We propose a discrete cosine transform (DCT) analysis-based adaptive deblocking algorithm to reduce the block discontinuities. First we analyze the properties of the one-dimensional DCT coefficients. Based on this analysis, we utilize two adjacent vectors to classify the vector-containing block boundary into three models. For each model, we apply different filters according to the local properties. Comprehensive experiments indicate that the proposed method outperforms a large number of deblocking methods in the literature in terms of the evaluation of peak signal-to-noise ratio, perceptual quality, and computational complexity. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.OE.51.6.067011]