The invention provides a method and a device for encoding and decoding videos by aiming at a film source with illumination change. According to the method, the luminance information and the chrominance information of a reference frame are subjected to concurrent correction processing, so that the correlation between the reference frame and an encoding frame is enhanced, and the effects of reducing the number of intra-frame prediction modes of inter-frame prediction frames, reducing the consumption of code rate, and improving the performance of an encoder for eliminating the redundancy of inter-frame information are achieved finally.