1. An image processing apparatus comprising: circuitry configured to warp, between an image of a first viewpoint and an image of a second viewpoint different from the first viewpoint, a picture of the image of the first viewpoint to generate a picture of an warped image obtained by converting the picture of the image of the first viewpoint into an image obtainable in the second viewpoint; acquire a reference index indicating a reference picture to be referred to generate a predicted image of an object block to be decoded of a picture of the image of the second viewpoint; and select the reference picture from reference picture candidates including at least the picture of the warped image based on the reference index.