When {HEAD ~ the evaluation value} has changed by {TAIL ~ an amount} exceeding a predetermined threshold value, the distance information calculation and three dimensional processing on the plurality of images and object are performed 
changed by
When { HEAD ~ the evaluation value } has changed by { TAIL ~ an amount } exceeding a predetermined threshold value , the distance information calculation and three dimensional processing on the plurality of images and object are performed
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH