EFFICIENT PARALLEL FRAMEWORK FOR H.264 AVC DEBLOCKING FILTER ON MANY-CORE PLATFORM Yongdong Zhang, Member, IEEE, Chenggang Yan, Feng Dai, and Yike Ma

Outline  Introduction  Method  A. Boundary Strength Computation (BSC)  B. Edge Discrimination and Filtering (EDF)  Experimental Results  Q & A

Introduction #1  Deblocking Filter  boundary strength computation (BSC) imbalance  edge discrimination and filtering (EDF) data dependency

Introduction #2  Imbalance stall core1 core2 core3 core4

Introduction #3  Data dependency frame1

Method #1  For every edge, because of complex “if” instructions, they split the deblocking filter into three parts: BSC, ED, and filtering. [39] GSAIM, Chung-Ang University, Seoul, “Variable block-based deblocking filter for H.264/AVC on low-end and low-bit rates terminals,” Signal Process.: Image ommun., vol. 25, no. 4, pp. 255–267, 2010.

Method #2  BSC is determined according to the coding information, such as coding mode and coded residues, which is not influenced by the output of other parts.  The BS value determines the strength of filtering.

Method #3  They find that most of the deblocking computation resources are spent on BSC, which is independent from the EDF.  parallelize BSC first and apply 2D-wavefront method to the EDF.

Method #4  Two problems  BSC Imbalance  EDF Dependency

Method.A  boundary strength computation (BSC)

Method.A #1  They find that the BSC has biased statistical distribution in the temporal domain, which can be modeled as a Markov chain. And they characterize the Markov chain as an empirical transition probability matrix (ETPM).  Huffman tree

Method.A #2  The current edge BS value has something to do with the corresponding edge BS value in a prior same- type frame.

Method.A #3

Method.A #4

Method.A #5

Method.B  edge discrimination and filtering (EDF)

Method.B #1  Luma Component

Method.B #2

Method.B #3  Strong Vertical Boundary(SVB) and Strong Horizontal Boundary(SHB)

Method.B #4

Method.B #5  Several PSAs make up one independent pixel connected area (IPCA).

Method.B #6  Chrome Component [46]

Method.B #7

Method

Experimental Results #1

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Q & A