JPEG-compliant image coding with adaptive pre-/post-filtering

In this paper we propose an image coding scheme with adaptive pre-/post-filtering which produces a fully compliant JPEG bitstream. The basic idea is to introduce pre-filtering to improve the coding performance and post-filtering to reduce JPEG blocking artifacts. The adaptivity of the pre-/post-filters is achieved by varying their filter supports based on two criteria: rate-distortion optimization (RD-opt) and over-/under-flow. Experiments show that despite keeping intact JPEG baseline coding, our proposed coding scheme with these two criteria can improve not only the objective quality (0.3-1.5 dB PSNR gain), but also yield superior visual quality by preserving edge details and mitigating blocking artifacts. Our proposed algorithm is competitive with state-of-the-art deblocking algorithms