Abstract
Many crowd analysis methods rely on optical flow techniques to estimate the main moving directions. In this work, we propose a crowd flow filtering approach for calibrated cameras that can be coupled to any generic optical flow method. It projects the input optical flow to the world coordinate system, performs a local motion analysis exploring a Social Forces Model and then projects the filtered flow back onto the image plane. The method was tested on publicly available datasets involving crowded scenarios used in conjunction with different optical flow methods, and results indicate that the proposed filtering method provides coherent crowd flows when coupled to the tested methods.
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Abdallah, A.C.B., Gouiffès, M., Lacassagne, L.: A modular system for global and local abnormal event detection and categorization in videos. Mach. Vis. Appl. 27(4), 463–481 (2016). https://doi.org/10.1007/s00138-016-0752-z
Ali, S., Shah, M.: Floor fields for tracking in high density crowd scenes. In: Proceedings of the 10th European Conference on Computer Vision: Part II, ECCV’08, pp. 1–14. Springer, Berlin (2008). https://doi.org/10.1007/978-3-540-88688-4_1
Baker, S., Scharstein, D., Lewis, J., Roth, S., Black, M.J., Szeliski, R.: A database and evaluation methodology for optical flow. Int. J. Comput. Vis. 92(1), 1–31 (2011)
Bouguet, J.Y.: Pyramidal implementation of the affine lucas kanade feature tracker description of the algorithm. Intel Corp. 5(1–10), 4 (2001)
Bradski, G.: Opencv: examples of use and new applications in stereo, recognition and tracking. In: Proc. of International Conference on Vision Interface (2002)
Brox, T., Malik, J.: Large displacement optical flow: descriptor matching in variational motion estimation. IEEE Trans. Pattern Anal. Mach. Intell. 33(3), 500–513 (2011)
Chen, D.Y., Huang, P.C.: Motion-based unusual event detection in human crowds. J. Vis. Commun. Image Represent. 22(2), 178–186 (2011)
Cheriyadat, A.M., Radke, R.J.: Detecting dominant motions in dense crowds. IEEE J. Sel. Top. Signal Process. 2(4), 568–581 (2008)
de Almeida, I.R., Jung, C.R.: Change detection in human crowds. In: 2013 26th SIBGRAPI-Conference on Graphics, Patterns and Images (SIBGRAPI), pp. 63–69. IEEE (2013)
de Almeida, I.R., Cassol, V.J., Badler, N.I., Musse, S.R., Jung, C.R.: Detection of global and local motion changes in human crowds. IEEE Trans. Circuits Syst. Video Technol. 27(3), 603–612 (2017)
Dosovitskiy, A., Fischer, P., Ilg, E., Hausser, P., Hazirbas, C., Golkov, V., Van Der Smagt, P., Cremers, D., Brox, T.: Flownet: learning optical flow with convolutional networks. In: Proceedings of the IEEE International Conference on Computer Vision, pp. 2758–2766 (2015)
Farnebäck, G.: Two-frame motion estimation based on polynomial expansion. In: Image Analysis, pp. 363–370 (2003)
Fortun, D., Bouthemy, P., Kervrann, C.: Optical flow modeling and computation: a survey. Comput. Vis. Image Underst. 134, 1–21 (2015). https://doi.org/10.1016/j.cviu.2015.02.008.
Hall, E.T.: The Hidden Dimension, vol. 609. Doubleday, Garden City, NY (1966)
He, K., Sun, J., Tang, X.: Guided image filtering. IEEE Trans. Pattern Anal. Mach. Intell. 35(6), 1397–1409 (2013)
Helbing, D., Molnár, P.: Self-organization phenomena in pedestrian crowds. In: Self-organization of Complex Structures: From Individual to Collective Dynamics. Citeseer, Princeton (1997)
Helbing, D., Farkas, I., Vicsek, T.: Simulating dynamical features of escape panic. Nature 407(6803), 487–490 (2000)
Horn, B.K., Schunck, B.G.: Determining optical flow. Artif. Intell. 17(1–3), 185–203 (1981)
Hui, T.W., Tang, X., Change Loy, C.: Liteflownet: a lightweight convolutional neural network for optical flow estimation. In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pp. 8981–8989 (2018)
Ilg, E., Mayer, N., Saikia, T., Keuper, M., Dosovitskiy, A., Brox, T.: Flownet 2.0: evolution of optical flow estimation with deep networks. In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pp. 2462–2470 (2017)
Jung, C.R.: Efficient background subtraction and shadow removal for monochromatic video sequences. IEEE Trans. Multimed 11(3), 571–577 (2009)
Kajo, I., Malik, A.S., Kamel, N.: An evaluation of optical flow algorithms for crowd analytics in surveillance system. In: 2016 6th International Conference on Intelligent and Advanced Systems (ICIAS), pp. 1–6 (2016). https://doi.org/10.1109/ICIAS.2016.7824064
Kajo, I., Kamel, N., Malik, A.S.: An adaptive block-based matching algorithm for crowd motion sequences. Multimed. Tools Appl. (2017). https://doi.org/10.1007/s11042-016-4327-9
Kratz, L., Nishino, K.: Anomaly detection in extremely crowded scenes using spatio-temporal motion pattern models. In: IEEE Conference on Computer Vision and Pattern Recognition, 2009. CVPR 2009, pp. 1446–1453. IEEE (2009)
Kusakunniran, W., Li, H., Zhang, J.: A direct method to self-calibrate a surveillance camera by observing a walking pedestrian. In: 2009 Digital Image Computing: Techniques and Applications, pp. 250–255. IEEE (2009)
Lim, M.K., Kok, V.J., Loy, C.C., Chan, C.S.: Crowd saliency detection via global similarity structure. In: 2014 22nd International Conference on Pattern Recognition, pp. 3957–3962 (2014)
Liu, C., Freeman, W.T., Adelson, E.H., Weiss, Y.: Human-assisted motion annotation. In: 2008 IEEE Conference on Computer Vision and Pattern Recognition, pp. 1–8 (2008)
Lucas, B.D., Kanade, T.: An iterative image registration technique with an application to stereo vision. In: Proceedings of the 7th International Joint Conference on Artificial Intelligence, pp. 674–679. Morgan Kaufmann Publishers, Burlington (1981)
Mehran, R., Oyama, A., Shah, M.: Abnormal crowd behavior detection using social force model. In: 2009 IEEE Conference on Computer Vision and Pattern Recognition, pp. 935–942 (2009)
Mousavi, H., Mohammadi, S., Perina, A., Chellali, R., Murino, V.: Analyzing tracklets for the detection of abnormal crowd behavior. In: 2015 IEEE Winter Conference on Applications of Computer Vision (WACV), pp. 148–155. IEEE (2015)
Moussaïd, M., Helbing, D., Theraulaz, G.: How simple rules determine pedestrian behavior and crowd disasters. Proc. Nat. Acad. Sci. 108(17), 6884–6888 (2011)
Renno, J., Orwell, J., Jones, G.A.: Learning surveillance tracking models for the self-calibrated ground plane. In: BMVC, pp. 1–10 (2002)
Rodriguez, M., Laptev, I., Sivic, J., Audibert, J.Y.: Density-aware person detection and tracking in crowds. In: 2011 IEEE International Conference on Computer Vision (ICCV), pp. 2423–2430. IEEE (2011)
Shi, J., et al.: Good features to track. In: Proceedings of1994 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 1994. CVPR’94, pp. 593–600. IEEE (1994)
Solmaz, B., Moore, B.E., Shah, M.: Identifying behaviors in crowd scenes using stability analysis for dynamical systems. IEEE Trans. Pattern Anal. Mach. Intell. 34(10), 2064–2070 (2012)
Sun, D., Roth, S., Black, M.J.: Secrets of optical flow estimation and their principles. In: 2010 IEEE Conference on Computer Vision and Pattern Recognition (CVPR), pp. 2432–2439. IEEE (2010)
Sun, D., Roth, S., Black, M.J.: A quantitative analysis of current practices in optical flow estimation and the principles behind them. Int. J. Comput. Vis. 106(2), 115–137 (2014)
Tu, Z., Xie, W., Zhang, D., Poppe, R., Veltkamp, R.C., Li, B., Yuan, J.: A survey of variational and CNN-based optical flow techniques. Signal Process. Image Commun. 72, 9–24 (2019)
Tuzel, O., Porikli, F., Meer, P.: Region covariance: a fast descriptor for detection and classification. In: European Conference on Computer Vision. Springer, pp. 589–600 (2006)
Weinzaepfel, P., Revaud, J., Harchaoui, Z., Schmid, C.: Deepflow: large displacement optical flow with deep matching. In: 2013 IEEE International Conference on Computer Vision, pp. 1385–1392 (2013). https://doi.org/10.1109/ICCV.2013.175
Wu, S., Moore, B.E., Shah, M.: Chaotic invariants of Lagrangian particle trajectories for anomaly detection in crowded scenes. In: The Twenty-Third IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2010, San Francisco, CA, USA, 13–18 June 2010, pp. 2054–2060 (2010)
Zhang, X., He, H., Cao, S., Liu, H.: Flow field texture representation-based motion segmentation for crowd counting. Mach. Vis. Appl. 26(7), 871–883 (2015). https://doi.org/10.1007/s00138-015-0703-0
Zhao, W., Zhang, Z., Huang, K.: Gestalt laws based tracklets analysis for human crowd understanding. Pattern Recognit. (2017). https://doi.org/10.1016/j.patcog.2017.06.020
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Almeida, I., Jung, C. Crowd flow estimation from calibrated cameras. Machine Vision and Applications 32, 7 (2021). https://doi.org/10.1007/s00138-020-01132-y
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DOI: https://doi.org/10.1007/s00138-020-01132-y