\ccRefPageBegin \begin{ccRefConcept}{LabeledImage_3} \ccDefinition The concept \ccRefName\ describes the requirements for the second template parameter of the class \ccc{Labeled_image_mesh_domain_3} which represents mesh domains defined by 3D labeled images. A 3D labeled image is a 3D array of elements of an integral type~\ccc{Type}. \ccc{Type} can be \ccc{bool}, \ccc{char}, \ccc{short}, \ccc{int}, or \ccc{long} (signed or not). Such an array is associated to a 3D axis-aligned regular grid, in $\mathbb{R}^3$. A cell of this grid is denoted by \textit{voxel}. A voxel is an iso-cuboid of size \ccc{vx()}, \ccc{vy()}, and \ccc{vz()}. \ccTypes \ccNestedType{Type}{Type of voxel data. Must be an integral type.} \ccNestedType{RT}{Ring number type.} \ccCreationVariable{image} \ccOperations \ccMethod{int xdim();}{First dimension of the 3D array, i.e., the number of voxels along the x coordinate axis.} \ccMethod{int ydim();}{Second dimension of the 3D array.} \ccMethod{int zdim();}{Third dimension of the 3D array.} \ccMethod{RT vx();}{Size of each voxel along x coordinate axis.} \ccMethod{RT vy();}{Size of each voxel along y coordinate axis.} \ccMethod{RT vz();}{Size of each voxel along z coordinate axis.} \ccMethod{const Type* data();}{Pointer to the first element of the 3D image. The size of the array must be \ccc{xdim()}$\times$\ccc{ydim()}$\times$\ccc{zdim()}.} \ccHasModels \ccc{CGAL::Image_3}, for any \cgal{} kernel \ccc{K} and any integral type \ccc{T}. \end{ccRefConcept} \ccRefPageEnd