warhol’s celebrity portraits • segment the face from the background • delineate the contours • highlight some facial features (mouth, eyes, hair) • overlay with color screens • above transformations -> shape grammar • BUT: requires automatic segmentation into constituent face parts
pop-art color filters • color-balance • posterize • color-balance • posterize • hue-saturation • hue-saturation • 17 universal filters • random coloring
Display of portraits • different configurations • 1 big portrait • 4 smaller portraits • same filter • each with a different filter • horizontal flip • each time a different person • no detection -> last detected face with a different pop-art filter • 15 second counter
E-mail ordering of portraits • Beside the portrait is displayed an unique ID number • Sending e-mail to • Sending the requested picture Creating of the web page 15sec@lrv.fri.uni-lj.si Ordering system
The gallery of “famous” people from the project web page: black.fri.uni-lj.si/15sec
Audience interactions • people quickly realize that portraits of people present at the moment are displayed • if several people are present, becoming famous is elusive • subtle staging to get one’s most favourable image on the screen • subdued competition for “media” attention • narcissistic and voyeristic use of the “electronic mirror”
Exhibitions in art galleries • Forum Stadtpark, Graz, Austria, 19-26 Sep. 2003 • Finzgar Gallery, Ljubljana, 14-26 Nov. 2002 • 8th International Festival of Computer Arts, Maribor, 28 May-1 June 2002
Conclusions • well accepted by the audience • no visible interface • a group of people can interact at once • exact positioning of observers not necessary • at least one face should be found in the input image • -> high percentage of true positive face detections • -> percentage of true negative face detections can be low • a huge database for testing face detection is generated • The goal was not to mimic Andy Warhol’s portraits per se but to play upon the celebrification process and the discourse taking place in front of the installation.