Liang Wei, Fangdong Chen, L. xilinx Wang, Xiaoyang Wu, Shiliang Pu
{"title":"Pixel-Wise Quantization for Image Compression","authors":"Liang Wei, Fangdong Chen, L. xilinx Wang, Xiaoyang Wu, Shiliang Pu","doi":"10.1109/DCC55655.2023.00058","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00058","url":null,"abstract":"This paper proposes a pixel-wise quantization (PWQ) method, which allows to reduce the quantization parameters (QPs) of simple pixels adaptively for the purpose of enhancing the subjective quality, since the distortions on simple pixels are more noticeable than those on complex pixels. For the pixel-wise prediction in Fig. 1, the pixel-wise reconstruction is implemented and the transformation is disabled, where the symbol “=” (or $^{prime prime}vee^{prime prime}/^{prime prime}gt^{prime prime}$) means the current prediction is the average value of the left and right reconstructions (or the upper/left reconstruction). And the PWQ method is applied in the same prediction direction and reconstruction order, with adjusting the current pixel QP $(Q_{pixel})$ adaptively by (1), where Qcb denotes the current block $mathrm{Q}mathrm{P}, T_{pred}$ denotes the predicted texture complexity based on the neighboring reconstruction pixels, and parameters $delta, Q_{jnd}, Q_{thres}$ and Tthres are preseted on the encoder and decoder side. So no additional syntax need to be transmitted in the bitstream. Moreover, for the transformation-off non-pixel-wise prediction, the straightforward extension of the PWQ method is designed to divide the coding block into simple and complex areas based on the above reference pixels, and reduce the pixel QP in simple areas. Qualitative results in Fig. 1 show that, the PWQ method can significantly improve the subjective quality by reducing the distortions on simple pixels, especially in the flat areas near the object edge and between the words on the screen content, and realizes more fine-grained pixel-level quantization compared with the traditional block-level quantization.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126040771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Learning-based Point Cloud Geometry Coding Rate Control","authors":"Manuela Ruivo, André F. R. Guarda, F. Pereira","doi":"10.1109/DCC55655.2023.00079","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00079","url":null,"abstract":"Multimedia applications have been evolving towards providing users with more immersive and realistic experiences. A common way to model the light available for the users’ eyes is the so-called plenoptic function – a powerful 7D representation of light. There are three main types of 3D representation models for the plenoptic function, capable of expressing the light information needed to offer 6-Degrees of Freedom (DoF) experiences, namely light fields, meshes, and Point Clouds (PCs). This paper focuses on PCs since they allow representing and processing objects directly in the 3D space, facilitating user interaction and navigation in a multitude of application domains. Since the illusion of real surfaces is provided by high-density point sets, a good quality of experience requires a rather large set of points to represent a single PC, thus originating huge amounts of data to be stored and/or transmitted. Consequently, PC Coding (PCC) with significant compression levels is a must to reduce the PC data to more manageable sizes and bring PC-based applications to practical deployment. The promising results for image coding led the Joint Photographic Experts Group (JPEG) to launch a standardization project especially targeting Deep Learning (DL)-based PCC, with a final Call for Proposals in January 2022. The best performing response to this call [1] became the JPEG Pleno Learning-based PCC Verification Model (VM), which is the seed codec for the final standard. In this codec, the rate may be controlled through a set of coding parameters, largely depending on the specific PC to code, notably its sparsity and homogeneity.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122749010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optimizing Compression Schemes for Parallel Sparse Tensor Algebra","authors":"Helen Xu, T. Schardl, Michael Pellauer, J. Emer","doi":"10.1109/DCC55655.2023.00084","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00084","url":null,"abstract":"This paper studies compression techniques for parallel in-memory sparse tensor algebra. Although one might hope that sufficiently simple compression schemes would generally improve performance by decreasing memory traffic when the computation is memory-bound, we find that applying existing simple compression schemes can lead to performance loss due to the additional computational overhead. To resolve this issue, we introduce a novel algorithm called byte-opt, an optimized version of the byte format from the Ligra + graph-processing framework [1] that saves space without sacrificing performance. The byte-opt format takes advantage of per-row structure to speed up decoding without changing the underlying representation from byte.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"143 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115980427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jan Østergaard, Christian Pedersen, Mo Zhou, N. D. Koeijer, M. Møller
{"title":"Multiple Description Audio Coding for Wireless Low-Frequency Sound Zones","authors":"Jan Østergaard, Christian Pedersen, Mo Zhou, N. D. Koeijer, M. Møller","doi":"10.1109/DCC55655.2023.00022","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00022","url":null,"abstract":"We present a joint design of sound zone control filters and robust audio coding for wireless low frequency sound zones. The audio signal is filtered using sound zone control filters and encoded using a multiple-description coder. The control filters and the multiple-description coder are combined in a nested loop. The inner loop performs filtering for sound zone control and generates multiple descriptions using oversampling and closed-loop prediction. The outer loop performs noise shaping and guarantees a trade-off between robustness and quality of the descriptions. A closed-form expression for the optimal sound-zone control filters are provided, and a simulation study demonstrates that even at moderate packet loss rates, a significant gain is possible compared to not using multiple descriptions.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133074450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Compressed unordered integer sequences with fast direct access","authors":"I. Zavadskyi","doi":"10.1109/DCC55655.2023.00053","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00053","url":null,"abstract":"A compressed representation of integer sequences is the key element of different data compression techniques. The variable-length Reverse Multi-Delimiter codes [1] provide a simple and space-efficient solution to the given problem, combining a good compression ratio with fast decoding. In this research, we investigate another property of RMD-codes - the ability of direct access to codewords in the encoded bitstream. If integers are sorted and the deltas between them are small enough, the problem of direct access is reduced to performing the select operation on a bitmap. However, RMD-codes allow us to address the more general problem of direct access to elements of an unordered integer sequence given in a compressed form. We developed the method of extracting and decoding a codeword from an RMD-bitstream in almost constant time. In text compression, the solution is highly space-saving as the RMD-code size is close to the entropy and extra data structures are tiny.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115650047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"CNN Quadtree Depth Decision Prediction for Block Partitioning in HEVC Intra-Mode","authors":"Iris Linck, A. T. Gómez, G. Alaghband","doi":"10.1109/DCC55655.2023.00054","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00054","url":null,"abstract":"High Efficiency Video Coding. (HEVC) reflects the new international standardization for digital video coding technology. HEVC achieves higher compression compared to its antecessor at the expense of dramatically increasing coding complexity due to the use of a recursive quadtree to partition every frame to various block sizes, a process called prediction mode. We propose three CNNs based on VGGNet, one CNN for each CU size of 64x64, 32x32, and 16x16, as shown in Figure 1, to predict the quadtree levels for the CU blocks of HEVC reducing its code complexity. The new CNNs simplify the original VGGNet in terms of number of convolutional layers while maintaining the original 3x3 filters. As our model is designed to recognize the quadtree structure of a block of pixels instead of image categories, a shallow version of the VGGNet combined with our CU partition datasets will provide fast and accurate results. The accuracy of the model can be further improved because the input CU size is consistent with the size of CU encoded by HEVC, that avoids losses in the CU texture features. Our CNN models learn from three customized datasets of CU blocks encoded in the specific QP of 32. In this way there is no need to introduce QP as a parameter in the loss function used in other works, and further increase accuracy. Given the success of this idea, in the future models will have separate training for each QP of 22, 27 and 37, respectively.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114824041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mixed-precision Deep Neural Network Quantization With Multiple Compression Rates","authors":"Xuanda Wang, Wen Fei, Wenrui Dai, Chenglin Li, Junni Zou, H. Xiong","doi":"10.1109/DCC55655.2023.00075","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00075","url":null,"abstract":"Quantizing one single deep neural network into multiple compression rates (precisions) has been recently considered for flexible deployments in real-world scenarios. In this paper, we propose a novel scheme that achieves progressive bit-width allocation and joint training to simultaneously optimize mixed-precision quantized networks under multiple compression rates. Specifically, we develop a progressive bit-width allocation with switchable quantization step size to enable mixed-precision quantization based on analytic sensitivity of network layers under multiple compression rates. Furthermore, we achieve joint training for quantized networks under different compression rates via knowledge distillation to exploit their correlations based on the shared network structure. Experimental results show that the proposed scheme outperforms AdaBits [1] in various networks on CIFAR-10 and ImageNet.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127442270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Semantically Adaptive JND Modeling with Object-wise Feature Characterization and Cross-object Interaction","authors":"Xia Wang, Haibing Yin, Tingyu Hu, Qing-hua Sheng","doi":"10.1109/DCC55655.2023.00072","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00072","url":null,"abstract":"This work proposed a spatio-temporal JND model based on semantic attention. Firstly, the principal semantic features affecting visual attention are extracted, including the semantic sensitivity, objective area and shape, central bias and contextual complexity, and the HVS responses of these four features are explored and quantified. Secondly, the semantic attention model is constructed by inscribing the attentional competition model, considering the interaction between different objects with limited perception resources. Finally, the obtained semantic attention weighting factor is combined with the basic spatial attention model to develop an improved transform domain JND model. Detailed performance results of different JND models are shown in Tab. 1. The simulation results validate that the proposed JND profile is highly consistent with HVS, with strong competitiveness among the state-of-the-art models.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"5105 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132891569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Permutation coding using divide-and-conquer strategy","authors":"Kun Tu, D. Puchala","doi":"10.1109/DCC55655.2023.00046","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00046","url":null,"abstract":"In computer science permutations are used, e.g., in the tasks of pattern searching, duplicate documents detection and data compression [1], [2]. For this reason the reduction of redundancy leading to succinct representation of permutations is of great importance. In this paper, we introduce a novel method for succinct representation of permutations where the average number of bits per element required to encode permutations is $log_{2}n-1.269$, which is close to the theoretic limit. Furthermore, it is possible to formulate precise expressions for the average value, lower, and upper bounds to the number of bits required by the method. Let n be an integer power of 2. Then the proposed method can be described as follows: (i) the method follows the ‘‘divide-and-conquer’’ strategy and at each stage a considered permutation is divided into two equal halves (bins), (ii) binary encoding is used to describe elements-to-bins assignment (’ 0’-first, ‘l’-second bin), (iii) depending on a permutation some bits can be omitted, which leads to succinct representation. For instance, let $pi_{2}=(0,2,1,3,7,6,4,5)$. We start with the identity permutation $pi_{1}=(0,1,2,3,4,5,6,7)$. At the first stage $pi_{1}$ is split between two bins in relation to $pi_{2}$ as $pi_{1}=(0,1,2,3|4,5,6,7)$ which is encoded with bits ‘0000’. At the second stage we repeat the same operations leading to $pi_{1}=(0,2|1,3|6,7|4,5)$, and formulate the coding bits ‘01011’ Finally, at the last stage, we get $pi_{1}=pi_{2}=(0|2|1|3|7|6|4|5)$ encoded as ‘0010’. The concatenated bits give the unique code $C=0000010110010$ for $pi_{2}$. The lower and upper bounds for the length of codes $displaystyle frac{1}{n}|C|$ are $G^{min}(n)=displaystyle frac{1}{2}log_{2}n$ and $G^{max}left(nright)=displaystyle log_{2}n-left(1-frac{1}{n}right)$. The average number of bits per element required to encode permutations can be calculated as:","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131719652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dan Wang, Jin Wang, Yunhui Shi, Nam Ling, Baocai Yin
{"title":"Point Cloud Geometry Compression via Density-Constrained Adaptive Graph Convolution","authors":"Dan Wang, Jin Wang, Yunhui Shi, Nam Ling, Baocai Yin","doi":"10.1109/DCC55655.2023.00076","DOIUrl":"https://doi.org/10.1109/DCC55655.2023.00076","url":null,"abstract":"Recently, point-based point cloud geometry compression has attracted great attention due to its superior performance at low bit rates. However, lacking an efficient way to represent the local geometric correlation well, most existing methods [1, 2, 3] can hardly extract fine local features accurately. Thus it’s difficult for them to obtain high-quality reconstruction of local geometry of point clouds.","PeriodicalId":209029,"journal":{"name":"2023 Data Compression Conference (DCC)","volume":"219 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134201067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}