Acuity: Image Analysis for the Personal Computer

The analysis of images has traditionally been confined to the domain of the minicomputer (and larger). With the advent of technology such as the MC-680×0 it is now possible to analyse complex images on personal computers in reasonable time. The Acuity software package provides such a possibility for the measurement of the properties of objects in an image. The package, written entirely in C, consists of approximately 120 kB of code and provides image segmentation into the individual objects (automatic and/or interactive), measurement of object features, and measurement statistics. Automatic image segmentation is generally based upon histogram analysis with the possibility of pre-filtering. Interactive segmentation makes use of a mouse interface. After the image has been split into the individual objects, measurements are performed. The features fall into several categories: Position (2 measures), Size (2 measures), Shape (6 measures), Intensity (2 measures), and Texture (4 measures). The formulas used to compute the measures are based upon recent developments in digital-image measurement theory. A number of utilities are available to define an experiment (e.g., to choose which features need to be measured), to print a summary of the measured data, to print a limited set of descriptive statistics, or to format the output data (feature vectors) in a manner that is compatible with commercially available data analysis software (e.g., StatWorks™, MacSpin™, Excel™). The complete analysis of a 256 2 image that contains approximately 60 objects each with an approximate diameter of 25 pixels takes about 35 seconds. This is on a personal computer that uses a MC-68020 with a clock frequency of 16 MHz and a MC-68881 floating point co-processor.