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Telepresence system provides interfaces to remotely teleoperate robot and execute hazardous task. These tasks are generally executed by human operator in master–slave mode. Telepresence interface provides a small haptic device to manipulate robot, stereoscopic view to see the environment and moreover force reflection capability. Bilateral master–slave tele-manipulation depends upon operator’s experience and agility to a large extent. In this article, we discuss the concept of 3D mouse and path-planning functionality for an autonomous stereo vision guided telerobotics system. These augmented reality functionalities will assist operator to perform pick and place operations more efficiently.

Image stitching algorithms construct a single composite high resolution image with a larger field of view using multiple low resolution images. Data wall systems combine the power of multiple graphics cards to provide large number of pixels. In this research work, we propose and implement scalable high resolution panorama composition on the data wall system using distributed rendering. We make use of a cross platform OpenGL library for real-time panorama composition. Our algorithm works for image sources with fixed relative positions. Initially, we employ an OpenCV image processing library for panorama calibration. Subsequently, these calibration results are utilized to generate a seamless panoramic image. We construct a high resolution 3×3 data wall system using commodity projectors. We achieve a seamless display with the help of geometric alignment of projector regions and edge blending in overlapping regions. Conventional display devices with their limited image resolution lose details provided by high resolution panorama because of data compression. We integrate panorama composition and the data wall system using distributed rendering. We distribute panorama composition to rendering workstations, which compute their respective screen space bounding regions and operate within it. It provides high resolution panorama with greater details on the data wall system.

In this research work, we propose and realize a real-time stereoscopic vision system for neurosurgery training using a surgical stereoscopic microscope. We connect a pair of high resolution IP cameras to a surgical microscope through a dual port microscope beam splitter and a pair of microscope video adaptors. We make use of the specifically designed chessboard calibration pattern and an open source OpenCV library for system calibration. We perform local calibration to align individual IP camera views with each other, whereas global calibration is carried out to line up local calibrated camera views parallel with the user defined reference coordinate system. We calibrate our stereoscopic system using a single input image of the calibration pattern. We perform real-time stereo image remapping for the comfortable stereoscopic vision using a GPU. A media server is developed and introduced in between the IP camera pair and viewer applications to support multiple stereo image streams as well as to provide one more layer of protection to IP cameras. We make use of a NVIDIA 3D Vision Pro system and a 3D ready 120Hz monitor for active stereoscopic vision. We utilize HDMI-1.4 frame packing for passive stereoscopic vision on a standard 3D-TV. We measure network latency of our stereoscopic system with and without using the media server application, which is within acceptable limits. Finally, we compare NVIDIA 3D Vision Pro based active stereoscopic vision and passive stereoscopic vision using a 3D-TV with their pros and cons.

In this work, we manipulate an industrial robot from a remote place through a Local Area Network using a force feedback enabled Phantom haptic device as a master, and a stereo vision system for viewing as well as for depth estimation. We propose and implement a stereo vision guided telerobotics system for autonomous pick and place operations. The robot gets the location of pick up from a pre-specified marker, whose position is determined by the stereo vision system. We make use of a pair of IP cameras as the stereo camera, a 3D enabled monitor for viewing stereo contents and an NVIDIA 3D Vision Pro system for managing our stereo vision system. We perform real-time stereo rectification of a stereo image stream for comfortable stereoscopic viewing. We design object markers to support stereo matching up to sub-pixel level. The coordinate systems of the robot and the stereoscopic system are transformed to a pre-defined world coordinate system using a planar chessboard calibration pattern. We evaluate accuracy and repeatability of our stereo vision system on the chessboard plane as well as within the working volume of the robot. Our stereoscopic system is highly accurate with errors less than 2mm along X and Y directions, and below 5mm along Z direction which is direction of viewing.

High resolution displays utilizing an array of commodity projectors are becoming popular approach(also called tiled displays) for visualizing high resolution content like scientific data-sets. These systems provide a relatively cheaper and flexible alternative to displays based on single high resolution monitor or projector. This approach inherently provides a method to create displays with resolution much higher than that possible by using a single high resolution display device. However, bezels in monitor based tiled displays obstruct the geometric continuity of the rendered content. In this paper, we describe the algorithms for geometric alignment of projection regions of an array of arbitrarily placed projectors and attenuation of projected intensities in the overlapping regions of multiple projectors using camera as a feedback device. Combination of these algorithms help us achieve a seamless high resolution display. We have observed improvements in fidelity of the rendered content by utilizing collinearity constraint in geometric alignment calculations. We also propose a novel technique based on cross-ratio invariant for utilizing full projection region of individual projectors which was limited by the size of features used for geometric alignment in the earlier approaches for planar displays. This also results in more imperceptible edge blending artifacts for same physical setup of projectors.

A visualization of large datasets requires ultra high resolution. Data wall systems provide large number of pixels by combining a power of multiple graphics cards. In this paper, we propose and realize an object oriented framework for the Message Passing Interface based parallel rendering. We introduce a GUI based viewer called the TiledRenderer, which is used for viewing pre-recorded high resolution animations as well as images on data walls. We identify a set of design patterns in a development of the TiledRenderer. We talk about benefits of using design patterns for extending our framework for adding the Real Time Streaming Protocol based IP camera support. We demonstrate that use of design patterns facilitates reusing the existing functionality and adding new functionality by providing new classes, rather than modifying the existing classes or functionality. We also discuss about a visualization of tsunami simulation data by using 6×6 data wall and the TiledRenderer.

In this paper, we propose and implement an object oriented framework for the GPU based image processing. Compute Unified Device Architecture i.e. the CUDA is a novel and promising GPU programming framework from the NVIDIA. The CUDA has been used to speedup many computationally intensive graphics as well as non graphics applications, but it requires more than just kernel programming. A pyramidal image blending algorithm is essential for a seamless panoramic mosaic. We introduce an object oriented framework for the CUDA based pyramidal image blending using software engineering principles and design patterns. We illustrate a set of design patterns, which assist in reusing an existing functionality. We show that use of design patterns facilitate extending existing functionality by adding new classes, rather than modifying an existing classes or functionality. We also talk about extending our framework for computation using the GPU texture memory. We talk about the framework's performance in terms of programming efforts and a speedup factor achieved.

Maze solving has direct applications like Robot path finding, emergency evacuation, and drug discovery. Traditional methods of maze solving treat the problem of maze as a directional graph by connecting the key nodes. Because of the directional graph treatment, which is applied on the simplified form of the original maze, the maze solving algorithms at present cannot be directly applied in the critical domains of emergency evacuation etc. The proposed method uses the original complex maze without simplifying and hence can be directly applied in any critical application related to path finding. Proposed approach solves the mazes in a fully automated mode by combining the techniques of image processing, computational geometry and computational fluid dynamics. Moreover the high amount of human intervention needed for generating graphs from mazes in the traditional algorithms is eliminated altogether.

Today we can have huge datasets resulting from computer simulations (FEA, CFD, physics, chemistry etc) and sensor measurements (medical, seismic and satellite). There is exponential growth in computational requirements in scientific research. Modern parallel computers and Grid are providing the required computational power for the simulation runs. The rich visualization is essential in interpreting the large, dynamic data generated from these simulation runs. The visualization process maps these datasets onto graphical representations and then generates the pixel representation. The large number of pixels shows the picture in greater details and interaction with it enables the greater insight on the part of user in understanding the data more quickly, picking out small anomalies that could turn out to be critical and make better decisions. However, the memory constraints in frame buffer, lack of the rendering power and the display resolution offered by even the most powerful graphics workstation makes the visualization of this magnitude difficult or impossible. This paper focuses on building an environment which render and drive over 47 millions of pixels, using the open source software framework. Our system’s display geometry is easy to configure and reconfigure, accommodates casually tiled displays and arbitrary display surfaces, and can be operational in a matter of minutes. In addition, the underlying distributed rendering architecture (chromium) is transparent to existing OpenGL applications, requiring no custom APIs or re-compilation of existing OpenGL executables. In short, we present a practical and flexible low-cost tiled display system that is simple to deploy and easy to operate. We also describe the software packages developed for such a system and its use to visualize data generated by computational simulations and applications requiring higher intrinsic display resolution and more display space.