Selection method for reference frame based on rate-distortion optimization and frame loss prediction

Abstract

The invention discloses a selection method for a reference frame based on rate-distortion optimization and frame loss prediction. The method comprises the following steps of S1, determining a target optimization rate-distortion function through utilization of an aggregate function, wherein the aggregate function is used for comparing a decoded probability of a reconstructed frame with distortion between the reconstructed frame and a current coding frame; S2, multiplying a frame loss probability by prediction of a probability that a sent reference frame is lost, wherein a step size from the sent reference frame to the current coding frame is x, thereby forming a first item of the target optimization rate-distortion function; S3 computing distortion magnitude between certain frame and the current coding frame after the certain frame is taken as reference, wherein certain distance exists between the certain frame and the current coding frame, and multiplying a Lagrange multiplier lambda by the distortion magnitude, thereby forming a second item of the target optimization rate-distortion function; and S4, obtaining the optimum reference frame through search of a step value which enables the target optimization rate-distortion function to be minimum. According to the method, distortion possibly resulting from loss of the selected reference frames can be reduced, and moreover, codingefficiency is also taken into consideration, so user experience is improved.

Description

technical field [0001] The invention belongs to the field of video codec and video stream transmission, in particular to a method for selecting a reference frame based on rate-distortion optimization and frame loss prediction. Background technique [0002] Video communication is a commonly used communication method in modern communication, and it appears in all aspects of our lives, such as webcast, video news, video conferencing, etc. The characteristics of video information are intuitive and informative. For real-time video systems such as live broadcast or video conferencing, how to ensure real-time and efficient transmission of video streams is extremely important. In order to ensure low latency in real-time playback, there are usually only two frame types in this type of video, I and P, and B frames are not used. Existing widely used codec technologies such as H264 or HEVC usually select the previous frame as a reference frame to encode the current frame when performin...

AI Technical Summary

Problems solved by technology

Another method is FEC. FEC provides an effective way to combat packet loss by adding redundant data. Because there is no need for retransmission or reverse channel, this method is often used in real-time or multicast applications. However, if the burst packet loss length exceeds FEC The performance of FEC can be poor when the error correction capability

In addition, redundant packets usually take up more storage space and require greater bandwidth during transmission

ARQ and FEC can reduce the negative impact of network packet loss on video quality, but due to delay and bandwidth limitations, it is still necessary to consider how to further reduce the negative impact of packet loss on video experience in practical applications

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