{"references": ["A. K. Dey, G. D. Abowd, P. J. Brown, N. Davies, M. Smith, and P.\nSteggles. Towards a better understanding of context and\ncontextawareness. In Proceedings of the 1st International Symposium on\nHandheld and Ubiquitous Computing, 1999.", "M. Gro\u00dfmann, M. Bauer, N. Hoenle, U.-P. Kaeppeler, D. Nicklas, and T.\nSchwarz. Efficiently managing context information for large-scale\nscenarios. In Proceedings of the 3rd IEEE International Conference on\nPervasive Computing and Communications, 2005.", "K. Henricksen and J. Indulska. A software engineering framework for\ncontext-aware pervasive computing. In Proceedings of the 2nd IEEE\nInternational Conference on Pervasive Computing and Communications,\n2004.", "M. Roman and R. H. Campbell. Gaia: Enabling active spaces. In\nProceedings of the 9th ACM SIGOPS European Workshop, Kolding,\n2000.", "D. Salber, A., K. Dey, and G. D. Abowd. The Context Toolkit: Aiding\nthe development of context-enabled applications. In Proceedings of the\nSIGCHI Conference on Human Factors in Computing Systems: The CHI\nis the Limit, 1999.", "A. Blessing, A.; S. Klatt, D. Nicklas, S. Volz, and H. Schuetze.\nLanguage-Derived Information and Context Models. In Proceedings of\nthe 3rd Workshop on Context Modelling and Reasoning at 4th IEEE\nInternational Conference on Pervasive Computing and Communication\nperCom, 2006.", "U.-P. Kaeppeler, R. Benkmann, O. Zweigle, R. Lafrenz, P. Levi:\nResolving Inconsistencies in Shared Context Models using Multiagent\nSystems. In R. Dillmann and W. Burgard (eds.): Proceedings of the 10th\nInternational Conference on Intelligent Autonomous Systems: IAS-10;\nBaden Baden, Germany, July 23-25, 2008.", "M. Bauer, L. Jendoubi, and O. Siemoneit. Smart Factory - Mobile\nComputing in Production Environments. In Proceedings of the MobiSys\nWorkshop on Applications of Mobile Embedded Systems WAMES,\n2004.", "L. M. Hilty, C. Som, and A. Koehler. Impacts of Future Information and\nCommunication Technologies on Society and Environment. In G. Banse,\nI. Hronszky, and G. Nelson (eds.): Rationality in an uncertain world.\nedition sigma, 2005, 205-290.\n[10] M. Bauer, C. Becker, J. Haehner, and G. Schiele. ContextCube -\nProviding context information ubiquitously. In Proceedings of the 3rd\nInternational Workshop on Smart Appliances and Wearable Computing,\n2003.\n[11] U.-P. Kaeppeler, A. Gerhardt, C. Schieberle, M. Wiselka, K.\nHaeussermann, O. Zweigle, and P. Levi. Reliable situation recognition\nbased on noise levels. In Proceedings of the 1st International Conference\non Disaster Management and Human Health Risk, 2009. (Forthcoming)\n[12] D. G. Lowe. Distinctive image features from scale-invariant keypoints.\nInternational Journal of Computer Vision, 60:91-110, 2004.\n[13] P. Viola and M. Jones. Rapid object detection using a boosted cascade of\nsimple features. pages 511-518, 2001.\n[14] H. Bay, A. Ess, T. Tuytelaars, and L. van Gool. Speeded-up robust\nfeatures (surf) ). Computer Vision and Image Understanding, 110(3):346\n- 359, 2008. Similarity Matching in Computer Vision and Multimedia.\n[15] J.Kittler, M. Hatef, R. P.W. Duin, and J. Matas. On combining\nclassifiers. IEEE Transactions on Pattern Analysis and Machine\nIntelligence, 20(3):226-239, 1998.\n[16] Z. Stejic, Y. Takama, and K. Hirota. Mathematical aggregation operators\nin image retrieval: effect on retrieval performance and role in relevance\nfeedback. Signal Processing, 85(2):297 - 324, 2005. SI on Content\nBased Image and Video Retrieval.\n[17] M. Varma and D. Ray. Learning the discriminative power-invariance\ntrade-off. In Computer Vision, 2007. ICCV 2007. IEEE 11th\nInternational Conference on, pages 1-8, Oct. 2007.\n[18] O. R. Terrades, E. Valveny, and S.Tabbone. Optimal classifier fusion in\na non-bayesian probabilistic framework. IEEE Trans. Pattern Anal.\nMach. Intell., 31(9):1630-1644, 2009.\n[19] A. Opelt, A. Pinz, M. Fussenegger, and P. Auer. Generic object\nrecognition with boosting. Pattern Analysis and Machine Intelligence,\nIEEE Transactions on, 28(3):416-431, March 2006.\n[20] B.C. Russell, A. Torralba, K.P. Murphy, and W.T. Freeman. LabelMe: A\nDatabase and Web-based Tool for Image Annotation. Int. J. Comput.\nVision, 77(1-3):157-173, 2008.\n[21] L. von Ahn and L. Dabbish. Labeling images with a computer game. In\nHuman factors in computing systems. CHI 04. SIGHI conference on.\nPages 319-326, 2004.\n[22] S. Ayache and G. Quenot. Trecvid 2007 collaborative annotation using\nactive learning. In In Proceedings of the TRECVID 2007 Workshop,\n2007.\n[23] G. Heidemann, A. Saalbach, and H. Ritter. Semi-automatic acquisition\nand labeling of image data using SOMs. In ESANN, pages 503-508,\n2003.\n[24] H. Bekel, G. Heidemann, and H. Ritter. Interactive image data labeling\nusing self-organizing maps in an augmented reality scenario. Neural\nNetw., 18(5-6):566-574, 2005.\n[25] T. Schreck, J. Bernard, T. von Landesberger, and J. Kohlhammer. Visual\ncluster analysis of trajectory data with interactive kohonen maps.\nInformation Visualization, 8(1):14-29.\n[26] D. Lucke, E. Westkaemper, M. Eissele, T. Ertl, O. Siemoneit, and C.\nHubig. Privacy-Preserving Self-Localization Techniques in Next\nGeneration Manufacturing. An Interdisciplinary View on the Vision and\nImplementation of Smart Factories. In Proceeding of the 10th\nInternational Conference on Control, Automation, Robotics and Vision\nICARCV, 2008.\n[27] M. Wieland,C. Laengerer, F. Leymann, O. Siemoneit, and C. Hubig.\nMethods for Conserving Privacy in Workflow Controlled Smart\nEnvironments. A Technical and Philosophical Enquiry into Human-\nOriented System Design of Ubiquitous Work Environments. In\nProceedings of the 3rd International Conference on Mobile Ubiquitous\nComputing, Systems, Services and Technologies Ubicomm, 2009.\n(Forthcoming)\n[28] F. Porikli. Trajectory distance metric using hidden markov model based\nrepresentation. In Proceedings of the 8th IEEE European Conference on\nComputer Vision, PETS Workshop, 2004.\n[29] Unabhaengiges Landeszentrum fuer Datenschutz Schleswig-Holstein.\nVideoueberwachung und Webkameras (German). Blaue Reihe Vol. 4.\nURL=https://www.datenschutzzentrum.de/blauereihe/blauereihevideo.\npdf\n[30] M. Lang. Private Videoueberwachung im oeffentlichen Raum. Eine\nUntersuchung der Zulaessigkeit des privaten Einsatzes von Videotechnik\nund der Notwendigkeit von \u252c\u00ba 6b BDSG als spezielle rechtliche Regelung\n(German). Hamburg, 2008.\n[31] A. Rossnagel, S. Jandt, J. Mueller, A. Gutscher, and J. Heesen.\nDatenschutzfragen mobiler kontextbezogener Systeme (German).\nWiesbaden, 2006.\n[32] O. Siemoneit, C. Hubig, M. Kada, M. Peter, and D. Fritsch. Google\nStreet View and Privacy. Some thoughts from a philosophical and\nengineering point of view. In Proceedings of the 5th Asiac-Pacific\nConference on Computing and Philosophy, 2009.\n[33] M. Kada, M. Peter, D. Fritsch, O. Siemoneit, and C. Hubig. Privacy-\nEnabling Abstraction and Obfuscation Techniques for 3D City Models.\nIn Proceeding of the 2nd SIGSPATIAL ACM GIS International\nWorkshop on Security and Privacy in GIS and LBS, 2009.\n(Forthcoming)"]}

Image data holds a large amount of different context information. However, as of today, these resources remain largely untouched. It is thus the aim of this paper to present a basic technical framework which allows for a quick and easy exploitation of context information from image data especially by non-expert users. Furthermore, the proposed framework is discussed in detail concerning important social and ethical issues which demand special requirements in system design. Finally, a first sensor prototype is presented which meets the identified requirements. Additionally, necessary implications for the software and hardware design of the system are discussed, rendering a sensor system which could be regarded as a good, acceptable and justifiable technical and thereby enabling the extraction of context information from image data.