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Chih-peng Fan - One of the best experts on this subject based on the ideXlab platform.
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efficient fast 1 d 8 times 8 inverse Integer Transform for vc 1 application
IEEE Transactions on Circuits and Systems for Video Technology, 2009Co-Authors: Chih-peng FanAbstract:In this paper, the one-dimensional (1-D) fast 8times8 inverse Integer Transform algorithm for Windows Media Video 9 (WMV-9/VC-1) is proposed. Based on the symmetric property of the Integer Transform matrix and the matrix operations, which denote the row/column permutations and the matrix decompositions, the efficient fast 1-D 8times8 inverse Integer Transform is developed. Therefore, the computational complexities of the proposed fast inverse Transform are smaller than those of the direct method and the previous fast method. With low complexity, the proposed fast algorithm is suitable to accelerate the video coding computations.
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Efficient Fast 1-D 8 $\,\times\,$ 8 Inverse Integer Transform for VC-1 Application
IEEE Transactions on Circuits and Systems for Video Technology, 2009Co-Authors: Chih-peng FanAbstract:In this paper, the one-dimensional (1-D) fast 8times8 inverse Integer Transform algorithm for Windows Media Video 9 (WMV-9/VC-1) is proposed. Based on the symmetric property of the Integer Transform matrix and the matrix operations, which denote the row/column permutations and the matrix decompositions, the efficient fast 1-D 8times8 inverse Integer Transform is developed. Therefore, the computational complexities of the proposed fast inverse Transform are smaller than those of the direct method and the previous fast method. With low complexity, the proposed fast algorithm is suitable to accelerate the video coding computations.
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efficient low cost sharing design of fast 1 d inverse Integer Transform algorithms for h 264 avc and vc 1
IEEE Signal Processing Letters, 2008Co-Authors: Chih-peng FanAbstract:In this letter, the fast one-dimensional (1-D) algorithms and their sharing design for 1-D inverse Integer Transforms of H.264/AVC and VC-1 are proposed by using the matrix decompositions with the sparse matrices and the matrix offset computations. The computational complexities of the proposed fast 1-D 4 times 4 and 8 times 8 inverse Integer Transforms for H.264/AVC are the same as those of the previous fast methods. Then the shift operations of the proposed fast 1-D inverse Integer Transform for VC-1 are equivalent to those of the previous fast method. For playback environments, the video decoder can support the multiple modes, which include H.264/AVC and VC-1 video standards. The proposed hardware sharing architecture requires lower hardware cost than the individual and separate design for the VLSI realization.
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Efficient Low-Cost Sharing Design of Fast 1-D Inverse Integer Transform Algorithms for H.264/AVC and VC-1
IEEE Signal Processing Letters, 2008Co-Authors: Chih-peng FanAbstract:In this letter, the fast one-dimensional (1-D) algorithms and their sharing design for 1-D inverse Integer Transforms of H.264/AVC and VC-1 are proposed by using the matrix decompositions with the sparse matrices and the matrix offset computations. The computational complexities of the proposed fast 1-D 4 times 4 and 8 times 8 inverse Integer Transforms for H.264/AVC are the same as those of the previous fast methods. Then the shift operations of the proposed fast 1-D inverse Integer Transform for VC-1 are equivalent to those of the previous fast method. For playback environments, the video decoder can support the multiple modes, which include H.264/AVC and VC-1 video standards. The proposed hardware sharing architecture requires lower hardware cost than the individual and separate design for the VLSI realization.
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Fast 2-Dimensional 8 × 8 Integer Transform Algorithm Design for H.264/AVC Fidelity Range Extensions*This work was supported by the National Science Council, Taiwan, R.O.C., under Grant NSC95-2220-E-005-006.
IEICE Transactions on Information and Systems, 2006Co-Authors: Chih-peng FanAbstract:In this letter, efficient two-dimensional (2-D) fast algorithms for realizations of 8 × 8 forward and inverse Integer Transforms in H.264/AVC fidelity range extensions (FRExt) are proposed. Based on matrix factorizations with Kronecker product and direct sum operations, efficient fast 2-D 8 × 8 forward and inverse Integer Transforms can be derived from the one-dimensional (1-D) fast 8 × 8 forward and inverse Integer Transforms through matrix operations. The proposed fast 2-D 8 × 8 forward and inverse Integer Transform designs don't require transpose memory in hardware realizations. The fast 2-D 8 × 8 Integer Transforms require fewer latency delays and provide a larger throughput rate than the row-column based method. With regular modularity, the proposed fast algorithms are suitable for VLSI implementations to achieve H.264/AVC FRExt high-profile signal processing.
Waikuen Cham - One of the best experts on this subject based on the ideXlab platform.
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simple order 16 Integer Transform for video coding
International Conference on Image Processing, 2010Co-Authors: Chikeung Fong, Waikuen ChamAbstract:Transform is a very important coding tool in video coding. Simple order-16 Integer Transform, proposed in this paper, is a simple, low computational complexity Transform but has high coding efficiency. It is simpler than other order-16 Transforms previously proposed but it can achieve similar coding performance. It is shown that it significantly reduces the bit rate up to 18.49%. On average, it reduces the bit rate by 8.71%. It is comparable with other proposed Transforms but significantly simpler.
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ICIP - Simple order-16 Integer Transform for video coding
2010 IEEE International Conference on Image Processing, 2010Co-Authors: Chikeung Fong, Waikuen ChamAbstract:Transform is a very important coding tool in video coding. Simple order-16 Integer Transform, proposed in this paper, is a simple, low computational complexity Transform but has high coding efficiency. It is simpler than other order-16 Transforms previously proposed but it can achieve similar coding performance. It is shown that it significantly reduces the bit rate up to 18.49%. On average, it reduces the bit rate by 8.71%. It is comparable with other proposed Transforms but significantly simpler.
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The Technique of Prescaled Integer Transform: Concept, Design and Applications
IEEE Transactions on Circuits and Systems for Video Technology, 2008Co-Authors: Cixun Zhang, Jian Lou, Waikuen Cham, Jie DongAbstract:Integer cosine Transform (ICT) is adopted by H.264/AVC for its bit-exact implementation and significant complexity reduction compared to the discrete cosine Transform (DCT) with an impact in peak signal-to-noise ratio (PSNR) of less than 0.02 dB. In this paper, a new technique, named prescaled Integer Transform (PIT), is proposed. With PIT, while all the merits of ICT are kept, the implementation complexity of decoder is further reduced compared to corresponding conventional ICT, which is especially important and beneficial for implementation on low-end processors. Since not all PIT kernels are good in respect of coding efficiency, design rules that lead to good PIT kernels are considered in this paper. Different types of PIT and their target applications are examined. Both fixed block-size Transform and adaptive block-size Transform (ABT) schemes of PIT are also studied. Experimental results show that no penalty in performance is observed with PIT when the PIT kernels employed are derived from the design rules. Up to 0.2 dB of improvement in PSNR for all intra frame coding compared to H.264/AVC can be achieved and the subjective quality is also slightly improved when PIT scheme is carefully designed. Using the same concept, a variation of PIT, post-scaled Integer Transform, can also be potentially designed to simplify the encoder in some special applications. PIT has been adopted in audio video coding standard (AVS), Chinese National Coding standard.
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the technique of pre scaled Integer Transform
International Symposium on Circuits and Systems, 2005Co-Authors: Cixun Zhang, Jian Lou, Jie Dong, Waikuen ChamAbstract:The Integer cosine Transform (ICT) is adopted by H.264/AVC for its bit-exact implementation and significant complexity reduction compared to the discrete cosine Transform (DCT) with an impact in peak signal-to-noise ratio (PSNR) of less than 0.02dB. In this paper, a new technique, named pre-scaled Integer Transform (PIT), is proposed. With PIT, the implementation complexity is further reduced compared to conventional ICT, especially for low-end processors while all the merits of ICT are kept. Extensive experiments show that no obvious penalty in performance is observed but rather a slight gain in PSNR is obtained by using PIT when the Integer Transform matrix used meets certain requirements.
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ISCAS (1) - The technique of pre-scaled Integer Transform
2005 IEEE International Symposium on Circuits and Systems, 1Co-Authors: Cixun Zhang, Jian Lou, Jie Dong, Waikuen ChamAbstract:The Integer cosine Transform (ICT) is adopted by H.264/AVC for its bit-exact implementation and significant complexity reduction compared to the discrete cosine Transform (DCT) with an impact in peak signal-to-noise ratio (PSNR) of less than 0.02dB. In this paper, a new technique, named pre-scaled Integer Transform (PIT), is proposed. With PIT, the implementation complexity is further reduced compared to conventional ICT, especially for low-end processors while all the merits of ICT are kept. Extensive experiments show that no obvious penalty in performance is observed but rather a slight gain in PSNR is obtained by using PIT when the Integer Transform matrix used meets certain requirements.
Bin Yang - One of the best experts on this subject based on the ideXlab platform.
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a novel Integer Transform for efficient reversible watermarking
International Conference on Pattern Recognition, 2012Co-Authors: Xinlu Gui, Bin YangAbstract:In this paper, based on a novel Integer Transform, an efficient reversible image watermarking method is proposed. The Integer Transform is a generalization of some previous works. It can be applied to a pixel block of arbitrary size with adjustable capacities. Moreover, this Transform is conducted by conditionally embedding data only when the estimated distortion is acceptable. By this approach, our method can effectively reduce the embedding distortion while providing a high capacity. The experimental results show that the proposed method outperforms some state-of-the-art works.
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Adaptive reversible data hiding scheme based on Integer Transform
Signal Processing, 2012Co-Authors: Fei Peng, Bin YangAbstract:In this paper, we present a new reversible data hiding algorithm based on Integer Transform and adaptive embedding. According to the image block type determined by the pre-estimated distortion, the parameter in Integer Transform is adaptively selected in different blocks. This allows embedding more data bits into smooth blocks while avoiding large distortion generated by noisy ones, and thus enables very high capacity with good image quality. For instance, by the proposed method, we can embed as high as 2.17bits per pixel into Lena image with a reasonable PSNR of 20.71dB. Experimental results demonstrate that the proposed method outperforms some state-of-the-art algorithms, especially for high capacity case.
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high capacity reversible image watermarking based on Integer Transform
International Conference on Image Processing, 2010Co-Authors: Chao Wang, Bin YangAbstract:Many reversible watermarking algorithms have been proposed in the literature, and all of these solutions put emphasis on high embedding capacity with low distortion. In this paper, a novel reversible image watermarking method based on Integer Transform is presented. Through taking pixel block of arbitrary size as embedding unit, the method can provide a very high embedding capacity. For instance, it can embed as large as 1.85 bits per pixel in “Lena”. Besides, by pre-estimating the embedding distortion, one can suitably select embeddable blocks so that the visual quality of the watermarked image is well guaranteed. Furthermore, extensive experiments show that the novel method performs better than some state-of-the-art algorithms.
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efficient generalized Integer Transform for reversible watermarking
IEEE Signal Processing Letters, 2010Co-Authors: Xiang Wang, Xiaolong Li, Bin YangAbstract:In this letter, an efficient Integer Transform based reversible watermarking is proposed. We first show that Tian's difference expansion (DE) technique can be reformulated as an Integer Transform. Then, a generalized Integer Transform and a payload-dependent location map are constructed to extend the DE technique to the pixel blocks of arbitrary length. Meanwhile, the distortion can be controlled by preferentially selecting embeddable blocks that introduce less distortion. Finally, the superiority of the proposed method is experimental verified by comparing with other existing schemes.
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reversible image watermarking based on a generalized Integer Transform
International Conference on Acoustics Speech and Signal Processing, 2010Co-Authors: Xudong Chen, Bin Yang, Yingmin TangAbstract:In this paper, a recently proposed reversible image watermarking algorithm based on reversible contrast mapping (RCM) is further developed. The Integer Transform, RCM, which is originally defined on a pair of Integers, is extended to Integer array of arbitrary length. Based on this generalization, the embedding capacity can be significantly increased. Meanwhile, the embedding distortion is well controlled by a suitable selection of embeddable pixel blocks. In fact, the hidden data is priorly embedded into the blocks that introduce less distortion. Furthermore, the proposed scheme does not need additional data compression, and it has low computational complexity. The experiments verify that the novel scheme outperforms the original RCM-based method and some state-of-the-art reversible watermarking algorithms, especially the ones based on Integer Transform.
Yongdong Zhang - One of the best experts on this subject based on the ideXlab platform.
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A Fast Scheme for Converting DCT Coefficients to H.264/AVC Integer Transform Coefficients
Lecture Notes in Computer Science, 2006Co-Authors: Gao Chen, Shouxun Lin, Yongdong ZhangAbstract:Converting MPEG-2 8-tap discrete cosine Transform (DCT) coefficients to H.264/AVC 4-tap Integer Transform (IT) coefficients is one of the indispensable operations for MPEG-2 to H.264 Transform domain transcoding. In this paper, we propose a novel Transform kernel matrix based on the factorization of DCT to perform this operation directly in Transform domain. Furthermore, additional reduction in computation can be obtained by taking advantage of the fact that most of the 8x8 DCT blocks in real video sequences only have nonzero coefficients in the upper left 4x4 quadrant. Relative to Jun Xin's method, the proposed method saves 16 operations in the worst case and 440 operations in the best case for each 8x8 DCT block. Experimental results also show that the proposed method efficiently reduces the computational cost up to 42.9% with negligible degradation in video quality. Hence, the proposed method can be efficiently used in the real-time and high capacity MPEG-2 to H.264 Transform domain transcoding.
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a fast scheme for converting dct coefficients to h 264 avc Integer Transform coefficients
Lecture Notes in Computer Science, 2006Co-Authors: Gao Chen, Shouxun Lin, Yongdong ZhangAbstract:Converting MPEG-2 8-tap discrete cosine Transform (DCT) coefficients to H.264/AVC 4-tap Integer Transform (IT) coefficients is one of the indispensable operations for MPEG-2 to H.264 Transform domain transcoding. In this paper, we propose a novel Transform kernel matrix based on the factorization of DCT to perform this operation directly in Transform domain. Furthermore, additional reduction in computation can be obtained by taking advantage of the fact that most of the 8x8 DCT blocks in real video sequences only have nonzero coefficients in the upper left 4x4 quadrant. Relative to Jun Xin's method, the proposed method saves 16 operations in the worst case and 440 operations in the best case for each 8x8 DCT block. Experimental results also show that the proposed method efficiently reduces the computational cost up to 42.9% with negligible degradation in video quality. Hence, the proposed method can be efficiently used in the real-time and high capacity MPEG-2 to H.264 Transform domain transcoding.
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ICIAR (1) - A fast scheme for converting DCT coefficients to H.264/AVC Integer Transform coefficients
Lecture Notes in Computer Science, 2006Co-Authors: Gao Chen, Shouxun Lin, Yongdong ZhangAbstract:Converting MPEG-2 8-tap discrete cosine Transform (DCT) coefficients to H.264/AVC 4-tap Integer Transform (IT) coefficients is one of the indispensable operations for MPEG-2 to H.264 Transform domain transcoding. In this paper, we propose a novel Transform kernel matrix based on the factorization of DCT to perform this operation directly in Transform domain. Furthermore, additional reduction in computation can be obtained by taking advantage of the fact that most of the 8×8 DCT blocks in real video sequences only have nonzero coefficients in the upper left 4×4 quadrant. Relative to Jun Xin’s method, the proposed method saves 16 operations in the worst case and 440 operations in the best case for each 8×8 DCT block. Experimental results also show that the proposed method efficiently reduces the computational cost up to 42.9% with negligible degradation in video quality. Hence, the proposed method can be efficiently used in the real-time and high capacity MPEG-2 to H.264 Transform domain transcoding.
Gao Chen - One of the best experts on this subject based on the ideXlab platform.
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A Fast Scheme for Converting DCT Coefficients to H.264/AVC Integer Transform Coefficients
Lecture Notes in Computer Science, 2006Co-Authors: Gao Chen, Shouxun Lin, Yongdong ZhangAbstract:Converting MPEG-2 8-tap discrete cosine Transform (DCT) coefficients to H.264/AVC 4-tap Integer Transform (IT) coefficients is one of the indispensable operations for MPEG-2 to H.264 Transform domain transcoding. In this paper, we propose a novel Transform kernel matrix based on the factorization of DCT to perform this operation directly in Transform domain. Furthermore, additional reduction in computation can be obtained by taking advantage of the fact that most of the 8x8 DCT blocks in real video sequences only have nonzero coefficients in the upper left 4x4 quadrant. Relative to Jun Xin's method, the proposed method saves 16 operations in the worst case and 440 operations in the best case for each 8x8 DCT block. Experimental results also show that the proposed method efficiently reduces the computational cost up to 42.9% with negligible degradation in video quality. Hence, the proposed method can be efficiently used in the real-time and high capacity MPEG-2 to H.264 Transform domain transcoding.
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a fast scheme for converting dct coefficients to h 264 avc Integer Transform coefficients
Lecture Notes in Computer Science, 2006Co-Authors: Gao Chen, Shouxun Lin, Yongdong ZhangAbstract:Converting MPEG-2 8-tap discrete cosine Transform (DCT) coefficients to H.264/AVC 4-tap Integer Transform (IT) coefficients is one of the indispensable operations for MPEG-2 to H.264 Transform domain transcoding. In this paper, we propose a novel Transform kernel matrix based on the factorization of DCT to perform this operation directly in Transform domain. Furthermore, additional reduction in computation can be obtained by taking advantage of the fact that most of the 8x8 DCT blocks in real video sequences only have nonzero coefficients in the upper left 4x4 quadrant. Relative to Jun Xin's method, the proposed method saves 16 operations in the worst case and 440 operations in the best case for each 8x8 DCT block. Experimental results also show that the proposed method efficiently reduces the computational cost up to 42.9% with negligible degradation in video quality. Hence, the proposed method can be efficiently used in the real-time and high capacity MPEG-2 to H.264 Transform domain transcoding.
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ICIAR (1) - A fast scheme for converting DCT coefficients to H.264/AVC Integer Transform coefficients
Lecture Notes in Computer Science, 2006Co-Authors: Gao Chen, Shouxun Lin, Yongdong ZhangAbstract:Converting MPEG-2 8-tap discrete cosine Transform (DCT) coefficients to H.264/AVC 4-tap Integer Transform (IT) coefficients is one of the indispensable operations for MPEG-2 to H.264 Transform domain transcoding. In this paper, we propose a novel Transform kernel matrix based on the factorization of DCT to perform this operation directly in Transform domain. Furthermore, additional reduction in computation can be obtained by taking advantage of the fact that most of the 8×8 DCT blocks in real video sequences only have nonzero coefficients in the upper left 4×4 quadrant. Relative to Jun Xin’s method, the proposed method saves 16 operations in the worst case and 440 operations in the best case for each 8×8 DCT block. Experimental results also show that the proposed method efficiently reduces the computational cost up to 42.9% with negligible degradation in video quality. Hence, the proposed method can be efficiently used in the real-time and high capacity MPEG-2 to H.264 Transform domain transcoding.