Imaging device and light emission amount control method of the same

A light emission amount control method of an imaging device having a light emitting unit for emitting auxiliary light during image taking, comprising:

• a taken image data acquiring step that acquires non-light emission taken image data which is obtained by non-light emission image taking in which image taking is performed in a state where auxiliary light is not emitted from the light emitting unit, and pre-light emission taken image data which is obtained by pre-light emission image taking in which image taking is performed in a state where auxiliary light is emitted from the light emitting unit;
• a brightness difference calculating step that calculates a brightness difference obtained by subtracting the pre-light emission taken image data from the non-light emission taken image data or a brightness difference obtained by subtracting the non-light emission taken image data from the pre-light emission taken image data, for each of segment areas common to the non-light emission taken image data and the pre-light emission taken image data;
• an evaluation value calculating step that calculates an evaluation value of each of the segment areas on the basis of the brightness difference of each of the segment areas;
• a light emission amount determining step that determines a light emission amount of auxiliary light to be emitted from the light emitting unit during primary image taking, on the basis of the evaluation value of each of the segment areas;
• and
• an evaluation value change control step that performs control for changing first evaluation values which are calculated with respect to specific areas which are at least a portion of segment areas around at least one segment area in which a brightness difference calculated by subtracting the non-light emission taken image data from the pre-light emission taken image data is negative or a at least one segment area in which a brightness difference calculated by subtracting the pre-light emission taken image data from the non-light emission taken image data is positive so that the first evaluation values are reduced when each brightness difference is calculated by subtracting the non-light emission taken image data from the pre-light emission taken image data and an absolute value of negative first evaluation values are reduced when each brightness difference is calculated by subtracting the pre-light emission taken image data from the non-light emission taken image data, in a case where the brightness differences of all of the segment areas calculated by the brightness difference calculating step include negative brightness differences and positive brightness differences together.