Parallel Architectures And Computer Vision

Parallel Architectures and Computer Vision

The computer interpretation of visual images offers unlimited potential, with applications ranging from robotics and manufacturing to electronic sensors for aiding the blind. However, there is a huge gap between the promise of technology and what is actually possible now. In order to work effectively, computers will have to sense and analyze visual scenes in a fraction of a second, but currently it is not unusual to devote an hour of computer time to the analysis of a single image. Also, such images often have to be of highly stylized scenes to make any analysis possible. The only hope for the future lies in the use of massive parallel architectures, with perhaps thousands of processors cooperating on the task. Fortunately, the spectacular advances now being made in VLSI technology may allow such parallelism to be economically feasible. This book draws together the proceedings of a key workshop held in 1987. It presents the work of leading U.K. researchers in parallel architectures and computer vision from both industry and academia, providing a clear indication of the state of the art.

Pyramidal Architectures for Computer Vision

Computer vision deals with the problem of manipulating information contained in large quantities of sensory data, where raw data emerge from the transducing 6 7 sensors at rates between 10 to 10 pixels per second. Conventional general purpose computers are unable to achieve the computation rates required to op erate in real time or even in near real time, so massively parallel systems have been used since their conception in this important practical application area. The development of massively parallel computers was initially character ized by efforts to reach a speedup factor equal to the number of processing elements (linear scaling assumption). This behavior pattern can nearly be achieved only when there is a perfect match between the computational struc ture or data structure and the system architecture. The theory of hierarchical modular systems (HMSs) has shown that even a small number of hierarchical levels can sizably increase the effectiveness of very large systems. In fact, in the last decade several hierarchical architectures that support capabilities which can overcome performances gained with the assumption of linear scaling have been proposed. Of these architectures, the most commonly considered in com puter vision is the one based on a very large number of processing elements (PEs) embedded in a pyramidal structure. Pyramidal architectures supply the same image at different resolution lev els, thus ensuring the use of the most appropriate resolution for the operation, task, and image at hand.

Parallel Architectures and Computer Vision