In an image processing apparatus, a still image immediately before a moving image is photographed is divisionally encoded in correspondence to a slice area of the moving image, and a compression table of the slice area in one frame of the moving image is determined based on a compressed data amount of corresponding divisional encoding of the still image. Thus, the image processing apparatus determines the compression table for each slice area of the moving image so that constant compressed data amount for one entire frame of the moving image is attained without performing a trial compression.