An Integrated Asynchronous Cellular Array to Do Parallel Image Reconstruction

We show in this paper how it is possible to reconstruct an image, in a very parallel way. using an asynchronous cellular array, with real-time performance. After introducing the image reconstruction problem, we present the main reconstruction techniques and the sequential algorithms. Then, we explain the manner to process these algorithms on a network. We describe this new integrated parallel architecture, its originalities, and the system performing the whole reconstruction. We present the efficiency of th i s parallel image reconstruction method. and the performance of the network. image section; we collect the rays after their passage through the object I l l . The set of data collected at each angular setting is called a projection. The ray intensity decreases with the quantity of material passed through. this ray attenuation is the line integral on its palh of the object density : attenuation = density. path The cross-section is divided in N little squares (the pixels), ai is the value of the ith pixel. Pk the ray sum of the kth ray (attenuation); we can write :