Depth map correction using lookup tables

A depth map correction apparatus comprising:

• a processor arranged to receive data comprising time of flight depth camera amplitude and phase measurements, the data having a number of dimensions;
• depth map computation logic arranged to compute an estimate of a distance of a surface from the camera using the measurements;
• depth map correction logic arranged to access a look up table of less than the number of dimensions, the look up table storing depth multi-path correction values;
• the depth map correction logic being arranged to correct the computed estimate of distance using a distance multipath correction value from the look up table.

A system for correction of multipath reflection in a depth map comprising;

• depth map computation logic arranged to estimate a distance of an object from the difference in phase between light transmitted from a light source and light detected by a receiver;
• and
• depth map correction logic arranged to:
• access a lookup table, the lookup table containing adjusted amplitude and phase measurements of a plurality of modulation frequencies and;
• access a side parameter comprising phase information;
• generate a distance correction from information stored in the lookup table and the phase information contained in the side parameter;
• and
• apply the distance correction to the estimated distance to generate a corrected distance for the object.