Algorithm 1 Standing-pigs detection algorithm

Input: Depth Image Output: Detected Image Step 1: While moving noise remaining Apply spatiotemporal interpolation; Subtract $I_{background}$ with $I_{interpolate}$; Step 2: If widths of undefined values $\le$ 2: Determine as an outline; Else: Determine as a noise and remove it on the area; Step 3: If threshold1 $\le$ subtracted pixel value $\le$ threshold2: Determine as candidates for standing-pigs; Else: Determine as a noise and remove it on the area; Detect edges of candidates; Step 4: Overlap $I_{edge}$ into $I_{outline}$; If outline and edge on the same area:  Determine as an outline; Else:  Determine as a noise and remove it on the area; Step 5: Merge $I_{overlap}$ with $I_{candidate}$; If candidate pigs touch outlines: Detect standing-pigs; Else: Determine as a noise and remove it on the area;