1. A method of guiding a vehicle, the method comprising: collecting color image data to distinguish crop image data from background image data; wherein the collecting further comprises classifying image data as crop image data if a green-red difference associated with a pixel is greater than a first threshold value and if a green-blue difference associated with the pixel is greater than a second threshold value, and wherein the green-red difference (D g−r ) is defined as D g−r =G−R and the green-blue difference (D g−b ) is defined as D g−b =G−B, where R,G,B are the pixel's red, green and blue component, respectively, in RGB color space; defining a series of scan line segments generally perpendicular to a transverse axis of the vehicle or of an imaging system; determining, by a data processor, a scan-line-image-parameter level for each of the scan line segments, the scan-line-image-parameter level comprising a color-related parameter level; and identifying a preferential heading of the vehicle that is generally aligned with respect to a crop feature, associated with crop image data, based on the determined scan-line-image-parameter level meeting or exceeding a maximum value or minimum threshold value.