PCK nasal dorsum
The turquoise segment represents the length between the center of the eyes and the tip of the nose, i.e., the nasal dorsum. Any model prediction (represented in green) that falls within this distance of the ground-truth location (indicated in red) is considered as detected. In this case, all keypoints are detected except for the shoulders, neck, left wrist, and the hip (circled in purple). Hence, for this image, the detection rate would be 12/17 = 0.706 = 70.56%.