Parameter-adaptive multidimensional bit rate control method based on video content characteristics

Abstract

The invention relates to the field of video decoding, in particular to a parameter-adaptive multidimensional bit rate control method based on video content characteristics. The method comprises the following steps: determining an initial coding frame rate according to a channel bandwidth and an initial frame complexity of a video sequence; determining a model parameter update cycle according to a dynamically transformed video, and extracting a video time-space complexity from a sliding window of the current update cycle; meanwhile, determining the length of the next update cycle by combining the bit rate control accuracy of the current update cycle, and updating the multidimensional bit rate control model parameters and the coding parameters. The parameter-adaptive multidimensional bit rate control method based on video content characteristics is superior to internationally similar relevant methods, can effectively improve the subjective quality and objective quality, especially for the video sequence with high time-space complexity, and can slightly reduce the computational complexity.

Description

technical field [0001] The present invention relates to the field of video decoding, in particular to a code rate control method in the field of video coding technology, especially a parameter adaptive multi-dimensional code rate control method based on video content characteristics, which can be applied to multiple integrated heterogeneous networks with large bandwidth A multi-dimensional code rate control method for a network video encoder when the range changes dynamically. Background technique [0002] With the development of multimedia communication and network technology, people's demand for video applications is becoming more and more extensive, and video information is playing an increasingly important role in people's lifestyles and social development; video coding and compression technology is the key to video storage, transmission It is the core technology of applications such as digital TV, video surveillance, and network video; bit rate control technology is one...

AI Technical Summary

Problems solved by technology

[0003] The existing code rate control methods are all based on the adjustment of quantization parameters to balance the code stream, and the existing methods generally can only provide one quality level of video output. This method is not flexible enough for applications with large bandwidth fluctuations, and cannot be used in The comprehensive video quality is optimal under the condition of real-time bandwidth and low bit rate; multi-dimensional bit rate control is proposed under this background, multi-dimensional bit rate control will organically combine the basic means of bit rate adjustment, and will traditional bit rate conversion (change Quantization step size), spatial resolution (video space size), time resolution (frame rate) and other bit rate adjustment methods are combined to complete the adaptive adjustment of the video stream; because the multi-dimensional bit rate control determines the size of each dimension depends on Depending on the code rate for a period of time, it does not need to be divided into several levels in practical applications, which can effectively solve the problems of SVC computational complexity and high redundancy

[0004] But at present, multi-dimensional bit rate control technology is still in its infancy, and more expansive research needs to be carried out. The research on its key technologies has important practical significance for the development of the video industry; at present, multi-dimensional bit rate control methods exist The following problems: (1) The current mainstream methods, such as Q-R-TQ, etc., are based on the entire video information or a fixed period when calculating video content information, but in practical applications, the video content is time-varying. The accuracy of the model coefficients obtained by the sequence is not high, which is not conducive to real-time transmission; (2) The selection of the initial frame rate plays an important role in the multi-dimensional code rate control; if the selected initial frame rate is too large, only the encoding after the initial frame The actual number of bits consumed will exceed the pre-allocated target number of bits, so that the number of bits left for subsequent encoded frames will be very small, which will reduce the quality of the reconstructed video image; on the contrary, choosing too small initial parameters will not only reduce the image quality Decrease, and it will cause a waste of bandwidth resources; delay a few frames to approach real-time communication without affecting the vision, but currently there are almost no relevant methods to pay attention to the selection of the initial frame rate from the perspective of real-time transmission

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