Papers by Kumareswaran Sarath
Circuits and Systems for Video …, Jan 1, 2006
… on circuits and Systems for video …, Jan 1, 2005
A robust error concealment scheme using data hiding which aims at achieving high perceptual quali... more A robust error concealment scheme using data hiding which aims at achieving high perceptual quality of images and video at the end-user despite channel losses is proposed. The scheme involves embedding a low-resolution version of each image or video frame into itself using spread-spectrum watermarking, extracting the embedded watermark from the received video frame, and using it as a reference for reconstruction of the parent image or frame, thus detecting and concealing the transmission errors. Dithering techniques have been used to obtain a binary watermark from the low-resolution version of the image/video frame. Multiple copies of the dithered watermark are embedded in frequencies in a specific range to make it more robust to channel errors. It is shown experimentally that, based on the frequency selection and scaling factor variation, a high-quality watermark can be extracted from a low-quality lossy received image/video frame. Furthermore, the proposed technique is compared to its two-part variant where the low-resolution version is encoded and transmitted as side information instead of embedding it. Simulation results show that the proposed concealment technique using data hiding outperforms existing approaches in improving the perceptual quality, especially in the case of higher loss probabilities.
SPIE Photonics East'99, Jan 1, 1999
Previous works on data hiding generally targeted on a specific tradeoff between capacity and robu... more Previous works on data hiding generally targeted on a specific tradeoff between capacity and robustness. This results in overestimation of the processing noise under some situations and/or underestimation under some other situations, hence limits the overall performance. In this paper, we propose a multi-level data hiding scheme which is able to convey secondary data in high rate when noise is not severe and can also convey some data reliably under heavy distortion. The proposed scheme is motivated by a two-category classification of embedding schemes and by a study on detection performance of spread spectrum watermarking. The multi-level data hiding has been successfully applied to both digital image and video, and can be used for applications such as copy control.
Image Processing, IEEE Transactions on, Jan 1, 2003
This paper applies the solutions to the fundamental issues addressed in Part I to specific design... more This paper applies the solutions to the fundamental issues addressed in Part I to specific design problems of embedding data in image and video. We apply multilevel embedding to allow the amount of embedded information that can be reliably extracted to be adaptive with respect to the actual noise conditions. When extending the multilevel embedding to video, we propose strategies for handling uneven embedding capacity from region to region within a frame as well as from frame to frame. We also embed control information to facilitate the accurate extraction of the user data payload and to combat such distortions as frame jitter. The proposed algorithm can be used for a variety of applications such as copy control, access control, robust annotation, and content-based authentication.
Image Processing, IEEE Transactions on, Jan 1, 2003
… and Systems for Video …, Jan 1, 2000
Digital data hiding is a technology being developed for multimedia services, where significant am... more Digital data hiding is a technology being developed for multimedia services, where significant amounts of secure data is invisibly hidden inside a host data source by the owner, for retrieval only by those authorized. The hidden data should be recoverable even after the host has undergone standard transformations, such as compression. In this paper, we present a source and channel coding framework for data hiding, allowing any tradeoff between the visibility of distortions introduced, the amount of data embedded, and the degree of robustness to noise. The secure data is source coded by vector quantization, and the indices obtained in the process are embedded in the host video using orthogonal transform domain vector perturbations. Transform coefficients of the host are grouped into vectors and perturbed using noise-resilient channel codes derived from multidimensional lattices. The perturbations are constrained by a maximum allowable mean-squared error that can be introduced in the host. Channel-optimized can be used for increased robustness to noise. The generic approach is readily adapted to make retrieval possible for applications where the original host is not available to the retriever. The secure data in our implementations are low spatial and temporal resolution video, and sampled speech, while the host data is QCIF video. The host video with the embedded data is H.263 compressed, before attempting retrieval of the hidden video and speech from the reconstructed video. The quality of the extracted video and speech is shown for varying compression ratios of the host video.
icip, Jan 1, 1997
We introduc ea scheme for hiding high bit-rate sup-plementary data, such as secondary video, into... more We introduc ea scheme for hiding high bit-rate sup-plementary data, such as secondary video, into a dig-ital video stream by directly modifying the pixels in the video frames. The technique requiresno sepa-rate channel or bit interle avingto transmit the ex-tra information. The ...
Image Processing, 1999. ICIP 99. …, Jan 1, 1999
We propose a video data embedding scheme in which the embedded signature data is reconstructed wi... more We propose a video data embedding scheme in which the embedded signature data is reconstructed without knowing the original host video. The proposed method enables high rate of data embedding and is robust to motion compensated coding, such as MPEG-2. Embedding is based on texture masking and utilizes a multi-dimensional lattice structure for encoding signature information. Signature data is embedded in individual video frames using the block DCT. The embedded frames are then MPEG-2 coded. At the receiver, both the host and signature images are recovered from the embedded bit stream. We present examples of embedding image and video in video.
SID Conference 14th Annual Symposium on Vehicle …, Jan 1, 2007
Light Blue Optics' holographic laser projection technology has significant c... more Light Blue Optics' holographic laser projection technology has significant competitive advantages compared to imaging and scanning projection technol ogy. This paper describes the system, its operation, and advantages. It is shown that the particular combina tion of benefits that LBO's technology offers provides comp elling and differentiating advantages for automotive head- up and instrument cluster displays.
Optics and Spectroscopy, Jan 1, 2009
... can be deposited on substrates by vacuum sputtering, they belong to the most promising record... more ... can be deposited on substrates by vacuum sputtering, they belong to the most promising recording media for fabricating aberration-free hologram opti-cal elements (hologram projectors) for excimer and extremely short-wavelength UV holographic projection photolithography ...
doi.ieeecomputersociety.org
... The second part is to develop software for producing 3D video contents to be display on the h... more ... The second part is to develop software for producing 3D video contents to be display on the holographic projector. To facilitate the ease of content development, my software is capable of parsing a standard VRML model, and ...
Wilkinson, TD and Cable, AJ and Buckley, E and Mash, P and Lawrence, NA and Crossland, WA (2004) ... more Wilkinson, TD and Cable, AJ and Buckley, E and Mash, P and Lawrence, NA and Crossland, WA (2004) Holographic projector based on a FLC over silicon microdisplay. In: International Conference on Liquid Crystals (ILCC), -7-2004 to --, Slovenia. ... Full text not available from this repository. ... CUED Publications database is powered by EPrints 3 which is developed by the School of Electronics and Computer Science at the University of Southampton. More information and software credits.
Proceedings of SPIE, Jan 1, 2010
With the advent of faster computers, higher resolution LC displays, and cheap lasers there has be... more With the advent of faster computers, higher resolution LC displays, and cheap lasers there has been a surge in interest in building video projection systems where a computer generated hologram (CGH) is calculated from the video image and displayed on a LC ...
Arxiv preprint arXiv:1006.0846, Jan 1, 2010
This research papers examines the new technology of Holographic Projections. It highlights the im... more This research papers examines the new technology of Holographic Projections. It highlights the importance and need of this technology and how it represents the new wave in the future of technology and communications, the different application of the technology, the fields of life it will dramatically affect including business, education, telecommunication and healthcare. The paper also discusses the future of holographic technology and how it will prevail in the coming years highlighting how it will also affect and reshape many other fields of life, technologies and businesses.
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Papers by Kumareswaran Sarath