Patent ID: 7358976

Claim:
A machine vision method comprising: sensing light energy associated with a scene, wherein the sensing step comprises measuring three primary color values, wherein the three primary color values are red, green, and blue, wherein the red value is denoted r, the green value denoted g, and the blue value denoted b; generating color image data representing at least a portion of the scene, wherein the data are arranged as pixels, and the data for a given pixel comprise an intensity value, a hue value, and a chroma value, the intensity value representing the total sensed light energy associated with the pixel, the hue value representing a dominant or average frequency of the light energy associated with the pixel, and the chroma value representing a measure of the light energy on a side of the visible spectrum complementary to the hue, wherein the generating step comprises converting the three primary color values for the given pixel to a set of values comprising the chroma value, the hue value, and the intensity value, and the converting step comprises determining the intensity value (I) in at least approximate accordance with the relation: I=√{square root over (r 2 +g 2 +b 2 )}; and rendering said color image data, wherein the converting step further comprises: determining a quantity (β) in at least approximate accordance with the relation: β = cos - 1 ⁡ ( 2 ⁢ r - g - b 2 ⁢ I 2 - rg - rb - bg ) ; and determining the hue value (H) in at least approximate accordance with the relation: H = { β , g > b 2 ⁢ π - β , otherwise .