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This paper presents a compression framework for light-field images. The main idea of our approach is exploiting the similarity across sub-aperture images extracted from light-field data to improve encoding performance. For this purpose we propose a variational optimisation approach to estimate the disparity map from light-field images and then apply it to a motion-compensated wavelet lifting scheme. Making use of JPEG2000 for coding all high-/low-pass sub-band views as well as disparity map, our approach can therefore support both lossless and lossy compression.

This paper addresses the problem of image compression using
sparse representations. We propose a variant of autoencoder
called Stochastic Winner-Take-All Auto-Encoder
(SWTA AE). “Winner-Take-All” means that image patches
compete with one another when computing their sparse representation
and “Stochastic” indicates that a stochastic hyperparameter
rules this competition during training. Unlike
auto-encoders, SWTA AE performs variable rate image compression
for images of any size after a single training, which

Existed inherent sparsity of natural images in some domains helps to reconstruct the signal with a lower number of measurements. To benefit from the sparsity, one should solve the reweighted $\ell_{1}$-norm minimization algorithms. Although, the existed reweighted $\ell_{1}$-norm minimization approaches work well for k-sparse signals, but, the performance of these methods for compressible signals are not competitive with unweighted one.

Recently, multidimensional signal reconstruction using a low number of measurements is of great interest. Therefore, an effective sampling scheme which should acquire the most information of signal using a low number of measurements is required. In this paper, we study a novel cube-based method for sampling and reconstruction of multidimensional signals. First, inspired by the block-based compressive sensing (BCS), we divide a group of pictures (GoP) in a video sequence into cubes. By this way, we can easily store the measurement matrix and also easily can generate the sparsifying basis.

Conventional pixel-domain block matching temporal (inter) prediction is suboptimal, since it ignores the underlying spatial correlation. Hence in our recent research we proposed transform domain temporal prediction (TDTP), wherein spatially de-correlated transform coefficients are individually predicted. Later we proposed extended block TDTP (EB-TDTP), which fully exploits spatial correlation around reference block boundaries. However, the transform domain temporal correlation exploited by (EB-)TDTP interferes with the frequency response of sub-pixel interpolation filters.

Recent MPEG video compression standards are still block-based: blocks of pixels are sequentially coded using spatial or temporal prediction schemes. For each block, a vector of coding parameters has to be selected. In order to limit the complexity of this decision, independence between blocks is assumed, and coding parameters are locally optimized to maximize the coding efficiency. Few studies have investigated the benefits of inter-block dependencies consideration using Joint Rate-Distortion Optimization (JRDO), especially in Intra coding.

With the quad-tree based coding structure and more flexible intra-modes, the coding efficiency provided by intra-technique in inter-frames of HEVC is much higher than the preceding standard H.264/AVC. However, the computing complexity is also significantly increased. Although only a few CUs are encoded as intra-mode in inter-frames finally, almost all CUs need to be checked all the intra-options to obtain the optimal mode, which may be in fact unnecessary.