Research On Deblocking Filter For Digital Video Coding

Block-based hybrid coding is the main structure of current and near future video coding.With the increase of the compression ratio, the subjective quality of video images will be regarded greatly.Fortunately, the deblocking filter can reduce blocking artifacts effectively,thus will improve the subject quality significantly.This article introduces the basic theory of deblocking filter and summarizes the basic knowledge of deblocking algorithm in different video coding standard. In order to improve loop filter in H.264 standard, we propose a new algorithm with lumanance mask and texture mask in HVS—A Fast Loop Filter based on HVS(FLF). First we introduce the development of video coding standard, including the H.264 standard as well as its key technologies. Then we analys the relationship of block artifacts and quantization, because it is the quantization that introduce the blocking artifacts. After that we analys two typical algorithms in recent video coding standards—loop filter and post filter, and we make detail compare of each deblocking algorithm. In order to improve the present algorithm in H.264 standard, we raise a mode selection function which contain lumanance mask and texture mask, we use this mode selection function to classify the block bundary of each macroblock, and then use different filter to smooth each type of boundary. The experiment result show that the FLF algorithm can reduce the computation complexity compare to the original algorithm, meanwhile, image blocking artifacts metric shows the FLF algorithm can obtain better deblocking video quality.