Allocation method of video image macro-block-level self-adaptive code-rates

Abstract

The invention relates to the field of video image code rate allocation, in particular to an allocation method of video image macro-block-level self-adaptive code-rates. The method conducts analysis and processing by taking a macro-block as a unit, and adopts a bit allocation model which combines bit number of macro-block-level with macro-block energy, thus combing the bit allocation of each macro-block with the macro-block energy. The model can organically combine a code-rate control algorithm with natural characteristics of an image, so that the reconstructed image is closer to the human subjective effect on the premise of not increasing the network bandwidth. By extracting and abstracting macro-block characteristic into the macro-block energy, and closely relating the code-rate allocation to the macro-block energy, the code-rate control accuracy can be provided, the encoding quality is controlled simultaneously, and quality changes of the image in space can be smoothed, thus improving the subjective quality of the image. The method is especially applicable to videos with low code-rate or narrowband, does not rely on specific encoding systems, and can be widely applicable to H.264, MPEG-4 or other encoders.

Description

technical field [0001] The invention relates to the field of video image code rate allocation, in particular to a video image macroblock-level self-adaptive code rate allocation method. Background technique [0002] Rate control is one of the important technologies of video coding, which plays an important role in applications such as video storage and transmission. For video online transmission with limited bit rate, especially low bit rate, bit rate control is particularly important, which will directly determine the quality of video encoding. In existing video coding rate control methods, in order to make the output rate of the encoder more accurate, the rate control is usually accurate to the macroblock level. However, conventional control methods of this type often lead to spatially uneven image quality in the same image while improving control accuracy. Especially in the case of wireless / low bandwidth, this negative effect will be magnified, and the local overquantiz...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to solve the problem that the uneven distribution of quantization parameters and code rates required to encode the current macroblock leads to uneven image quality of macroblocks, and proposes a macroblock-level adaptive code rate allocation method, which ensures accurate code rate allocation At the same time, it solves the problem of uneven quality in the image space to improve the subjective effect

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