In this paper we present our recent research and development work for multicore computing of Line of Sight (LoS) on the Cell Broadband Engine (CBE) processors. LoS can be found in many applications where real-time high performance computing is required. We will describe an efficient LoS multi-core parallel computing algorithm, including the data partition and computation load allocation strategies to fully utilize the CBE's computational resources for efficient LoS viewshed parallel computing. In addition, we will also illustrate a successive fast transpose algorithm to prepare the input data for efficient Single-Instruction-Multiple-Data (SIMD) operations. Furthermore, we describe the data input and output (I/O) management scheme to reduce the (I/O) latency in Direct-Memory-Access (DMA) data fetching and storing operations. The performance evaluation of our LoS viewshed computing scheme over an area of interest (AOI) with more than 4.19 million points has shown that our parallel computing algorithm on CBE takes less than 25.5 ms, which is several orders of magnitude faster than the available commercial systems. © 2011 IEEE.