{"title":"Adaptive sampling with Renyi entropy in Monte Carlo path tracing","authors":"Qing Xu, Ruijuan Hu, Lianping Xing, Yuan Xu","doi":"10.1109/ISSPIT.2005.1577198","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577198","url":null,"abstract":"Adaptive sampling is an interesting tool to lower noise, which is one of the main problems of Monte Carlo global illumination algorithms such as the famous and baseline Monte Carlo path tracing. The classic information measure, namely, Shannon entropy has been applied successfully for adaptive sampling in Monte Carlo path tracing. In this paper we investigate the generalized Renyi entropy to establish the refinement criteria to guide both pixel super sampling and pixel subdivision adaptively. Implementation results show that the adaptive sampling based on Renyi entropy outperforms the counterpart based on Shannon entropy consistently","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129249001","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":"Budgeted region sampling (BeeRS): do not separate sampling from warm-up, and then spend wisely your simulation budget","authors":"D. G. Pérez, H. Berry, O. Temam","doi":"10.1109/ISSPIT.2005.1577060","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577060","url":null,"abstract":"While the recent surge of research articles on sampling started with rather large sample sizes, it has later shifted to very small intervals, and it is now converging to intermediate sizes, and even to varying sizes. With 100M samples, warm-up is not an issue, at least with current cache sizes. However, with significantly smaller samples, warm-up becomes critical, especially when the sampling target accuracy is of the order of a few percent. However, in most sampling research works, warm-up has largely been treated as a separate issue. In this article, we advocate for an integrated approach at (simulator-based) warm-up and sampling. Instead of separating warm-up and sampling, we take exactly the opposite approach, provide a common instruction budget for warm-up and sampling, and we attempt to spend it as wisely as possible on either one. This budget and integrated approach at warm-up and sampling achieves an average CPI error of 1.68% on the 26 Spec benchmarks with an average sampling size of 288 millions instructions, and at the same time, it relieves the user from any delicate decision such as setting the sampling or warm-up sizes, thanks to the integrated warm-up+sampling and the region partitioning approaches","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127201681","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":"A scalable security architecture enabling coalition formation between autonomous domains","authors":"P. Belsis, S. Gritzalis, S. Katsikas","doi":"10.1109/ISSPIT.2005.1577158","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577158","url":null,"abstract":"Coalitions between autonomous domains are often formed in real life scenarios in order to enable access permissions to shared objects on grounds of bilateral resource-sharing agreements. The dynamic nature of coalitions poses new challenges relative to security management and joint administration of resources; therefore we distinguish a need for reconciliation and extension support to single-domain oriented security models, so as to incorporate location, time and context based related parameters in their role definition schemes. In this paper, we introduce a robust and scalable solution that enables the realization of coalition formation in a multi-domain policy ruled environment","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127341260","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":"Permuting and lifting wavelet coding for arbitrarily-shaped data with expanded nodes","authors":"Atsushi Honda, A. Kawanaka","doi":"10.1109/ISSPIT.2005.1577109","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577109","url":null,"abstract":"A novel wavelet coding scheme for 2-dimensional data which are defined on the arbitrarily shaped regions and are including the expanded nodes is proposed. A polygonal mesh coding method has been proposed, which has used the assignment procedure of the vertices constructing the polygonal mesh to nodes on 2-D regular mesh. In the 2-D structuring procedure a vertex are assigned to one or several nodes on the regular mesh plane for structuring a polygonal mesh with complex connectivity. And the structured geometry data have arbitrarily-shape on the 2-D regular mesh plane and are including the nodes which are connected to adjacent nodes but are not assigned the geometry. These nodes are called expanded nodes, and the nodes on which the geometry data were assigned are called representative node. In this paper we apply a lifting wavelet transform with the permuting process (PL-WT) for an expanded node at even locations and the neighboring representative node to reduce the correlations among representative nodes separated by the continuous expanded nodes. Experimental results for the 3-D model with complex connectivity show the proposed scheme gives better coding performance compared to the conventional scheme using SA-DWT and TAGC scheme adopted in MPEG-4","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131362189","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":"Improved single PARAFAC decomposition based blind MIMO system estimation","authors":"Yuanning Yu, A. Petropulu","doi":"10.1109/ISSPIT.2005.1577078","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577078","url":null,"abstract":"We consider the problem of frequency domain identification of a multiple-input multiple-output (MIMO) system driven by white, mutually independent unobservable inputs. In particular, we improve upon a method recently proposed by the authors that uses PARAFAC decomposition of a tensor that is formed based on higher-order statistics of the system output. The approach of Y. Yu and A.P. Petropulu, 2005, utilizes only one slice of the output tensor to recover one row of the system response matrix. We proposed an approach that fully exploits the information in the output tensor, and as a result achieves lower error values. The proposed modification renders the method applicable to systems with more inputs than outputs","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115689944","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":"Low-complexity initialization of adaptive equalizers using approximate channel inverse","authors":"Gang Wang, R. Kraemer","doi":"10.1109/ISSPIT.2005.1577182","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577182","url":null,"abstract":"In this paper, a low-complexity approximate channel inverse initialization scheme for blind equalization is proposed. The underlying idea is that the inverse of minimum phase finite impulse response (FIR) channels can be well approximated by inverting the most significant paths of the estimated channel impulse response (CIR). The parameters of the inverse of the truncated channel can be expressed in closed-form expressions in terms of the original CIR and can be used to initialize adaptive equalizers. By applying time-reversal method, the proposed initialization scheme can also be applied for equalization of maximum phase channels. Through extensive computer simulations, we show that channels that cannot be equalized by blind equalizers with the conventional single-spike initialization can now be well equalized with the proposed initialization","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115741166","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":"Real time Tarp-linear estimator for image noise reduction","authors":"U. Ali, S.A. Khan","doi":"10.1109/ISSPIT.2005.1577187","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577187","url":null,"abstract":"Many efficient wavelet domain estimation algorithms for noise reduction have been proposed in the literature. All of them are based on variance estimation, which require all wavelet coefficients to be saved in the memory thus causing constrains towards the development of real time system. Tarp filter has been used successfully for online/real-time variance estimation of the multilevel wavelets and has shown exceptional performance in image compression. This paper proposes the utilization of the Tarp filter for the estimation of wavelet coefficient variance without saving them in memory. The paper presents the results for Tarp-linear estimator (TLE) and compares it with simple linear estimator (LE). It is found that TLE, while having an advantage of memory free noise reduction method, compromise on SNR","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115878406","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":"PATFC: novel pseudorandom affine transformation-Based Feistel-network cipher","authors":"Y. Hasan, E. Mohammed","doi":"10.1109/ISSPIT.2005.1577203","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577203","url":null,"abstract":"In this paper, we present a novel symmetric-key block cipher, with variable block and key lengths, referred to as PATFC (pseudorandom affine transformation-based Feistel cipher), suitable for software and hardware implementations. PATFC adopts the 3-round Luby-Rackoff construction (a compact form of the Feistel network structure) for fusing pseudorandom functions of the plaintext partitions to obtain a pseudorandom permutation. PATFC mainly makes use of a novel keyed pseudorandom function (PRF) that is based on a pseudorandom affine transformation (constructed using a highly nonlinear pseudorandom sequence generator) followed by a data and key dependent encoding and simple hash processes. Extensive statistical tests of PATFC and its underlying PRF consistently demonstrated their competitive diffusion, confusion and pseudorandomness characteristics. Furthermore, PATFC is probably secure and not vulnerable to known/chosen/adaptive plaintext/cipher text attacks","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114574989","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":"Real-time 3D image visualization system for digital video on a single chip","authors":"N. Rafla","doi":"10.1109/ISSPIT.2005.1577220","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577220","url":null,"abstract":"Implementation of a real-time image visualization system on a reconfigurable chip (FPGA) is proposed. The system utilizes an innovative stereoscopic image capture, processing and visualization technique. Implementation is done as a two stage process. In the first stage, the stereo pair is captured using two image sensors. The captured images are then synchronized and sent to the second stage for fusion. A controller module is developed, designed, and placed on the FPGA for this purpose. The second stage is used for reconstruction and visualization of the 3D image. An innovative technique employing dual-processor architecture on the same single FPGA is developed for this purpose. The whole system is placed on a single PCB resulting in a fast processing time and the ability to view 3D video in real-time. The system is simulated, implemented, and tested on real images. Results show that this system is a low cost solution for efficient 3D video visualization using a single chip","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123836286","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":"Computing watermark capacity in images according to their quad tree","authors":"F. Yaghmaee, M. Jamzad","doi":"10.1109/ISSPIT.2005.1577205","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577205","url":null,"abstract":"Determining the capacity of watermark for images is a complex task. This capacity may be influenced by many factors such as the content of image and also the strength of watermark. In some recent works the image content has been considered for calculation of watermark capacity. One such approach is to use the noise visibility function (NVF) introduced in (Voloshynovsky, et al., 1999). In this paper we introduced a new method for finding NVF according to the quad tree representation of image instead of using pixel neighborhood data. Our experimental results showed that the depth of a pixel in image quad tree represents much information about the pixel and its maximum allowable distortion compared to pixel neighborhood data as used by the existing NVF computing method. Our method for determining NVF, gave similar results for image capacity compared to the approach based on original NVF calculation as given in (F. Zhang and H. Zhang, June 2004)","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"66 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120929092","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}