An inventory control system for determining an inventory condition of objects stored in the system, the system comprising: at least one storage drawer, each storage drawer including a plurality of storage locations for storing objects; a data storage device storing reference data for each storage drawer, wherein the reference data includes, for each region of interest corresponding to each respective storage drawer, at least one of a reference image signature representing attributes of the region of interest when a stored object is present, and a reference image signature representing attributes of the region of interest when the stored object is not present; a data processor configured to: derive an image signature representing attributes of a region of interest corresponding to a drawer using a captured image of the drawer, the region of interest being a subset of the captured image; and determine an inventory condition of the drawer according to the stored reference data corresponding to the region of interest and the derived image signature representing attributes of the captured image of the region of interest, wherein the image signature is derived based on a pixel number distribution determined with respect to intensity, hue, and saturation of the image, wherein the pixel number distribution is determined based on accumulating hue and saturation values of the image, for pixels with intensity values between low and high threshold values, in bins of a 2D hue-saturation histogram, wherein the 2D hue-saturation histogram is examined based on pixel number distributions to find a bin with the most pixels, wherein bins adjacent to the bin with the most pixels are included until the pixel count of a bin falls below a predefined fraction of the pixel count in the peak bin, wherein an average intensity, hue and saturation of selected bins is calculated for generating the image signature. at least one storage drawer, each storage drawer including a plurality of storage locations for storing objects; a data storage device storing reference data for each storage drawer, wherein the reference data includes, for each region of interest corresponding to each respective storage drawer, at least one of a reference image signature representing attributes of the region of interest when a stored object is present, and a reference image signature representing attributes of the region of interest when the stored object is not present; a data processor configured to: derive an image signature representing attributes of a region of interest corresponding to a drawer using a captured image of the drawer, the region of interest being a subset of the captured image; and determine an inventory condition of the drawer according to the stored reference data corresponding to the region of interest and the derived image signature representing attributes of the captured image of the region of interest, wherein the image signature is derived based on a pixel number distribution determined with respect to intensity, hue, and saturation of the image, wherein the pixel number distribution is determined based on accumulating hue and saturation values of the image, for pixels with intensity values between low and high threshold values, in bins of a 2D hue-saturation histogram, wherein the 2D hue-saturation histogram is examined based on pixel number distributions to find a bin with the most pixels, wherein bins adjacent to the bin with the most pixels are included until the pixel count of a bin falls below a predefined fraction of the pixel count in the peak bin, wherein an average intensity, hue and saturation of selected bins is calculated for generating the image signature. derive an image signature representing attributes of a region of interest corresponding to a drawer using a captured image of the drawer, the region of interest being a subset of the captured image; and determine an inventory condition of the drawer according to the stored reference data corresponding to the region of interest and the derived image signature representing attributes of the captured image of the region of interest, wherein the image signature is derived based on a pixel number distribution determined with respect to intensity, hue, and saturation of the image, wherein the pixel number distribution is determined based on accumulating hue and saturation values of the image, for pixels with intensity values between low and high threshold values, in bins of a 2D hue-saturation histogram, wherein the 2D hue-saturation histogram is examined based on pixel number distributions to find a bin with the most pixels, wherein bins adjacent to the bin with the most pixels are included until the pixel count of a bin falls below a predefined fraction of the pixel count in the peak bin, wherein an average intensity, hue and saturation of selected bins is calculated for generating the image signature.