Predicting conditional branch outcomes on a Sobel edge detecting filter

Multi-dimensional signal processing usually requires the high-speed performance obtained from instruction-level parallelism. The Sobel edge detector algorithm can be classified as a typical multi-dimensional signal processing application since it is applicable to images represented in a two-dimensional space. The kernel of such algorithm consists of a nested loop with embedded conditional branches, which are used to determine the existence of an edge. The hardware implementation of a Sobel algorithm may require either extra execution time due to pipeline stalls or resource redundancy in order to handle the branch. This paper shows a new architecture design, which establishes, in advance, the outcome of the conditional branches and allows the execution of the loop with an apparent one hundred percent prediction accuracy.