An edge area determining apparatus for a still image includes a pixel edge determining part for determining a pixel edge area of a current frame and a pixel edge area of a previous frame in the unit of pixel, a block edge determining part for dividing each of the current frame and the previous frame into a plurality of blocks, each of which comprises a plurality of pixels, and calculating block edge areas in the unit of block based on the pixel edge areas in each of the blocks, and an edge map generating part for generating an edge map based on the calculated block edge areas.