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A depth map represents three-dimensional (3D) data and is used for depth image-based rendering (DIBR) to synthesize virtual views. Since quality of the rendering view depends on that of the depth map, we should encode the depth map by maintaining the original quality. However, lossless depth coding requires a large amount of bits to carry the encoded depth map over the network. Thus, in this paper,...
This paper considers a multicast scenario and compares the average reception quality obtained when combining multiple description coding (MDC) and network coding (NC). Plain (single description) network coding (NC-SDC) serves as reference. In the considered scenario, a single source is multicast to several receivers with various channel conditions. Contrary to a NC-SDC scheme, unable to recover the...
This paper is concerned with transform coding of correlated sources in conjunction with variable rate quantization at high resolution. The approach builds on our prior work on optimality conditions for transform coding in the point-to-point setting. The first contribution involves transform coding with decoder side information. In this setting, side information is only available to the decoder, whereas...
Enormous amounts of GPS trajectories, which record users' spatial and temporal information, are collected by geo-positioning mobile phones in recent years. The massive volumes of trajectory data bring about heavy burdens for both network transmission and data storage. To overcome these difficulties, a number of compression algorithms have been proposed by reducing the number of points in the trajectory...
Embedded quantization is a mechanism employed by lossy image coding systems to successively refine the distortion of an image. Commonly, it is conducted through a uniform scalar dead zone quantizer (USDQ) together with a bitplane coding strategy (BPC). Although this scheme is convenient for current hardware architectures and achieves competitive coding performance, it establishes the embedded quantizer...
Stereo interleaving video coding receives considerable attention due to its desirable property of being compatible with 2D video coding standards. The errors caused by sub sampling (causing distortion between subsamplinginterpolated image and the original full resolution one) and by quantization during compression lead to the final distortion in stereo interleaving video coding. In this paper, the...
High data rates and multiple channel profiles of a MIMO system are naturally well-suited to carry video content. However, a video communication scheme to exploit these desirable properties of MIMO systems is widely unexplored. Even the most sophisticated MIMO rate adaptation methods rely on channel BER which shows a monotonic decrease as the channel quality improves. However, video quality, for which...
In this paper, a lossy data compression for a sparse histogram image signal is proposed. It is extended from an existing lossless coding which is based on a lossless histogram packing and a lossless coding. We introduce a lossy mapping, which has less computational load than the rate-distortion optimized Lloyd-Max quantization, and combine it with a lossless coding. It was confirmed that the proposed...
A practical approach to designing distributed transform codes for high-dimensional correlated Gaussian vectors is presented. In this approach, source-splitting based on linear approximations is used to achieve arbitrary rate-pairs, by using only Wyner-Ziv (WZ) quantizers. The optimal bit-allocation among a dependent set of WZ quantizers is found by using a tree-search algorithm. Experimental results...
Vision field describes the real world visual information by summarizing the seven-dimensional plenoptic function into three domains: view, light, time, from which a better understanding of previous 3D capture and reconstruction systems can be provided. In this paper, we first show how to reconstruct 3D spatial information from all the three attributes of the vision field, namely full-space vision...
Video content is routinely acquired and distributed in digital format. Therefore, it is customary to have the content encoded multiple times. In this paper we consider a processing chain of two coding steps and we propose a method that aims at identifying the type of codec used in the first step, by analyzing its coding-based footprints. The method relies on the fact that lossy coding is an almost...
Compressing a query image's signature via vocabulary coding is an effective approach to low bit rate mobile visual search. State-of-the-art methods concentrate on offline learning a codebook from an initial large vocabulary. Over a large heterogeneous reference database, learning a single codebook may not suffice for maximally removing redundant codewords for vocabulary based compact descriptor. In...
Distributed Video Coding (DVC) in transform domains could yield significant coding gains over the pixel domain. While employing different coding modes in DVC, it is still difficult to fully compress the source data without increasing the complexity at the encoder side. In this paper, we first propose a particular Run-Length-Coding (RLC) coding mode to efficiently compress the continuous zero symbols...
Rate distortion optimization (RDO) algorithm plays the vital role in the up to date hybrid video codec H.264/AVC. The RDO algorithm of H.264/AVC reference software is built up by assuming that the transformed residues are memoryless variables. However, our experiments reveal that, for some sequences, the strong temporal correlations exist in the prediction residues. This paper extends the Lagrangian...
A hash based identification method of JPEG 2000 images with different coding parameters is presented. The method correctly identifies the compressed JPEG 2000 images encoded even if there are difference in the coding parameters, such as coding-rate and quantization step sizes. A new algorithm is introduced to calculate hash values from the number of zero-bit-planes that can be extracted from the JPEG...
In this paper, we study the achievable rate region of two-user Gaussian broadcast channel (GBC) when the messages to be transmitted to both the users take values from finite signal sets and the received signal is quantized at both the users. We refer to this channel as quantized broadcast channel (QBC). We first observe that the capacity region defined for a GBC does not carry over as such to QBC...
This paper proposes a new coding scheme which jointly applies perceptual quality metrics to prediction, quantization and rate-distortion optimization (RDO) within the High Efficiency Video Coding (HEVC) framework. A new prediction approach which uses template matching is introduced. The template matching uses a structural similarity metric (SSIM) and a Just-Noticeable Distortion (JND) model. The matched...
An efficient and accurate R-Q model is greatly important for intra-frame rate control of the latest High Efficiency Video Coding (HEVC) standard. However, previous methods pay more attention to the gradient based rate quantization (R-Q) model for the intra-frame rate control. In this paper, we analyze the drawbacks of the gradient based frame complexity measure when applied different Quantization...
As the High dynamic range (HDR) images generally have more than 10 bit/1024 colors per channel, its enormous data size often needs to be reduced when transmitting or storing the images. Thus development for functional compression is one of important research topics. Recently a lot of techniques for the HDR image compression are being suggested, and several two-layer coding algorithms which separately...
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