A system that includes a three-dimensional (3D) camera configured to capture 3D images of a dairy livestock. The system further includes a memory operable to store a thigh gap detection rule set and a processor operably coupled to the 3D camera and the memory. The processor is configured to obtain the 3D image, to identify one or more regions within the 3D image comprising depth values greater than a depth value threshold, and to apply the thigh gap detection rule set to the one or more regions to identify a thigh gap region. The processor is further configured to demarcate an access region within the thigh gap region. The processor is configured to reduce the width of the access region by shifting a first vertical edge and a second vertical edge of the access region and to determine position information for the first vertical edge and the second vertical edge.
