The Human Pose Estimator model detects humans and their poses in a given image. The model first detects the humans in the input image and then identifies the body parts, including nose, neck, eyes, shoulders, elbows, wrists, hips, knees, and ankles. Next, each pair of associated body parts is connected by a "pose line"; for example, as the following image shows, a line may connect the left eye to the nose, while another may connect the nose to the neck. Each pose line is represented by a list [x1, y1, x2, y2], where the first pair of coordinates (x1, y1) is the start point of the line for one body part, while the second pair of coordinates (x2, y2) is the end point of the line for the other associated body part. The pose lines are assembled into full body poses for each of the humans detected in the image.