Rapid search for spherical objects in aerial photographs
نویسندگان
چکیده
This paper describes a method for detecting and segmenting spherical features using the gradient angle transform. An analysis of the gradient angle for ideal spheres is presented, with a discussion of how this may be used to locate the boundaries of the sphere. The algorithms used by a program which detects and segments spherical features are then presented. The results of applying the program to images with naturally-occurring spherical features are given._ Acknowledgements: This work was supported in part by the Defense Mapping Agency under contract DMA800-85-C-0010. Acceion For NTIS CRA&I DTIC TAB Lii SJu.tfc.t........................... Dist; ibUti-on 4 \ "Ave:ability odes 'Y-" AvA a.,dlor IDistI
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