In an image processing device, a processor is configured to perform: (a) acquiring target image data representing an image including a plurality of pixels, where the target image data includes a plurality of sets of pixel data corresponding to the plurality of pixels, where the image includes an object having at least one pixel of the plurality of pixels; (b) detecting the object in the image based on the target image data; (c) determining characteristic data indicating a potential for an occurrence of banding in the object based on the target image data; (d) determining a parameter based on the characteristic data; and (e) executing a halftone process to determine, for each of the plurality of pixels, a dot to be found based on the corresponding set of pixel data by using the parameter.