Multi-operand block-floating point arithmetic for image processing
A. Lipchin, I. Reyzin, Dimitri A. Lisin, Mahesh Saptharishi · 2010
We extend the application of block-floating point arrays to multi-operand algebraic expressions consisting of additions and multiplications. The proposed method enables automatic runtime calculation of binary shifts of array elements. The shifts are computed for all elementary operations in an expression using a dataflow graph. The method attempts to preserve accuracy across the entire expression while avoiding overflow. A variety of common computer vision and image processing operations can be efficiently realized in fixed-point processors using the proposed technique. It eliminates the need to hand-craft block-floating point implementations for each new operation or processor. The result is a reduction in development time and the likelihood of errors.