1. An image processing device comprising: a processing degree setting unit that sets a target degree for color processing with regard to at least two properties of a plurality of properties of an image signal, as a single target processing degree; a processing coefficient group creation unit that creates a processing coefficient group for performing color processing of the single target processing degree, based on the single target processing degree set by the processing degree setting unit and a plurality of base coefficient groups that perform the color processing of the single target processing degree to differing degrees, wherein the plurality of base coefficient groups are created in advance; and a color processing execution unit that performs the color processing of the single target processing degree with respect to the image signal using the processing coefficient group created by the processing coefficient group creation unit, wherein the color processing of the single target processing degree is memory color correction, wherein the plurality of base coefficient groups do not change with respect to the image signal, wherein the plurality of base coefficient groups have conversion characteristics such that a point in a color space according to the image signal after the memory color correction is in a predetermined region in the color space, and wherein the processing degree setting unit sets: a default value for the single target processing degree, the default value being a value not at an edge of the predetermined region in the color space; a first boundary value, which is an upper limit value for the single target processing degree; and a secondary boundary value, which is a lower limit value for the single target processing degree, wherein the processing coefficient group creation unit creates: a default processing coefficient group corresponding to the default value; a first processing coefficient group corresponding to the first boundary value; and a second processing coefficient group corresponding to the second boundary value, wherein, in a case when the single target processing degree is a value in a range between the default value of the single target processing degree and the first boundary value, the processing coefficient group creation unit creates the processing coefficient group for performing the memory color correction by interpolating the default processing coefficient group and the first processing coefficient group based on the single target processing degree, and wherein, in a case when the single target processing degree is a value in a range between the default value of the target degree and the second boundary value, the processing coefficient group creation unit creates the processing coefficient group for performing the memory color correction by interpolating the default processing coefficient group and the second processing coefficient group based on the single target processing degree.