1. A method for performing bad pixel compensation, the method comprising: with regard to each direction of a plurality of directions, summing up absolute values of differences between a plurality of sets of first pixel values around a target pixel of an image to generate a first detection value, and with regard to each direction of at least one portion of the directions, summing up absolute values of differences between a plurality of sets of second pixel values around the target pixel to generate a second detection value, wherein each set of the sets of first pixel values and the sets of second pixel values comprises two pixel values corresponding to a difference, two pixel values of a same set belong to a same color channel, each set of first pixel values does not comprise a pixel value of the target pixel, and each set of second pixel values comprises the pixel value of the target pixel; and with regard to a specific direction of the directions, selectively performing bad pixel compensation on the target pixel according to the first detection value and the second detection value.