1. An image processing apparatus comprising: a first acquisition unit configured to acquire a weighting coefficient sequence including weighting coefficients by which respective captured image data captured by an image capturing device are to be multiplied, the weighting coefficient sequence including at least a ternary weighting coefficient; an input unit configured to input the plurality of captured image data captured by the image capturing device; a second acquisition unit configured to acquire a motion vector from an image represented by the captured image data when acquiring the plurality of captured image data; a synthesis unit configured to multiply the respective captured image data by corresponding weighting coefficients of the weighting coefficient sequence, and synthesize the respective captured image data multiplied by the weighting coefficients, acquiring synthesized image data; and a correction unit configured to correct the synthesized image data based on the motion vector and the weighting coefficient sequence, acquiring corrected image data.