The JPEG still picture compression standard
Communications of the ACM - Special issue on digital multimedia systems
Techniques and standards for image, video, and audio coding
Techniques and standards for image, video, and audio coding
Digital Signal Processing with Examples in MATLAB
Digital Signal Processing with Examples in MATLAB
An Introduction to Numerical Analysis for Electrical and Computer Engineers
An Introduction to Numerical Analysis for Electrical and Computer Engineers
A new adaptive quantization method to reduce blocking effect
IEEE Transactions on Consumer Electronics
IEEE Transactions on Consumer Electronics
A new adaptive separable median filter for removing blocking effects
IEEE Transactions on Consumer Electronics
Post filtering methods for reducing blocking effects from coded images
IEEE Transactions on Consumer Electronics
Removal of compression artifacts using projections onto convex sets and line process modeling
IEEE Transactions on Image Processing
A deblocking technique for block-transform compressed image using wavelet transform modulus maxima
IEEE Transactions on Image Processing
Theory of projection onto the narrow quantization constraint set and its application
IEEE Transactions on Image Processing
Projection-based spatially adaptive reconstruction of block-transform compressed images
IEEE Transactions on Image Processing
A deblocking algorithm for JPEG compressed images using overcomplete wavelet representations
IEEE Transactions on Circuits and Systems for Video Technology
Reduction of blocking artifact in block-coded images using wavelet transform
IEEE Transactions on Circuits and Systems for Video Technology
IEEE Transactions on Circuits and Systems for Video Technology
A deblocking filter with two separate modes in block-based video coding
IEEE Transactions on Circuits and Systems for Video Technology
A postprocessing method for reducing quantization effects in low bit-rate moving picture coding
IEEE Transactions on Circuits and Systems for Video Technology
Blocking-artifact reduction in block-coded images using wavelet-based subband decomposition
IEEE Transactions on Circuits and Systems for Video Technology
IEEE Transactions on Circuits and Systems for Video Technology
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In this paper, the one-dimensional gray polynomial interpolation (1-D GPI) developed for image enlargement in Hsieh et al. (2007) [27] is applied to reduce the block effect in the block discrete cosine transform (BDCT) image/video coders. Note that the block effect in the BDCT coders results from insufficient bits for transform coefficients. An interpolation approach is proposed to relieve the block effect problem. The proposed approach consists of three stages. First, the input image/frame is down sampled by the direct down sampling (DDS) scheme to reduce the amount of data. Second, the down sampled image/frame is put into a BDCT coder, such as the JPEG and the MPEG-2. Finally, the 1-D GPI is applied to enlarge the decoded image. When the JPEG and the MPEG-2 are used as BDCT coders, the coding systems are called the JPEG-GPI and the MPEG-GPI, respectively. The proposed JPEG-GPI and MPEG-GPI are verified through examples. Simulation results indicate that both the JPEG-GPI and the MPEG-GPI are able to effectively reduce the block effect significantly and therefore the subjective visual quality improved in the given examples. Note that (i) the down sampling scheme in the first stage can be any down sampling scheme other than the DDS, and (ii) the interpolation approach in the third stage may be different from the 1-D GPI. Thus, various down sampling schemes, the nearest neighbor down sampling (NNDS), the bilinear down sampling (BLDS), and the bicubic down sampling (BCDS) schemes are under consideration. These down sampling schemes are used to replace the DDS in the JPEG-GPI and the MPEG-GPI to investigate the effect on the coding performance. The simulation results show that the DDS always gives the highest PSNR for all cases under same condition. Moreover, the 1-GPI is substituted by popular 2-D interpolation approaches, the nearest neighbor interpolation (NNI), the bilinear interpolation (BLI), and the bicubic interpolation (BCI). With the DDS scheme, the simulation results indicate that the JPEG-BLI has a little bit better PSNR than the JPEG-GPI for all cases while similar visual quality of reconstructed image is found. When compared with the MPEG-GPI, the MPEG-BCI has higher PSNR when the DDS is employed. And the reconstructed frames from the MPEG-GPI and the MPEG-BCI have similar visual quality. In summary, by the simulation results the proposed coding system, as expected, is able to significantly reduce the block effect happened in the cases of the low bit rate coding or high compression ratio.