Flatbed scanned pictures can be used for morphometrical image analysis. However, the commercial image processing tools are often too complicated for an elementary area measurement. We describe a simple image processing application PixArea (PA), containing an instructive ”green line” menu interface. The tumour area or regions of interest (ROI) can be calculated without microscopy-based image acquisition. The idea is to saturate the ROI with purple and the normal tissue with cyan. The remaining background is coloured white. The program computes the pixels every time the corresponding area in the picture is clicked with the mouse.