Hardware acceleration of the Integer Karhunen-Loève Transform algorithm for satellite image compression

Abstract

The use of the Integer Karhunen-Loeve Transform (Integer KLT) for spectral decorrelation in lossless compression of hyperspectral satellite images results in improved performance. However, the Integer KLT algorithm consists of sequential processes, which are computationally intensive, such as the covariance and eigenvector evaluations, matrix factorisation and lifting. These processes slow down the overall computation of the Integer KLT transform significantly. The acceleration of these processes within the context of limited power and hardware budgets is the main objective of this paper. The computations of each of these processes are investigated thoroughly by breaking them down into primitive arithmetic operations. Subsequently, a comprehensive analysis of these computations is presented to inspect the possibility and feasibility of different hardware mappingoptions. The proposed designs are implemented on a System-on-a-Chip platform, which incorporates a 32-bit hardwired microcontroller and a co-processing unit built within a field programmable gate array fabric. A novel architecture is proposed offering accelerated processing and low power consumption. The proposed solution is not only suitable for space applications, but also for different mobile and medical applications.