A six degrees of freedom, 6DoF, video data processing method performed by a 6DoF video receiving apparatus, the 6DoF video data processing method comprising: receiving metadata of the 6DoF video; decoding pictures of a 6DoF video based on the metadata, and deriving an image corresponding to a viewing position of a user; and rendering the image in a 3D space centered on the viewing position of the user by processing the image based on the metadata, wherein the metadata comprises camera information for a camera capturing the 6DoF video, rotation information about an initial view of the 6DoF video and position information of the initial view of the 6DoF video and stitching information, wherein the decoding of the pictures based on the metadata and the deriving of the image corresponding to a viewing position of the user comprises: deriving stitching target views based on the camera information and the stitching information; deriving pictures of the stitching target views among the decoded pictures; and deriving the image corresponding to a viewing position of the user by stitching the pictures, wherein the camera information comprises camera array information about the 6DoF video, information representing the number of views captured by the camera, and position information of the views, and wherein the stitching information comprises information representing the number of the stitching target views and position information of the stitching target views, characterised such that the metadata further includes re-projection information metadata including: a reserved range type for representing a type of a reserved rendering range for the 6DoF video and a rendering type representing how information of an image is rendered at the reserved rendering position. receiving metadata of the 6DoF video; decoding pictures of a 6DoF video based on the metadata, and deriving an image corresponding to a viewing position of a user; and rendering the image in a 3D space centered on the viewing position of the user by processing the image based on the metadata, wherein the metadata comprises camera information for a camera capturing the 6DoF video, rotation information about an initial view of the 6DoF video and position information of the initial view of the 6DoF video and stitching information, wherein the decoding of the pictures based on the metadata and the deriving of the image corresponding to a viewing position of the user comprises: deriving stitching target views based on the camera information and the stitching information; deriving pictures of the stitching target views among the decoded pictures; and deriving the image corresponding to a viewing position of the user by stitching the pictures, wherein the camera information comprises camera array information about the 6DoF video, information representing the number of views captured by the camera, and position information of the views, and wherein the stitching information comprises information representing the number of the stitching target views and position information of the stitching target views, characterised such that deriving stitching target views based on the camera information and the stitching information; deriving pictures of the stitching target views among the decoded pictures; and deriving the image corresponding to a viewing position of the user by stitching the pictures, wherein the camera information comprises camera array information about the 6DoF video, information representing the number of views captured by the camera, and position information of the views, and wherein the stitching information comprises information representing the number of the stitching target views and position information of the stitching target views, characterised such that