||An Error Resilience and Concealment Method for Line-based Wavelet Image Compressions
||Ho-Young Kim;Seong-Won Lee
||Line-based wavelet image compression; Error-resilient coding; Error concealment
||Recently, some wavelet-based line compression methods for low-cost high-resolution image transmission have been studied. With these line compression methods, which are a combination of the multilevel discrete wavelet transform, predictive coding, and entropy coding, communications errors on the transmission channel can cause an image quality?degradation phenomenon of various line shapes. In this paper, we analyze image degradation patterns of wavelet-based hybrid line compression techniques caused by communications errors. Then, we propose an image quality?improvement method including a low-cost resynchronization technique by using a periodic reset to prevent the error propagation phenomenon of predictive coding, as well as an error concealment technique that uses only one additional line memory in the variable reference line?based decoder to improve degraded image quality. Experimental results showed that the proposed method achieved better image quality than the conventional techniques at the small expense of compression ratio while satisfying low-cost design conditions pursued by existing line compression systems.