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Sunil Prasad Jaiswal

Bio: Sunil Prasad Jaiswal is an academic researcher from Hong Kong University of Science and Technology. The author has contributed to research in topics: Interpolation & Demosaicing. The author has an hindex of 11, co-authored 38 publications receiving 289 citations. Previous affiliations of Sunil Prasad Jaiswal include LNM Institute of Information Technology.

Papers
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Journal ArticleDOI
TL;DR: A new reduced-reference IQA algorithm for SC images is proposed based upon a more perceptually relevant prediction model and distortion categorization, which overcomes problems with existing free-energy-principle-based predictors and achieves better performance than the full- reference IQA metrics specifically designed for the 3-D synthesized views.
Abstract: In this paper, we address problems associated with free-energy-principle-based image quality assessment (IQA) algorithms for objectively assessing the quality of Screen Content (SC) and three-dimensional (3-D) synthesized images and also propose a very fast and efficient IQA algorithm to address these issues. These algorithms separate an image into predicted and disorder residual parts and assume disorder residual part does not contribute much to the overall perceptual quality. These algorithms fail for quality estimation of SC images as information of textual regions in SC images are largely separated into the disorder residual part and less information in the predicted part and subsequently, given a negligible emphasis. However, this is in contrast with the characteristics of human vision. Since our eyes are well trained to detect text in daily life. So, our human vision has prior information about text regions and can sense small distortions in these regions. In this paper, we proposed a new reduced-reference IQA algorithm for SC images based upon a more perceptually relevant prediction model and distortion categorization, which overcomes problems with existing free-energy-principle-based predictors. From experiments, it is validated that the proposed model has a better capability of efficiently estimating the quality of SC images as compared to the recently developed reduced-reference IQA algorithms. We also applied the proposed algorithm to judge the quality of 3-D synthesized images and observed that it even achieves better performance than the full-reference IQA metrics specifically designed for the 3-D synthesized views.

40 citations

Journal ArticleDOI
TL;DR: This paper proposes an adaptive spectral-correlation-based demosaicking (ASCD) algorithm that uses a novel anti-aliasing filter to suppress these interferences among the various color-difference spectra, and then integrates it with an intra-prediction scheme to generate a more accurate prediction for the reconstructed image.
Abstract: Color filter array (CFA) interpolation, or three-band demosaicking, is a process of interpolating the missing color samples in each band to reconstruct a full color image. In this paper, we are concerned with the challenging problem of multispectral demosaicking, where each band is significantly undersampled due to the increment in the number of bands. Specifically, we demonstrate a frequency-domain analysis of the subsampled color-difference signal and observe that the conventional assumption of highly correlated spectral bands for estimating undersampled components is not precise. Instead, such a spectral correlation assumption is image dependent and rests on the aliasing interferences among the various color-difference spectra. To address this problem, we propose an adaptive spectral-correlation-based demosaicking (ASCD) algorithm that uses a novel anti-aliasing filter to suppress these interferences, and we then integrate it with an intra-prediction scheme to generate a more accurate prediction for the reconstructed image. Our ASCD is computationally very simple, and exploits the spectral correlation property much more effectively than the existing algorithms. Experimental results conducted on two data sets for multispectral demosaicking and one data set for CFA demosaicking demonstrate that the proposed ASCD outperforms the state-of-the-art algorithms.

36 citations

Proceedings ArticleDOI
01 Oct 2014
TL;DR: This paper efficiently analyzes the relationships of intra and inter-color correlation among the channels and proposes a scheme that exploits the correlation between different color channels much effectively than the existing algorithms.
Abstract: Image demosaicking or color filter array interpolation is a process of interpolating missing color samples to reconstruct a full color image. In general, existing algorithms assume that the high frequency components such as edges, texture etc. of different color channels are similar and thus take an advantage of it to estimate the missing samples. In this paper, we efficiently analyze the relationships of intra and inter-color correlation among the channels and observe that such assumption fails in most cases. In view of this observation, we propose a scheme that exploits the correlation between different color channels much effectively than the existing algorithms. Experimental results demonstrate that the proposed algorithm outperforms the existing methods both in terms of Peak Signal to Noise Ratio (PSNR) and visual perception.

28 citations

Proceedings ArticleDOI
26 Mar 2019
TL;DR: An encoding approach based on Convolutional Neural Networks is explored to partly substitute classical heuristics-based encoder speed-ups by a systematic and automatic process, which allows controlling the trade-off between complexity and coding gains, in intra slices, with one single parameter.
Abstract: This paper provides a technical overview of a deep-learning-based encoder method aiming at optimizing next generation hybrid video encoders for driving the block partitioning in intra slices. An encoding approach based on Convolutional Neural Networks is explored to partly substitute classical heuristics-based encoder speed-ups by a systematic and automatic process. The solution allows controlling the trade-off between complexity and coding gains, in intra slices, with one single parameter. This algorithm was proposed at the Call for Proposals of the Joint Video Exploration Team (JVET) on video compression with capability beyond HEVC. In All Intra configuration, for a given allowed topology of splits, a speed-up of ×2 is obtained without BD-rate loss, or a speed-up above ×4 with a loss below 1% in BD-rate.

24 citations

Proceedings ArticleDOI
01 Sep 2013
TL;DR: A new reversible watermarking algorithm based on additive prediction-error expansion which can recover original image after extracting the hidden data is proposed and has a better embedding capacity and also gives better Peak Signal to Noise Ratio (PSNR) as compared to state-of-the-art reversible watermarked schemes.
Abstract: In this paper, we propose a new reversible watermarking algorithm based on additive prediction-error expansion which can recover original image after extracting the hidden data. Embedding capacity of such algorithms depend on the prediction accuracy of the predictor. We observed that the performance of a predictor based on full context prediction is preciser as compared to that of partial context prediction. In view of this observation, we propose an efficient adaptive prediction (EAP) method based on full context, that exploits local characteristics of neighboring pixels much effectively than other prediction methods reported in literature. Experimental results demonstrate that the proposed algorithm has a better embedding capacity and also gives better Peak Signal to Noise Ratio (PSNR) as compared to state-of-the-art reversible watermarking schemes.

24 citations


Cited by
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Journal ArticleDOI
01 Sep 1945-Nature
TL;DR: This text-book of pharmacognosy has grown from a laboratory manual intended for use in practical classes, and now comprises the requirements for the Chemist and Druggist Qualifying Examination of the Pharmaceutical Society of Great Britain.
Abstract: THIS text-book of pharmacognosy has already found wide recognition among teachers and students of pharmacy. Its subject matter has grown from a laboratory manual intended for use in practical classes, and now comprises the requirements for the Chemist and Druggist Qualifying Examination of the Pharmaceutical Society of Great Britain. A Textbook of Pharmacognosy By T. C. Denston. Fourth edition. Pp. xviii + 594. (London: Sir Isaac Pitman and Sons, Ltd., 1945.) 27s. 6d. net.

701 citations

Proceedings ArticleDOI
05 Aug 2017
TL;DR: The key advantage of the framework is that both photo-consistency as well geometric relations of the surface structure can be directly learned for the purpose of multiview stereopsis in an end-to-end fashion.
Abstract: This paper proposes an end-to-end learning framework for multiview stereopsis. We term the network SurfaceNet. It takes a set of images and their corresponding camera parameters as input and directly infers the 3D model. The key advantage of the framework is that both photo-consistency as well geometric relations of the surface structure can be directly learned for the purpose of multiview stereopsis in an end-to-end fashion. SurfaceNet is a fully 3D convolutional network which is achieved by encoding the camera parameters together with the images in a 3D voxel representation. We evaluate SurfaceNet on the large-scale DTU benchmark.

379 citations

Journal ArticleDOI
TL;DR: This survey provides a general overview of classical algorithms and recent progresses in the field of perceptual image quality assessment and describes the performances of the state-of-the-art quality measures for visual signals.
Abstract: Perceptual quality assessmentplays a vital role in the visual communication systems owing to theexistence of quality degradations introduced in various stages of visual signalacquisition, compression, transmission and display.Quality assessment for visual signals can be performed subjectively andobjectively, and objective quality assessment is usually preferred owing to itshigh efficiency and easy deployment. A large number of subjective andobjective visual quality assessment studies have been conducted during recent years.In this survey, we give an up-to-date and comprehensivereview of these studies.Specifically, the frequently used subjective image quality assessment databases are firstreviewed, as they serve as the validation set for the objective measures.Second, the objective image quality assessment measures are classified and reviewed according to the applications and the methodologies utilized in the quality measures.Third, the performances of the state-of-the-artquality measures for visual signals are compared with an introduction of theevaluation protocols.This survey provides a general overview of classical algorithms andrecent progresses in the field of perceptual image quality assessment.

281 citations

Proceedings ArticleDOI
TL;DR: In this article, the authors propose an end-to-end learning framework for multiview stereopsis, which takes a set of images and their corresponding camera parameters as input and directly infers the 3D model.
Abstract: This paper proposes an end-to-end learning framework for multiview stereopsis. We term the network SurfaceNet. It takes a set of images and their corresponding camera parameters as input and directly infers the 3D model. The key advantage of the framework is that both photo-consistency as well geometric relations of the surface structure can be directly learned for the purpose of multiview stereopsis in an end-to-end fashion. SurfaceNet is a fully 3D convolutional network which is achieved by encoding the camera parameters together with the images in a 3D voxel representation. We evaluate SurfaceNet on the large-scale DTU benchmark.

141 citations

01 Jan 2016
TL;DR: Thank you for downloading exploring artificial intelligence in the new millennium, instead of reading a good book with a cup of coffee in the afternoon, instead they are facing with some infectious virus inside their computer.
Abstract: Thank you for downloading exploring artificial intelligence in the new millennium. Maybe you have knowledge that, people have search hundreds times for their chosen novels like this exploring artificial intelligence in the new millennium, but end up in infectious downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they are facing with some infectious virus inside their computer.

137 citations