An image processing apparatus includes a separating unit that separates image data into foreground image data, background image data, and mask image data; a resolution converting unit that converts the foreground image data into low-resolution foreground image data; a dividing unit that divides the low-resolution foreground image data into a plurality of square blocks composed of a plurality of pixels; an averaging unit that calculates an average pixel value of the pixels included in each of the square blocks, and changes pixel values of the pixels in the square blocks to the average pixel value of that square block thereby obtaining averaged foreground image data of the square blocks; a compressing unit that performs a compression process on the averaged foreground image data of the square blocks thereby obtaining compressed foreground image data of the square blocks.