# SIMPLE BUT EFFECTIVE TREE STRUCTURES FOR DYNAMIC PROGRAMMING-BASED STEREO MATCHING

### Michael Bleyer, Margrit Gelautz

#### Abstract

This work describes a fast method for computing dense stereo correspondences that is capable of generating results close to the state-of-the-art. We propose running a separate disparity computation process in each image pixel. The idea is to root a tree graph on the pixel whose disparity needs to be reconstructed. The tree thereby forms an individual approximation of the standard four-connected grid for this specific pixel. An exact optimum of a predefined energy function on the applied tree structure is determined via dynamic programming (DP), and the root pixel is assigned to the disparity of optimal costs. We present two simple tree structures that allow for the efficient calculation of all trees’ optima with only four scanline-based DP passes. These simple trees are designed to capture all pixels of the reference frame and incorporate horizontal and vertical smoothness edges in order to weaken the scanline streaking problem inherent in DP-based approaches. We evaluate our results using the Middlebury test set. Our algorithm currently ranks at the eighth position of approximately 30 algorithms in the Middlebury database. More importantly, it is the currently best-performing method that does not use image segmentation and is significantly faster than most competing algorithms. Our method needs less than a second to determine the disparity map for typical stereo pairs.

#### References

- Birchfield, S. and Tomasi, C. (1998). A pixel dissimilarity measure that is insensitive to image sampling. TPAMI, 20(4):401-406.
- Bleyer, M. and Gelautz, M. (2005). A layered stereo matching algorithm using image segmentation and global visibility constraints. ISPRS Journal, 59(3):128-150.
- Bobick, A. and Intille, S. (1999). Large occlusion stereo. IJCV, 33(3):181-200.
- Boykov, Y., Veksler, O., and Zabih, R. (2001). Fast approximate energy minimization via graph cuts. TPAMI, 23(11):1222-1239.
- Deng, Y. and Lin, X. (2006). A fast line segment based dense stereo algorithm using tree dynamic programming. In ECCV, volume 3, pages 201-212.
- Gong, M. and Yang, Y. (2005). Near real-time reliable stereo matching using programmable graphics hardware. In CVPR, pages 924-931.
- Hirschmüller, H. (2005). Accurate and efficient stereo processing by semi-global matching and mutual information. In CVPR, volume 2, pages 807-814.
- Hirschmüller, H. (2006). Stereo vision in structured environments by consistent semi-global matching. In CVPR, volume 2, pages 2386-2393.
- Kim, J., Lee, K., Choi, B., and Lee, S. (2005). A dense stereo matching using two-pass dynamic programming with generalized ground control points. In CVPR, volume 2, pages 1075-1082.
- Lei, C., Selzer, J., and Yang, Y. (2006). Region-tree based stereo using dynamic programming optimization. In CVPR, volume 2, pages 2378-2385.
- Ogale, A. S. and Aloimonos, Y. (2004). Stereo correspondence with slanted surfaces: critical implications of horizontal slant. In CVPR, pages 568-573.
- Ohta, Y. and Kanade, T. (1985). Stereo by intra- and interscanline search. TPAMI, 7(2):139-154.
- Scharstein, D. and Szeliski, R. (2002). A taxonomy and evaluation of dense two-frame stereo correspondence algorithms. IJCV, 47(1/2/3):7-42. http://www.middlebury.edu/stereo/.
- Sun, J., Zheng, N., and Shum, H. (2003). Stereo matching using belief propagation. TPAMI, 25(7):787-800.
- Veksler, O. (2005). Stereo correspondence by dynamic programming on a tree. In CVPR, pages 384-390.
- Wang, L., Liao, M., Gong, M., Yang, R., and Nister, D. (2006). High quality real-time stereo using adaptive cost aggregation and dynamic programming. In 3DPVT.

#### Paper Citation

#### in Harvard Style

Bleyer M. and Gelautz M. (2008). **SIMPLE BUT EFFECTIVE TREE STRUCTURES FOR DYNAMIC PROGRAMMING-BASED STEREO MATCHING** . In *Proceedings of the Third International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2008)* ISBN 978-989-8111-21-0, pages 415-422. DOI: 10.5220/0001072904150422

#### in Bibtex Style

@conference{visapp08,

author={Michael Bleyer and Margrit Gelautz},

title={SIMPLE BUT EFFECTIVE TREE STRUCTURES FOR DYNAMIC PROGRAMMING-BASED STEREO MATCHING},

booktitle={Proceedings of the Third International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2008)},

year={2008},

pages={415-422},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0001072904150422},

isbn={978-989-8111-21-0},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the Third International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2008)

TI - SIMPLE BUT EFFECTIVE TREE STRUCTURES FOR DYNAMIC PROGRAMMING-BASED STEREO MATCHING

SN - 978-989-8111-21-0

AU - Bleyer M.

AU - Gelautz M.

PY - 2008

SP - 415

EP - 422

DO - 10.5220/0001072904150422