1. A computing device, the computing device being connected to an image capturing device, the computing device comprising: a storage system; at least one processor; and one or more programs stored in the storage system and executable by the at least one processor, the one or more programs comprising: an image obtaining module operable to capture an image of the object using the image capturing device, and obtain a standard image of the object from the storage system; a determination module operable to determine a target area that contains most image characteristics of the object from the standard image, extract a standard pixel block having N×N pixels from the target area, divide the captured image into M pixel blocks a 1 , a 2 ,. .. ai,. .. , am, in which a central pixel of the standard pixel block is defined as a standard pixel, and each pixel block ai has N×N pixels; a calculation module operable to calculate an image average energy density (IAED) value of the standard pixel block based on red, green, and blue (RGB) channels and an IAED value of each pixel block ai of the captured image based on the RGB channels, calculate an absolute value of a first difference value between the IAED value of the standard pixel block and the IAED value of each pixel block of the captured image, and create a sequence {S 1 , S 2 ,. .. , Si,. .. , Sm} according to the absolute value; a searching module operable to search for a minimum value Si of the sequence {S 1 , S 2 ,. .. , Si,. .. , Sm}, and determine a pixel block ai corresponding to the minimum value Si as a target pixel block, in which a central pixel of the target pixel block is defined as a target pixel; and a correction module operable to calculate a second difference value between a pixel value of the standard pixel and a pixel value of the target pixel based on the RGB channels, correct a pixel value of each pixel of the captured image according to the second difference value, and output the corrected image to a display device of the computing device for display.