An image reading apparatus, comprising: an acquisition section configured to acquire a plurality of first images obtained by successively reading portions of an object which is swept on a sensor of the acquisition section along one direction; an extrapolation section configured to extrapolate the plurality of first images to generate a respective plurality of second images obtained by extending the image areas of the plurality of first images; a calculation section configured to calculate a position at which corresponding portions in t images, which are first images acquired at time t or second images corresponding to the first images acquired at time t, and t+Δt images, which are first images acquired at time t+Δt or second images corresponding to the first images acquired at time t+Δt, overlap with each other, as a relative position of the t+Δt images with respect to the t images; and an instruction section configured to repeatedly, until the object remains stationary and at least one state selected from contact range, area, average movement speed, variation in movement speed, movement direction and variation in movement direction of the object with respect to the sensor satisfies a predetermined condition: predict, based on the relative position of the t images with respect to t-Δt images, which are first images acquired at time t-Δt or second images that correspond to the first images acquired at time t-Δt and that have previously been calculated by the calculation section, the relative position of the t+Δt images with respect to the t images before the first images are acquired at the time t+Δt by the acquisition section, determine, after the first images are acquired at time t+Δt by the acquisition section, to perform extrapolation processing with respect to the first images acquired at time t+Δt when there is no overlap between the t images and the first images acquired at time t+Δt and when it is determined to perform extrapolation processing, issue an instruction to the extrapolation section to extrapolate the first images acquired at time t+Δt to generate a respective plurality of second images. an acquisition section configured to acquire a plurality of first images obtained by successively reading portions of an object which is swept on a sensor of the acquisition section along one direction; an extrapolation section configured to extrapolate the plurality of first images to generate a respective plurality of second images obtained by extending the image areas of the plurality of first images; a calculation section configured to calculate a position at which corresponding portions in t images, which are first images acquired at time t or second images corresponding to the first images acquired at time t, and t+Δt images, which are first images acquired at time t+Δt or second images corresponding to the first images acquired at time t+Δt, overlap with each other, as a relative position of the t+Δt images with respect to the t images; and an instruction section configured to repeatedly, until the object remains stationary and at least one state selected from contact range, area, average movement speed, variation in movement speed, movement direction and variation in movement direction of the object with respect to the sensor satisfies a predetermined condition: predict, based on the relative position of the t images with respect to t-Δt images, which are first images acquired at time t-Δt or second images that correspond to the first images acquired at time t-Δt and that have previously been calculated by the calculation section, the relative position of the t+Δt images with respect to the t images before the first images are acquired at the time t+Δt by the acquisition section, determine, after the first images are acquired at time t+Δt by the acquisition section, to perform extrapolation processing with respect to the first images acquired at time t+Δt when there is no overlap between the t images and the first images acquired at time t+Δt and when it is determined to perform extrapolation processing, issue an instruction to the extrapolation section to extrapolate the first images acquired at time t+Δt to generate a respective plurality of second images. predict, based on the relative position of the t images with respect to t-Δt images, which are first images acquired at time t-Δt or second images that correspond to the first images acquired at time t-Δt and that have previously been calculated by the calculation section, the relative position of the t+Δt images with respect to the t images before the first images are acquired at the time t+Δt by the acquisition section, determine, after the first images are acquired at time t+Δt by the acquisition section, to perform extrapolation processing with respect to the first images acquired at time t+Δt when there is no overlap between the t images and the first images acquired at time t+Δt and when it is determined to perform extrapolation processing, issue an instruction to the extrapolation section to extrapolate the first images acquired at time t+Δt to generate a respective plurality of second images.