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A discrete cosine transform (DCT) can be easily implemented in software and hardware for the JPEG and MPEG formats. However, even though some integer DCTs (IntDCTs) for lossless-to-lossy image coding have been proposed, such transform requires redesigned devices. This paper proposes a hardware-friendly IntDCT that can be applied to both lossless and lossy(More)
This paper introduces one of the image transform methods using M-channel paraunitary filterbanks (PUFBs) based on Householder matirx. First, redundant parameters of PUFB are eliminated by using the fact that they can be factorized into Givens rotation matices. Next, we propose an eliminating redundant parameters method based on Householder matrix using(More)
Several lifting-based filter banks (LBFBs) are proposed for lossless-to-lossy image coding. However, the conventional methods can not achieve good coding performance due to many rounding operations, and they may have wide dynamic range of lifting coefficients due to inverse matrix. This paper presents a more practical lifting factorization of M-channel(More)
In this paper, we propose a two dimensional (2D) non-separable adaptive directional lifting (ADL) structure of discrete wavelet transform (DWT) and its image coding application. Conventionally, we have proposed a polyphase representation of a 2D non-separable lifting structure of DWT. We generalize the polyphase representation in this paper and one(More)
Generalized block-lifting factorization of M-channel (M > 2) biorthogonal filter banks (BOFBs) for lossy-to-lossless image coding is presented in this paper. Since the proposed block-lifting structure is more general than the conventional lifting factorizations and does NOT require many restrictions such as paraunitary, number of channels, and(More)
SUMMARY This paper presents an integer discrete cosine transform (IntDCT) with only dyadic values such as k/2 n (k, n ∈ N). Although some conventional IntDCTs have been proposed, they are not suitable for lossless-to-lossy image coding in low-bit-word-length (coefficients) due to the degradation of the frequency decomposition performance in the system.(More)
This paper presents a novel lifting factorization of discrete cosine transform type-II and IV (DCT-II and IV). Although some conventional integer DCT-IIs (IntDCT-IIs) with block size 8 have been proposed, they are not generalized as arbitrary block size M. Using block lifting factorization which has an efficient structure for lossless-to-lossy image coding,(More)
The multiplierless fast Fourier transform (FFT) with dyadic-valued (rational) coefficients is important for many signal processing tools. The proposed lifting based FFT (L-FFT) based on fast Hartley transform (FHT) has a simpler structure than existing ones because fewer lifting steps need to be approximated. In addition, it has a structure of real-valued(More)
Some adaptive image interpolation methods have been proposed to create higher visual quality images than traditional interpolation methods such as bicubic interpolation. These methods, however, often suffer from high computational costs and unnatural texture interpolation. This paper proposes a novel edge-adaptive image interpolation method using an(More)