Video image high-quality transcoding method with excellent error code resistance

Abstract

The invention provides a video image high-quality transcoding method with excellent error code resistance. According to the video image high-quality transcoding method, a fragmentation adaptive transcoding algorithm is provided for optimizing distortion-limited information source coding at a video image transcoding end, the fragmentation adaptive transcoding algorithm is based on a fragmentation technology of MPEG-4 advanced video coding, combines a distortion limiting information source coding theory, establishes a uniform fragmentation number limit distortion information source coding model,and adopts a strategy of adaptively adjusting the fragment number of each frame of image to consider the code rate and the fault-tolerant performance; and at a video image decoding end, a space-timerelated rapid stepping error masking correction algorithm is provided, on the basis of a rapid stepping image error recovery method, the space-time related rapid stepping error masking correction algorithm is used for correcting a video residual error, and recovers a whole macro block in combination with time domain information of a video image. Experimental results show that the two fault-tolerant algorithms can effectively enhance the fault-tolerant performance of the video image.

Description

technical field [0001] The invention relates to a high-quality video image transcoding method, in particular to a video image high-quality transcoding method with excellent anti-error performance, and belongs to the technical field of video image transcoding. Background technique [0002] Since the 1990s, with the rapid development of mobile communication technology, computer technology and Internet technology, a large number of media industries under the support system of new technologies have been born, and the amount of multimedia information and data has shown explosive growth. In this context, people's life, work and study are increasingly closely related to the multimedia industry. For video image information, the amount of information is huge and there is much redundant information. The purpose of video image coding is to compress the video image information as much as possible. With the development of video image coding technology, various video coding standards hav...

AI Technical Summary

Problems solved by technology

However, the above-mentioned fault-tolerant methods in the prior art are not optimized for distortion-limited source coding. When the embedding of the fault-tolerant algorithm brings the problem of code rate increase, it is impossible to achieve a good balance between code rate and distortion.

[0005] In terms of the optimization model of distortion-limited source coding in the prior art, an idea was proposed at the beginning of this century, which decomposes the error-tolerant insertion of distortion-limited source coding into two sub-problems: the optimization of macroblock mode selection and the optimization of resynchronization mark insertion , so that the signal-to-noise ratio can be improved by 1.3 to 2.3dB, but this method does not consider the error diffusion characteristics of the Inter frame

Almost at the same time, a distortion-limited source coding model based on a statistical model appeared, which expresses the error diffusion characteristics of the video bit stream and can be used to calculate the optimal bit allocation between source coding and error-tolerant coding, but This approach does not take into account the impact of false occlusion corrections

Afterwards, redundant motion vectors are inserted into the video stream in video transcoding, so that the decoder can use the redundant motion vectors to restore the damaged or lost macroblock motion vectors, and improve the performance of error concealment correction at the decoding end. Insertion will also lead to an increase in the code rate, but this algorithm must require the decoding end to have the ability to decode redundant motion vectors

[0006] On the whole, the defects of the video image transcoding method in the prior art are mainly manifested in the following aspects: First, once the video code stream in the prior art is compressed, it is subject to the characteristics of high delay, low bandwidth, and high bit error of the channel , it will inevitably lead to bit error problems in the video transmission process, resulting in the spread of error codes, especially for wireless networks, the bit error rate is higher, and the existing technology lacks effective solutions; Adding error-tolerant information in the code stream to improve the robustness of the code stream, there is no error recovery performance, it is impossible to overcome the error propagation, and the robustness of the compressed code stream is very poor; the third is that the fault-tolerant methods in the prior art are not optimal distortion-limited source coding Yes, when the embedding of the error-tolerant algorithm brings the problem of code rate increase, it is impossible to achieve a good balance between the code rate and distortion; Fourth, the prior art distortion-limited source coding optimization model does not consider the error diffusion characteristics of the Inter frame, The influence of error masking correction is not considered, and the decoding end must be required to have the ability to decode redundant motion vectors. There are various major constraints, and there are many difficulties in the use process, and the quality of image transcoding is not high.

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