请高手翻译下,英译中（机器绕走）

请高手翻译下,英译中（机器绕走）
A. Shape features--the elongation measure and trunk orientation of each swimmer arc extracted by fitting the swimmer segmentation result with a best-fit ellipse (see Figure 2) [6]. The elongation measure of the ellipse, which is defined as the ratio between the lengths of the major and minor axes, is used to characterize the swimmer's body posture, namely being nearly vertical in the water or being almost parallel to the water surface.
The orientation of the ellipse is used to approximate the orientation of the swimmer's trunk.
B. Motion feature--as the overhead camera used in our system is mounted high above the pool to minimize the perspective foreshortening effects, the moving speed of a swimmer can be approximated by the inter-frame displacement of his/her ellipse's centroid. To account for imperfect segmentation, the average of the swimmer's centroids over a few consecutive frames is used.
小提示
A特征提取
B行动提取
机器翻的不通 谢谢