The Causation and Solution of Ringing Effect in DCT-based Video Coding
نویسندگان
چکیده
Ringing effect is one of the most annoying visual artifacts in digital video. It is a significant factor of subjective quality deterioration. However, there is a widely-accepted misunderstanding of its cause. In this paper, we propose a reasonable interpretation of the cause of ringing effect. Based on the interpretation, we suggest further two methods to reduce ringing effect in DCT-based video coding. The methods adaptively adjust quantizers according to video features. Our experiments proved that the methods could efficiently improve subjective quality with acceptable additional computing costs. Keywords—ringing effect, video coding, subjective quality, DCT.
منابع مشابه
A survey of hybrid MC/DPCM/DCT video coding distortions
The motion-compensated hybrid DCT/DPCM algorithm has been successfully adopted in various video coding standards, such as H.261, H.263, MPEG-1 and MPEG-2. However, its robustness is challenged in the face of an inadequate bit allocation, either globally for the whole video sequence, or locally as a result of an inappropriate distribution of the available bits. In either of these situations, the...
متن کاملMorphological Segmentation Based Video Coding Employing Conditional Smoothing
In the context of coding the displaced frame difference signal, morphological segmentation is an alternative to linear methods such as the DCT. Although offering attractive features: edge preservation and lack of ringing, it can introduce artefacts such as spurious edges in the reconstructed video sequence. In this paper, a smoothing algorithm is described that reduces this problem and yields s...
متن کاملRemoval of blocking and ringing artifacts in transform coded images
Presently Block-based Discrete Cosine Transform (BDCT) image coding techniques are widely used in image and video compression applications such as JPEG and MPEG. At a moderate bit rate, BDCT is usually a quite satisfactory solution to most of practical coding applications. However, for high compression it produces noticeable blocking and ringing artifacts in the decompressed image. In this pape...
متن کاملImage restoration for frame- and object-based video coding using an adaptive constrained least-squares approach
Especially at low bit-rates current DCT-based video coding standards su!er from the disadvantage that coarse quantization and a rigid block structure result in noticeable blocking and ringing noise. In this paper we propose a spatially adaptive method for reduction of these coding artifacts based on the principle of constrained least-squares image restoration. A strictly local "lter is develope...
متن کاملScalable Image Coder Mixing DCT and Triangular Meshes
In this paper a new very low bit rate scalable encoding principle is presented. It is based on hierarchical triangular mesh encoding combined with triangle based DCT coding. Affine or DCT approximation is selected according to best rate distorsion trade-off. In this way our coder demonstrates advantages at very low bit rates avoiding the traditional block or ringing artefacts of current DCT or ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2003