Block Adaptive Interpolation Filter Using Trained Dictionary for Sub-Pixel Motion Compensation

• Published in: IEEE transactions on circuits and systems for video technology Vol. 22; no. 2; pp. 241 - 248
• Main Authors: CHO, Jaehyun, JEONG, Shin-Cheol, LEE, Dong-Bok, BYUNG CHEOL SONG
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.02.2012; Institute of Electrical and Electronics Engineers
• Subjects: Adaptive interpolation filter; Applied sciences; Circuit properties; Detection, estimation, filtering, equalization, prediction; Dictionaries; Electric, optical and optoelectronic circuits; Electronic circuits; Electronics; Encoding; Exact sciences and technology; Frequency filters; Image processing; Information, signal and communications theory; Interpolation; Motion compensation; Pixel; Signal and communications theory; Signal convertors; Signal processing; Signal, noise; sub-pel motion compensation; super-resolution; Telecommunications and information theory; Training; Wiener filter; Performance evaluation; Dictionaries; Filtering; Superresolution; super-resolution; Switched filters; Updating; Adaptive filter; Algorithm; sub-pel motion compensation; Optimization; Learning; Interpolation; Codec; Accuracy; Simulation; Coding; Linear phase filters; Adaptive interpolation filter; Signal processing; Motion compensation; Low pass filter
• ISSN: 1051-8215; 1558-2205
• DOI: 10.1109/TCSVT.2011.2160601

Adaptive interpolation filtering for sub-pel motion compensation is one of key techniques of ITU-T key technology area (KTA) codec. However, the adaptive interpolation filtering has a limitation in coding efficiency because of its frame-based update strategy of filter coefficients. Although switched interpolation filter with offset is presented as a sort of block-adaptive filtering for KTA codec, its coding efficiency is generally lower than that of the best adaptive interpolation filter. In order to overcome such a problem, this paper presents an advanced block-adaptive interpolation filtering using well-trained dictionaries which store optimized filter coefficients. We derive those filter coefficients by using learning-based super-resolution. The proposed block-adaptive interpolation filtering for quarter-pel motion compensation consists of two steps: up-scaling of half-pel accuracy and subsequent up-scaling of quarter-pel accuracy. The dictionary optimized for each step is employed to produce the precise up-scaled pixels. Simulation results show that the proposed algorithm improves higher coding efficiency than the previous adaptive interpolation filters for KTA.