1. A grayscale character dictionary generation apparatus, comprising: a 1st synthetic grayscale degraded character image generation unit for generating a plurality of 1st synthetic grayscale degraded character images using binary character images inputted therein; a clustering unit for dividing each category of the 1st synthetic grayscale degraded character images generated by the 1 st synthetic grayscale degraded character image generation unit into a plurality of clusters; a template calculation unit for generating template for each of the clusters; a transformation matrix generation unit for generating transformation matrix in relation to each of the templates; a 2nd synthetic grayscale degraded character dictionary generation unit for obtaining character feature of every grayscale degraded character of each of the clusters using the transformation matrix, and for constructing eigenspace of each category of the synthetic grayscale degraded character, which is the 2nd synthetic grayscale character dictionary.