1. A method of filtering depth information, the method comprising: illuminating a scene with a modulated illumination light having a plurality of different modulation frequencies, the modulated illumination light reflecting from surfaces in the scene as modulated reflection light; receiving at each of a plurality of pixels the modulated reflection light; observing a phase difference between the modulated illumination light and the modulated reflection light at each of the plurality of pixels for each of the modulation frequencies; for each of the plurality of pixels and modulation frequencies, recognizing an edginess of that pixel corresponding to a relative difference between the phase difference of that pixel and phase differences of one or more neighboring pixels; and for each of the plurality of pixels and modulation frequencies, smoothing the phase difference of that pixel relative to phase differences of one or more neighboring pixels as a function of the edginess of that pixel such that greater edginess corresponds to less smoothing and lesser edginess corresponds to more smoothing.