A video encoding decoding method and device and a video codec are provided. The video encoding method includes the following steps. A first view picture is basic-layer encoded as a reference view picture, prediction information is extracted in combination with a second view picture, and the second view picture is re-created. A residual value is calculated according to a re-created second view picture and the original second view picture. When the residual value is greater than a threshold, both the residual value and the prediction information are enhanced-layer encoded simultaneously; otherwise, only the prediction information is enhanced-layer encoded. Encoded information is obtained by multiplexing the enhanced-layer encoding with the basic-layer encoding of the first video picture. The video decoding method includes the following steps. After de-multiplex, basic-layer encoded information and enhanced-layer encoded information are decoded respectively to obtain a first view picture, prediction information, and a residual value, and then a second view picture is re-created. The embodiments of the invention can realize the effective compression of stereo video data, reduce an encoding complexity, and are compatible with the conventional two dimensional displaying, so as to correctly and easily re-create a stereo view picture.