Patent ID: 6023525
Filing Date: 2000-02-08
Classification: G06K,H04N

Abstract:
A method for operating a processor-controlled machine to determine, for a given input color, an optimal direction in color space that includes the given input color and that satisfies a set of constraints; the machine including an output device, a processor, and a memory device for storing data; the data stored in the memory device including instruction data the processor executes to operate the machine; the processor being connected to the memory device for accessing and executing the instruction data stored therein; the method comprising:obtaining an input color defined in coordinates of a multi-dimensional color space;specifying an objective function that balances measurements of a human perceptual response and a digital image capture device response to a color change; the color change being defined by a color space direction away from the input color; the objective function simultaneously minimizing the human perceptual response measurement and maximizing the digital image capture device response measurement to the color change;determining an output color defined as an optimal color space direction in the multi-dimensional color space away from the input color using the objective function;encoding data as a pattern comprising one or more picture elements in an output color and one or more picture elements in the input color; andoutputting, on the output device, the encoded data such that the pattern is minimally visually perceptible to humans while, at the same time is maximally detectable by the digital image capture device.