Learn More
A scheme for image compression that takes into account psychovisual features both in the space and frequency domains is proposed. This method involves two steps. First, a wavelet transform used in order to obtain a set of biorthogonal subclasses of images: the original image is decomposed at different scales using a pyramidal algorithm architecture. The(More)
Introduces a new image coding scheme using lattice vector quantization. The proposed method involves two steps: biorthogonal wavelet transform of the image, and lattice vector quantization of wavelet coefficients. In order to obtain a compromise between minimum distortion and bit rate, we must truncate and scale the lattice suitably. To meet this goal, we(More)
We present a simple yet efficient scalable scheme for wavelet-based video coders, able to provide on-demand spatial, temporal, and SNR scalability, and fully compatible with the still-image coding standard JPEG2000. Whereas hybrid video coders must undergo significant changes in order to support scalability, our coder only requires a specific wavelet filter(More)
We present an efficient compression scheme for animated sequences of triangular meshes of the same connectivity. The proposed algorithm exploits the temporal coherence of the geometry component by using a temporal wavelet filtering. The quantization of the resulting wavelet coefficients is then optimized by a bit allocation process. This process dispatches(More)
We propose a new wavelet compression algorithm based on the rate-distortion optimization for densely sampled triangular meshes. This algorithm includes the normal remesher, a wavelet transform, and an original bit allocation optimizing the quanti-zation of the wavelet coefficients. The allocation process minimizes the reconstruction error for a given bit(More)
Presents a new scheme for fractal image compression based on adaptive Delaunay triangulation. Such a partition is computed on an initial set of points obtained with a split and merge algorithm in a grey level dependent way. The triangulation is thus fully flexible and returns a limited number of blocks allowing good compression ratios. Moreover, a second(More)
This paper proposes a new method for the design of lifting filters to compute a multidimensional nonseparable wavelet transform. Our approach is stated in the general case, and is illustrated for the 2-D separable and for the quincunx images. Results are shown for the JPEG2000 database and for satellite images acquired on a quincunx sampling grid. The(More)
The objective of this paper is to propose an efficient model-based bit allocation process optimizing the performances of a wavelet coder for semiregular meshes. More precisely, this process should compute the best quantizers for the wavelet coefficient subbands that minimize the reconstructed mean square error for one specific target bitrate. In order to(More)
Wavelet coding has been shown to be better than DCT coding. This method outperforms DCT JPEG codec and moreover allows scalability. 2D DWT can be easily extended to 3D and thus applied to video coding [1, 2, 3, 4, 5, 6]. However 3D subband coding of video suffers from two drawbacks. The first one is the memory complexity required for coding 3D blocks. The(More)