1. A method for estimating a distance between a first target and a second target in an image, the method to be implemented using a distance estimation system that includes a processor module, an image capturing module for capturing the image, the image capturing module including a lens and an image sensor, the method comprising: a) generating, by the processor module, an image depth map associated with the image; b) generating, by the processor module, first position information associated with a first position which corresponds to the first target in the image, and second position information associated with a second position which corresponds to the second target in the image; and c) computing, by the processor module, an estimate of a distance between the first target and the second target based on at least the image depth map, the first position information and the second position information, wherein computing the estimate of a distance between the first target and the second target further includes: c-1) estimating, by the processor module, a first target distance between the first target and the lens based on the first position information, the image depth map, a focus length of the lens for capturing the image, and a pixel size of the image sensor; and c-2) computing, by the processor module, the estimate of the distance between the first target and the second target, based on at least the first target distance, the first position information, the second position information, and the focus length of the lens.