1. A printing device that selects and prints candidate image data from among multiple sets of image data, comprising: a data acquiring unit that acquires one set of image data from among multiple sets of image data, the image data including a plurality of coefficients representing a pattern of change of color of an image along a prescribed direction, the plurality of coefficients corresponding respectively to different frequency component; a basic pattern memory that stores a multiple sets of basic pattern data that respectively include a plurality of basic coefficients representing a pattern of change of color, the plurality of basic coefficients corresponding respectively to different frequency components, each of the multiple sets of basic pattern data including data representing a basic blur level that represents blur level in color boundary areas; a basic pattern selecting unit that selects one set of selected basic pattern data from among the multiple sets of basic pattern data, on the basis of comparison of the plurality of coefficients included in the acquired image data, with the plurality of basic coefficients respectively included in the multiple sets of basic pattern data stored in the basic pattern memory; a candidate determining unit that calculates blur level of the image data on the basis of the basic blur level associated with the selected basic pattern data, and determining on the basis of the blur level whether to designate the acquired image data as a candidate; and a printing unit that prints image data selected as the candidate.