Patent ID: 9046935
Filing Date: 2015-06-02
Classification: G06F,G06K,Y02D

Abstract:
1. A power saving method for a motion estimation device, the motion estimation device having a fixed sampling period and comprising a light source illuminating with an adjustable emitting cycle to provide the needed light for the motion estimation device during capturing images, the power saving method comprising: calculating a first differential image at a first time; calculating a second differential image at a second time, wherein a time interval between the first time and the second time is equal to one emitting cycle and the emitting cycle is a first integral multiple of the fixed sampling period; comparing the first differential image and the second differential image to obtain a displacement between the first differential image and the second differential image; comparing the displacement with at least one threshold value; and adjusting the emitting cycle of the light source to a second integral multiple of the fixed sampling period according to a comparison result of comparing the displacement and the threshold value and maintaining the fixed sampling period unchanged when adjusting the emitting cycle of the light source, wherein the emitting cycle is longer than the fixed sampling period; wherein the first differential image and the second differential image are obtained by subtracting a background image captured when the light source is turned off from an effective image captured when the light source is illuminating, and the effective image and the background image are captured within the same emitting cycle.