A self-adapted code rate control method based on relevancy

Abstract

The invention relates to a relevant self-adaptive bit rate control method based on H.264 / AVC. A data quantity used for forecasting a model parameter is self-adaptively adjusted by utilizing the relevance between video frames or macro blocks in the method to ensure that the average data quantity of the model computation is decreased, thereby the computation complexity is decreased. The combination of the frame layer control and the macro block layer control is adopted in the bit rate control method, the variation range of the quantification grade of the macro block in the video frame is contracted, a new MAD model is established on the frame layer, and the weighting solution is operated by adopting the relevance during the process of the model solution and the RD solution; a new MAD forecasting model is established on the macro block layer. According to the correlated characteristic of a space time between the macro blocks, the solution proposal of the MAD model and the RD model is designed. The testing indicates that compared with the G012 standard algorithm, the invention has the advantages that the complexity of the algorithm is low, the bit rate control precision is improved, a buffering area is smoothed, and the PSNR value of the coding video is improved averagely by 0.4dB.

Description

technical field [0001] The invention relates to the field of code rate control in video compression, in particular to an adaptive new code rate control method based on correlation. technical background [0002] H.264 is the latest international standard for video compression developed and researched by the Joint Video Team (JVT) in recent years. This standard provides technical support for video technologies in broadcasting, storage devices, conversational services, and wireless networks. Compared with previous standards, such as: H.263, H.263+, H.263++ and MPEG- 4. The video coding efficiency has been greatly improved. Under the same video quality, H.264 not only saves 50% bit rate than H.263 and MPEG-4, but also has better support for network transmission. With the development of communication and video technology, the transmission of video signals is subject to more and more resource constraints. For video compression and communication, the main limitation lies in the li...

AI Technical Summary

Problems solved by technology

However, in the G012 standard, these situations are not distinguished in detail, which is one of the main reasons why the accuracy of the rate control model is not enough, and it needs to use more data for calculation. In the JM8.6 version, 20 sets of data are required in the front, although The large amount of data used can maintain the accuracy of bit rate control to a certain extent, but when the video sequence undergoes drastic changes or scene switching, it is difficult for the parameters in the model to keep up with the changes, making it difficult for the quantization level to keep up with other Variety

At this time, using too much outdated data for model calculation will cause a decline in model accuracy.

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