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A <italic>fisheye</italic> lens is a very wide angle lens that shows places nearby in detail while also showing remote regions in successively less detail. This paper describes a system for viewing and browsing planar graphs using a software analog of a fisheye lens. We first show how to implement such a view using solely geometric transformations. We then(More)
Views rdphs with hundreds of vertices and cdgcs arc common in many application arca of computrr scirnce, such as network topology, VLSI circuits, arrd graph theory. There arc litrralty hundreds of algorithms for posidoning nodes to pn~ ducr an aesthetic and informative display [I]. However, once a layout is chosen, what is an cffrctive way to view and(More)
We propose the metaphor of rubber sheet stretching for viewing large and complex layouts within small display areas. Imagine the original 2D layout on a rubber sheet. Users can select and enlarge diierent areas of the sheet by holding and stretching it with a set of special tools called handles. As the user stretches an area, a greater level of detail is(More)
A combined DWT and DCT based watermarking technique with low frequency watermarking with weighted correction is proposed. DWT has excellent spatial localization, frequency spread and multi-resolution characteristics, which are similar to the theoretical models of the human visual system (HVS). DCT based watermarking techniques offer compression while DWT(More)
StretchTools is a set of tools for manipulating the screen space. The user interface uses the metaphor of stretching a rubber sheet. The basic tool in StretchTools is the handle. A handle is an one-dimensional rigid object of a xed orientation, either horizontal or vertical. As a handle is placed on the screen, engaged, and pulled, the screen expands on one(More)
The accompanying videotape demonstrates a system for viewing large graphs [2]. It's one of many possible implementations of a general framework for graphical fisheye views that we have developed. The graph in the video represents direct routes between major cities in the United States. An obvious way to see more detail about an area is to zoom into the(More)
We present an object-oriented data model. The data model represents all entities as objects. The system uses internally generated object identiiers for giving objects their unique identity. An object also has a state, and a behavior. Each object belongs to a class. The class deenes the structure of the object's state, and its behavior. Classes are organized(More)
The images on the preceeding page are views of a graph representing the Paris Metro system. The vertices in the graph are the stations, and the edges are the connections between stations. All images are screen dumps from the prototype system described in this paper. The upper-left image is a normal view of the Metro; the other images are fisheye views of(More)
We develop a model for active entities in software systems. An active entity, or simply an entity, is an active object with a private state and one or more independent threads of control. Entities communicate with each other by message passing. A collection of communicating entities constitute a concurrent and distributed system. We present a language for(More)
A bstract Debugging parallel and distributed programs is harder than debugging sequential programs. A number of debuggers have been developed to alleviate the problem of debugging parallel and distributed programs. But there is a lack of any uniform approach to debugging such systems and as a result each debugger is different. In this paper, first the(More)
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