Disclosed are computer-implemented methods, non-transitory computer-readable media, and systems for image processing. One computer-implemented method includes determining a rotated angle of an identification (ID) document image, where the rotated angle corresponds to an angle between a bottom edge of the ID document image and an x-axis. The ID document image is rotated based on the rotated angle, where an angle is defined between the bottom edge of the rotated ID document image and the x-axis, and where a value of the angle is within a predefined range. Image regression is performed on the rotated ID document image to obtain coordinates of four corner points of the rotated ID document image. Image alignment is performed on the rotated ID document image based on the coordinates of four corner points of the rotated ID document image.