Salience makes objects pop-up from their surrounding and immediately attract our attention. A salient object in the visual domain would, e.g., be a red dot among white ones. We can sometimes intuitively say an object is more salient than the other, e.g., a moving red dot might be more salient than a static one.
Is there a way to quantify how salient an object is?
To narrow down the question a little, suppose you have a set of different output devices that can provide either visual or auditory cues (LEDs, loudspeakers, lamps, screens...) and they are near a target object you which to attract attention to. Ideally one would choose the output device that is closest to the target object to attract attention, but depending on the distance, the output device may not be as conspicuous. So at a given distance, I would like to know, which device will attract attention the most. The environment would be mostly static and well lit.