1. An image coding device which transmits a bit stream containing (i) a texture image and (ii) a depth image, the image coding device comprising: a depth image coding circuit that codes the depth image; a texture image coding circuit that codes the texture image; and a use result information coding circuit that, only in a case where the use result information coding circuit determines that a content of a NAL unit is the texture image, the NAL unit being contained in the bit stream, generates a use result information flag that indicates whether or not a coded depth image is used in coding the texture image and codes the use result information flag thus generated, wherein the use result information coding circuit generates the use result information flag that indicates that a pixel value of the coded depth image is used in coding the texture image in a case where the texture image coding circuit codes the texture image by using the pixel value of the coded depth image.