This disclosure describes techniques for coding 3D video block units. In one example, a video encoder is configured to receive one or more texture components from at least a portion of an image representing a view of three dimensional video data, receive a depth map component for at least the portion of the image, code a block unit indicative of pixels of the one or more texture components for a portion of the image and the depth map component. The coding comprises coding the depth map component relative to at least one of the texture components, and signalling an attribute of the depth map component relative to the one or more texture components.