Image Processing and virtual reality: Image Processing and virtual reality Submitted By P.Priyadharsini T.Yuvapiriyaa Abstract: Abstract Image processing in its broadest sense is an umbrella term for representing and analyzing of data in visual form. The image processing is the manipulation of numeric data contained in a digital image for the purpose of enhancing its visual appearance. Virtual reality (VR) is a term that applies to computer-simulated environments that can simulate places in the real world, as well as in imaginary worlds. Abstract: Abstract Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special stereoscopic displays . Thus one can manipulate the images to bring out bright or faint features, and you will "flip" images to look for changes in them and also make the people to know their today’s reality in the virtual space. Introduction: Introduction Image Processing is a technique to enhance raw images received from cameras/sensors placed on satellites, space probes and aircrafts or pictures taken in normal day-to-day life for various applications . Virtual reality is a form of human- computer interaction in which a real or imaginary environment is simulated and users interact with and manipulate that world. Methods of image processing: Methods of image processing There are two methods available in Image Processing. Analog Image Processing Digital Image Processing Analog Image Processing : Analog Image Processing Analog Image Processing refers to the alteration of image through electrical means. The most common example is the television image. Digital Image Processing In this case, digital computers are used to process the image. The image will be converted to digital form using a scanner – digitizer and then process it. Image Analysis: Image Analysis Image analysis is concerned with making quantitative measurements from an image to produce a description of it. Image analysis techniques require extraction of certain features that aid in the identification of the object. The following are some of the image analysis techniques. Image Compression. Image Classification. Image Segmentation. Image Restoration. Image Reconstruction from projections. Image Segmentation : Image Segmentation Image segmentation is the process that subdivides an image into its constituent parts or objects. The segmentation should stop when the objects of interest in an application have been isolated. e.g., in autonomous air-to-ground target acquisition, suppose our interest lies in identifying vehicles on a road, the first step is to segment the road from the image and then to segment the contents of the road down to potential vehicles. Classification : Classification Classification is the labeling of a pixel or a group of pixels based on its value. Classification is one of the most often used methods of information extraction. In Classification, usually multiple features are used for a set of pixels. Classification is of two types namely, Supervised classification. Unsupervised classification. Image Restoration: Image Restoration Image restoration refers to removal or minimization of degradations in an image. This includes de-blurring of images degraded by the limitations of a sensor or its environment, noise filtering and correction of geometric distortion or non-linearity due to sensors. Image Compression: Image Compression Compression is a very essential tool for archiving image data, image data transfer on the network etc. One of most popular compression techniques, JPEG (Joint Photographic Experts Group) uses Discrete Cosine Transformation (DCT) based compression technique. Currently wavelet based compression techniques are used for higher compression ratios with minimal loss of data. Image Reconstruction from projections.: Image Reconstruction from projections . Image reconstruction from projection is a special class of image restoration problems where a two- (or higher) dimensional object is reconstructed from several one-dimensional projections. Each projection is obtained by projecting a parallel X-ray (or other penetrating radiation) beam through the object. Planar projections are thus obtained by viewing the object from many different angles. Types Of Image Processing: Types Of Image Processing The following are the types of image processing Image to image transformations. Image to information transformations. Information to image transformations. Image to image transformations. : Image to image transformations. Enhancement (make image more useful, pleasing) Restoration Eg. Deblurring ,grid line removal Geometry (scaling ,sizing ,zooming ,morphing one object to another). Image to information transformations. : Image to information transformations. Image statistics(histograms) (Histogram is the fundamental tool for analysis and image processing). Image compression. Image analysis(image segmentation ,feature extraction, pattern recognition). Computer-aided detection and diagnosis(CAD) Information To Image Transformations: Information To Image Transformations Decompression of compressed image data. Reconstruction of image slices from CT or MRI raw data. Computer graphics ,animations and virtual reality(synthetic objects). What Is Virtual Reality: What Is Virtual Reality Virtual reality (VR) is a technology that allows people to enter and interact with three-dimensional computer graphics worlds. Another term for these worlds is virtual environments. When a person uses a virtual world the sensory information that is present in the real world is replaced by computer-generated information, which may be of sufficient fidelity to allow the person effectively to believe that they are in the virtual world. Hardware :
Hardware The is tracker which is capable of
its location in space and its orientation. A tracker is sometimes combined with a traditional computer input device, such as a mouse or a joystick. An attempt to provide a truly natural input device, the data is outfitted with sensors that can read the angle of each of the finger joints in the hand. Two views of the simulated world are generated, one for each eye, and a stereoscopic display device is used to show the correct view to each eye.
Computer desktop encyclopedia : Computer desktop encyclopedia An artificial reality that projects the user into a 3D space generated by the computer. A virtual reality system uses stereoscopic goggles that provide the 3D imagery and some sort of tracking device, which may be used by the goggles themselves for tracking head and body movement, or a "data glove" that tracks hand movements. The glove lets you point to and manipulate computer-generated objects displayed on tiny monitors inside the goggles. Serious Work or Entertainment : Serious Work or Entertainment Virtual reality (VR) can be used to create an illusion of reality or imagined reality and is used both for amusement as well as serious training. Flight trainee for training airplane pilots and astronauts were the first form of this technology, which provided a very realistic and very expensive simulation. Immersive Environments : Immersive Environments Immersive displays use multi-sided rooms that you walk into, and an "immersive theater" or "immersive wall" uses a large flat or curved screen that completely fills your peripheral vision. Desktop virtual reality (desktop VR) uses a computer to play games and view environments that you move around in, although they lack the 3D reality of true VR systems. Marketing dictionary :
Marketing dictionary Virtual reality had its beginnings in computer games where participants would wear special helmets and gloves and stand on special platforms that simulate the sights, sounds, and movements of
in a real environment. In marketing, virtual reality allows marketers to create
. For example, consumers can tour resort areas in a virtual reality setting before they book an actual trip to the resort, or prospective computer buyers can walk through the inside of a computer they are considering for purchase.
Advantages: Advantages In detecting damaged facilities based on the remote sensing images. It gives disabled people the opportunity to join in activities not usually available to them. Lightweight helmets and more powerful computers will take VR into ordinary homes. Applications: Applications Image Processing Medical Imaging. Non-destructive Evaluation. Forensic Studies. Virtual Reality Aircraft pilot training. Medical rehabilitation. Training for surgical procedures. Conclusion:
Conclusion Most image processing technique involve treating the image as a two-dimensional signal and applying standard signal-processing techniques to it .So image processing founds application in real world. Virtual reality has been heavily criticized for being an inefficient method for navigating non-geographical information. At present, the idea of ubiquitous computing(Refers to the use of computers in everyday life, including PDAs,
and other mobile devices) is very popular in user interface design, and this may be seen as a reaction against VR and its problems
References: References Digital Image Processing - A Remote Sensing Perspective, John R. Jenson, 3rd Edition, Prentice – Hall, 2003. Digital Image Processing - Kenneth R. Castleman, Prentice-Hall, 1996. Burdea, G. and P. Coffet (2003). Virtual Reality Technology, Second Edition . Wiley-IEEE Press. Goslin, M, and Morie, J. F., (1996). "Virtopia" Emotional experiences in Virtual Environments", Leonardo , vol. 29, no. 2, pp. 95–100.