1. An image decoding device, the device comprising: prediction parameter derivation circuitry that derives a prediction parameter of a target image; and a predicted image generator that generates a prediction image based on the prediction parameter of the target image, wherein the prediction parameter derivation circuitry performs a first shift operation for coordinates of a reference image, in a case that the target image and the reference image belong to different layers, the prediction parameter derivation circuitry performs a second shift operation for coordinates of a reference image, in a case of performing a temporal prediction, the shift value of the first shift operation differs from the shift value of the second shift operation, and an image generated by the prediction image is displayed on a display device.