A central decoding controller and a central decoder controlling method are disclosed. A video stream is processed and transmitted via at least two parallel channels. The method comprises steps of: receiving a video key frame obtained by decoding an original video frame via a first channel, and a plurality of intra-description frames neighboring the video key frame; receiving a predictive video frame obtained by processing a prediction analysis and an error correction to the original video frame via a second channel parallel to the first channel; receiving a plurality of inter-description frames via the second channel, the inter-description frames neighboring the video key frame; calculating correlation of the video key frame, the intra-description frames, and the inter-description frames; and selecting the video key frame or the predictive video frame as an output frame according to the correlation result. The method can improve video quality under wireless transmission or unstable internet transmission.