SENSOR DATA PROCESSING

Apparatus for and a method of processing sensor data, the method including: using a sensor, measuring values of a parameter over a region of interest to produce an image of the region of interest, the image having a plurality of pixels; for each pixel, determining an orientation of a gradient of the parameter, at that pixel, using the measured parameter values; for each of a plurality of predetermined ranges of gradient orientation values, determining a number of pixels that have a gradient orientation value within that range; identifying the predetermined ranges that correspond to a number of pixels above a threshold value; and for each identified predetermined range, identifying as corresponding to a feature of an object, pixels that have gradient orientation values within that predetermined range.