Sriram Sethuraman

Bio: Sriram Sethuraman is an academic researcher from Sarnoff Corporation. The author has contributed to research in topics: Motion estimation & Computer science. The author has an hindex of 17, co-authored 29 publications receiving 1405 citations. Previous affiliations of Sriram Sethuraman include Carnegie Mellon University & LG Electronics.

Compression and transmission of depth maps for image-based rendering

Abstract: We consider applications using depth-based image-based rendering (IBR), where the synthesis of arbitrary views occur at a remote location, necessitating the compression and transmission of depth maps. Traditional image compression has been designed to provide maximum perceived visual quality, and a direct application is sub-optimal for depth-map compression, since depth-maps are not directly viewed. In other words, the sensitivity of the rendering error depends on the image content as well as on the depth map, we propose two improvements to take this into account. Firstly, we consider region-of-interest (ROI) coding, where we identify those regions of the image where accurate depth is most crucial. Secondly, we reshape the dynamic range of the depth map. Our experiments show a significant improvement in coding gain (1.1 dB) and rendering quality when we integrated these two improvements into a standard JPEG-2000 coder.

Method and apparatus for encoding video information

Abstract: A method and apparatus for encoding, illustratively, a video information stream to produce an encoded information stream according to a group of frames (GOF) information structure where the GOF structure and, optionally, a bit budget are modified in response to, respectively, information discontinuities and the presence of redundant information in the video information stream (due to, e.g., 3:2 pull-down processing).

Latency-based statistical multiplexing

Abstract: When two or more different video streams a e compressed for concurrent transmission of multiple compressed video bitstreams over a single shared communication channel, control over both (1) the transmission of data over the shared channel and (2) the compression processing that generates the bitstreams is exercised taking into account the differing levels of latency required for the corresponding video applications. For example, interactive video games typically require lower latency than other video applications such as video streaming, web browsing, and electronic mail. A multiplexer and traffic controller takes these differing latency requirements, along with bandwidth and image fidelity requirements, into account when controlling both traffic flow and compression processing. In addition, an off-line profiling tool analyzes typical video applications off-line in order to generate profiles of different types of video applications that are then accessed in real-time by a call admission manager responsible to controlling the admission of new video application sessions as well as the assignment of admitted applications to specific available video encoders, which themselves may differ in video compression processing power as well as in the degree to which they allow external processors (like the multiplexer and traffic controller) to control their internal compression processing.

Method and apparatus for region-based allocation of processing resources and control of input image formation

Abstract: Apparatus and method for classifying regions of an image, based on the relative “importance” of the various areas and to adaptively use the importance information to allocate processing resources and input image formation.

Intra-frame quantizer selection for video compression

Abstract: An image is divided into one or more (e.g., foreground) regions of interest wiht transition regions defined between each region of interest and the relatively least-important (e.g., background) region. Each region is encoded using a single selected quantization level, where quantizer values can differ between different regions. In general, in order to optimize video quality while still meeting target bit allocations, the quantizer assigned to a region of interest is preferably lower than the quantizer assigned to the corresponding transition region, which is itself preferably lower than the quantizer assigned to the background region. The present invention can be implemented iteratively to adjust the quantizer values as needed to meet the frame's specified bit target. The present invention can also be implemented using a non-iterative scheme that can be more easily implemented in real time. The present invention enables a video compression algorithm to meet a frame-level bit target, while ensuring spatial and temporal smoothness in frame quality, thus resulting in improved visual perception during playback.

Capturing and processing of images using monolithic camera array with heterogeneous imagers

Abstract: Systems and methods for implementing array cameras configured to perform super- resolution processing to generate higher resolution super-resolved images using a plurality of captured images and lens stack arrays that can be utilized in array cameras are disclosed. Lens stack arrays in accordance with many embodiments of the invention include lens elements formed on substrates separated by spacers, where the lens elements, substrates and spacers are configured to form a plurality of optical channels, at least one aperture located within each optical channel, at least one spectral filter located within each optical channel, where each spectral filter is configured to pass a specific spectral band of light, and light blocking materials located within the lens stack array to optically isolate the optical channels.

Advertising management system for digital video streams

Abstract: A system for managing advertisements in a digital video environment, including methods for selecting suitable advertising based on subscriber profiles, and substituting advertisements in a program stream. The Ad management System (100) of the present invention manages the sales and insertion of digital video ads in cable tv, switched digital video and streaming internet based environments.

Modular intelligent transportation system

Abstract: A modular intelligent transportation system, comprising an environmentally protected enclosure, a system communications bus, a processor module, communicating with said bus, having a image data input and an audio input, the processor module analyzing the image data and/or audio input for data patterns represented therein, having at least one available option slot, a power supply, and a communication link for external communications, in which at least one available option slot can be occupied by a wireless local area network access point, having a communications path between said communications link and said wireless access point, or other modular components.

Advertisement filtering and storage for targeted advertisement systems

Abstract: An advertisement storage and filtering system for selectively identifying targeted advertisements to be stored in the memory of the STB. This storing of the selected advertisements can be accomplished in a number of ways. In one embodiment, the advertisements, in real-time and as they are received at the STB, are processed by the STB and only those advertisements with the appropriate characteristics are stored on the hard drive (HD). This may require some buffering of the advertisements in the STB memory as the STB processes and determines whether or not to store the advertisement. The information required to determine whether or not to store the advertisement could also be sent in advance, e.g., as a data service in an advertisement channel. Alternatively, the STB may store incoming advertisements in a memory temporarily and subsequently determine whether or not to retain the stored advertisements.

A survey of perceptual evaluations and requirements of three-dimensional TV

Abstract: A high-quality three-dimensional (3-D) broadcast service (3-D TV) is becoming increasingly feasible based on various recent technological developments combined with an enhanced understanding of 3-D perception and human factors issues surrounding 3-D TV. In this paper, 3-D technology and perceptually relevant issues, in particular 3-D image quality and visual comfort, in relation to 3-D TV systems are reviewed. The focus is on near-term displays for broadcast-style single- and multiple-viewer systems. We discuss how an image quality model for conventional two-dimensional images needs to be modified to be suitable for image quality research for 3-D TV. In this respect, studies are reviewed that have focused on the relationship between subjective attributes of 3-D image quality and physical system parameters that induce them (e.g., parameter choices in image acquisition, compression, and display). In particular, artifacts that may arise in 3-D TV systems are addressed, such as keystone distortion, depth-plane curvature, puppet theater effect, cross talk, cardboard effect, shear distortion, picket-fence effect, and image flipping. In conclusion, we summarize the perceptual requirements for 3-D TV that can be extracted from the literature and address issues that require further investigation in order for 3-D TV to be a success.