Surface Area Analysis for People Number Estimation

Hiroyuki Arai, Naoki Ito, Yukinobu Taniguchi


An important property of surface areas of objects as observed by a calibrated monocular camera is introduced; also improved techniques to apply the property to people number estimation are proposed. Standard surface area (SSA) is defined as the surface area of the reverse projection of an image-pixel onto a plane at specific height in the real world. SSA is calculated for each pixel according to camera calibration parameters. When the target object is bound to a certain plane, for example the floor plane, the sum of SSA along with the foreground pixels of one target object becomes constant. Therefore, simple foreground detection and SSA summation yield the number of target objects. This basic idea was proposed in a prior article, but there were two major limitations. One is that the original model could not be applied to the area directly below the camera. The other is that the silhouette of the target object was limited to a simple rectangle. In this paper we propose improved techniques that remove the limitations. Slant silhouette analysis removes the first limitation, and silhouette decomposition the second. The validity and the effectiveness of the techniques are confirmed by experiments.


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Paper Citation

in Harvard Style

Arai H., Ito N. and Taniguchi Y. (2014). Surface Area Analysis for People Number Estimation . In Proceedings of the 9th International Conference on Computer Vision Theory and Applications - Volume 2: VISAPP, (VISIGRAPP 2014) ISBN 978-989-758-004-8, pages 86-93. DOI: 10.5220/0004687000860093

in Bibtex Style

author={Hiroyuki Arai and Naoki Ito and Yukinobu Taniguchi},
title={Surface Area Analysis for People Number Estimation},
booktitle={Proceedings of the 9th International Conference on Computer Vision Theory and Applications - Volume 2: VISAPP, (VISIGRAPP 2014)},

in EndNote Style

JO - Proceedings of the 9th International Conference on Computer Vision Theory and Applications - Volume 2: VISAPP, (VISIGRAPP 2014)
TI - Surface Area Analysis for People Number Estimation
SN - 978-989-758-004-8
AU - Arai H.
AU - Ito N.
AU - Taniguchi Y.
PY - 2014
SP - 86
EP - 93
DO - 10.5220/0004687000860093