Clipping data values in a data processing system

摘要

A clipping and quantization technique is described for producing clipped numbers in a range of 0 to N-1 (from unclipped numbers in a range of -0.5N to (1.5N-1)), where N is 2m and m is the bit length of the desired clipped and quantized number. The most significant bit of the unclipped data value indicates whether an overflow of the permitted range has occurred and that clipping is required. The next most significant bit (m-1th) indicates which saturated value should be adopted. These properties of the unclipped data value may be exploited to generate the desired clipped and quantized numbers using logical left shifting and conditionally executed saturating instructions executing upon a general purpose processor 24. The shifting operations performed to achieve saturation operation may simultaneously yield quantization.