Image forming apparatus, image forming method, and computer readable recording medium for recording program that determines a fixing portion target temperature based on presence or absence of an image with a specific characteristic

Abstract

An image forming apparatus includes a first determining portion for determining the presence of a first image with at least a first number of pixels having a density-related value of at least a predetermined value continuously arrayed in a subscanning direction, and with at least a second, greater, number of pixels having the density-related value of at least the predetermined value continuously arrayed in a main scanning direction. It also includes a second determining portion for determining a target temperature at which to maintain a fixing portion based on the presence of the first image, when a determination result indicates the presence of the first image, or based on a density-related value of a second image different from the first image, when the determination result indicates the absence of the first image. The apparatus controls power to the fixing portion to maintain its temperature at the determined target temperature.