1. A method for determining a volume of an item of food in an image captured by a camera of a wireless cellular device, the method comprising: selecting a pattern with known spatial characteristics from a display of a wireless cellular device; using an illuminator of said wireless cellular device to project the selected pattern onto an item of food for which a volume is intended to be estimated; using a camera of said wireless cellular device to capture multiple images of said item of food at different angles while said item is being illuminated by said projected pattern, a spatial distortion being introduced by a reflection of said pattern off a surface of said food item; measuring at least one distance to said food item using a distance measuring module of said wireless cellular device; inputting information about the food item using said wireless cellular device; estimating, based on said measured distances, a camera pose for each of said multiple images; identifying a sub-set of images with preferred camera poses, said sub-set comprising images in at least one top view perspective, at least two side view perspectives, and at least one oblique view perspective; calculating multiple depth maps where depth map d 1 (i,j) corresponds to said top view perspective, depth maps d 2 (i,j) and d 3 (i,j) correspond to said two side view perspectives respectively, and depth map d 4 (i,j) corresponds to said oblique view perspective, each of said depth maps being calculated based on depth distributions of a surface on which said food item lies by comparing spatial characteristics of reflections detected in each image to known spatial characteristics of said projected pattern such that spatial distortions introduced into said pattern reflections off said food item can be characterized at different locations on a surface of the food item, said characterizations being used to calculate said depth maps in each perspective; estimating a volume from each of said depth maps; aggregating said volumes estimated from each of said depth maps to obtain a final estimated volume for said food item; retrieving, from a memory of said wireless cellular device, a model which identifies a symmetry of said food item; using said retrieved model to refine said final estimated volume; and displaying said refined final estimated volume on a display of said wireless cellular device.