Abstract: JPEG-LS standard performs lossless and near-lossless high quality compression for still images.Its predictive coding is based on simple median edge detection scheme，but the redundancy is not well reduced.This paper explores the continuity property and the relativity of local pixel texture.It studies the selection of reference pixels，construction of texture-based nonlinear classification predictor，and design of prediction parameters.The gradient detection capability is enhanced，and a new four-order classification predictor is proposed.It is confirmed that the prediction performance is effectively promoted with low operation complexity.