A three-dimensional (3D) video reconstruction method, an encoder and a decoder are provided, comprising obtaining a list of video content screens or video content frames of an object from the 3D video; obtaining a list of depth screens of the 3D video; adding a shape screen to each video frame of the 3D video; superimposing each of the video content screens or video content frames with the depth screen and the shape screen to form a shape identification library; and storing the shape identification library at a header of a compressed file for unmasking of the object. The shape recognition list format may significantly reduce the storage size and increase the compression ratio by replacing the original shape with the identifications, and help improve the rendering quality.