Fast image restoration for reducing blocking artifacts
Sang K. Lee, Tae Y. Kim, Joonki Paik, Yo‐Sung Ho · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1998
DCT-based coding techniques for image data compression are widely used owing to good performance with moderate hardware complexity. In very low bit rate applications, however, block- based image compression techniques usually exhibit significant quality degradation, which is called as the blocking artifact. In this paper, we propose an adaptive fast image restoration method that is suitable for reducing the blocking artifact. The proposed restoration filter is based on an observation that the quantization operation is a nonlinear and many-to-one mapping operator. We have developed an approximated version of the constrained optimization technique for image restoration by removing the nonlinear and space-varying degradation operator. The proposed method can be used as a post-processor at the decoder of video coding systems for digital TV, video on demand (VOD), or digital versatile disc (DVD) applications.