Method for auto-depicting trends in object contours

A method for auto-depicting trends in object contours, comprising:

• (a) receiving an input image;
• (b) extracting a plurality of coordinates and a plurality of angular values of image edges;
• (c) selecting a start point from the coordinates of the image edges;
• (d) defining a region of the input image as a first region, wherein the first region comprises the start point;
• (e) based upon a plurality of angular values corresponding to the first region to obtain a main angular value, determining a first angular value screening range based on the main angular value, and performing angular value screening upon the first region based on the first angular value screening range to obtain a first significant angular value and a first index;
• (f) determining a probe point on the input image in accordance with the first significant angular value obtained in step (e), defining a second region comprising the probe point, determining a second angular value screening range in accordance with the first significant angular value, and performing angular value screening upon the second region in accordance with the second angular value screening range to obtain a second significant angular value and a second index, wherein the second angular value screening range is greater than the first angular value screening range;
• (g) utilizing the second significant angular value to update the first angular value screening range, and performing angular value screening upon the first region to update the first significant angular value;
• (h) determining a new start point in accordance with the first significant angular value obtained in step (g), and replacing the start point of step (d) with the new start point;
• and
• (i) repeating steps (d) to (h) until the first index or the second index is lower than a threshold.