# DIRECT COMPUTATION OF DEPTH FROM SHADING FOR PERSPECTIVE PROJECTION

### Kousuke Wakabayashi, Norio Tagawa, Kan Okubo

#### Abstract

We present a method for recovering shape from shading in which the surface depth is directly computed. The already proposed method solving the same problem assumes that images are captured under the parallel projection, and hence, it can be correctly used only for the relative thin objects compared with the distance from the camera. If this method is formally extended for the perspective projection completely, the complicated calculations for differential are required. This gives rise to unstable recovery. In this study, we examine an extension of this method so as to treat the perspective projection approximately. In order to keep the simplicity of the original method, we propose the simple approximation of the derivative of the surface with respect to the image coordinate.

#### References

- TH 0.03
- FDO 0.025
- SRM 0.02
- Press, W. H., Flannery, B. P., Teukolsky, S. A., and Vetterling, W. T. (1986). Numerical methods, the art of scientific computing. Cambridge U. Press, Cambridge, MA.

#### Paper Citation

#### in Harvard Style

Wakabayashi K., Tagawa N. and Okubo K. (2012). **DIRECT COMPUTATION OF DEPTH FROM SHADING FOR PERSPECTIVE PROJECTION** . In *Proceedings of the International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2012)* ISBN 978-989-8565-03-7, pages 445-448. DOI: 10.5220/0003854804450448

#### in Bibtex Style

@conference{visapp12,

author={Kousuke Wakabayashi and Norio Tagawa and Kan Okubo},

title={DIRECT COMPUTATION OF DEPTH FROM SHADING FOR PERSPECTIVE PROJECTION},

booktitle={Proceedings of the International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2012)},

year={2012},

pages={445-448},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0003854804450448},

isbn={978-989-8565-03-7},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2012)

TI - DIRECT COMPUTATION OF DEPTH FROM SHADING FOR PERSPECTIVE PROJECTION

SN - 978-989-8565-03-7

AU - Wakabayashi K.

AU - Tagawa N.

AU - Okubo K.

PY - 2012

SP - 445

EP - 448

DO - 10.5220/0003854804450448