Patent ID: 8576905

Claim:
A central decoder controlling method, in which 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 between the neighboring inter-description frames, correlation between the video key frame and the neighboring inter-description frames, and correlation between the video key frame and the neighboring intra-description frames; and selecting the video key frame or the predictive video frame as an output frame according to the correlation results; wherein the video key frame is selected as the output frame if a condition (Δ − 12 +Δ + 12 )<(Δ − 2 +Δ + 2 ) is satisfied, where (Δ − 12 +Δ − 12 ) is the sum of the differences between the video key frame and the neighboring inter-description frames, and (Δ − 2 +Δ + 2 ) is the sum of the differences between the video key frame and the neighboring intra-description frames.