A power consumption estimation method is applied to an image with N rows of pixels, and comprises a pixel estimation procedure comprising performing an estimation sub-procedure pixel by pixel for each of a plurality of pixels in one row of the N rows of pixels to obtain a plurality of pixel energy consumption values respectively corresponding to the plurality of pixels in said one row of the N rows, and obtaining a row power consumption value corresponding to said one row of the N rows according to the plurality of pixel energy consumption values. The estimation sub-procedure comprises obtaining pixel content information corresponding to one of the plurality of pixels, and determining the pixel energy consumption value according to the pixel content information. The pixel energy consumption value indicates pixel energy consumption generated by performing a predetermined image processing procedure for said one of the plurality of pixels.