Patent ID: 7127112

Claim:
A method of processing a plurality of source images, comprising the steps of: encoding the plurality of source images to thereby provide a composite image suitable for rendering as a rendered composite image, the encoding including mapping of source image values at pixel locations in the source images to colorant control values { A j } j = 1 M at respective pixel locations in a spectrally-multiplexed image plane, whereby the colorant control values specify an amount of each one of a plurality of colorants to be deposited at corresponding locations in the rendered composite image, and the rendered composite image being suited for image capture by a detector having a plurality of N sensors having respective sensitivities as a function of wavelength λ given by { V 1 ⁡ ( λ ) } i = 1 N , rendering the composite image on a substrate by use of a plurality of M colorants; and recovering a desired one of the encoded source images from the rendered composite image, such that the recovered source image is made distinguishable, by subjecting the rendered composite image to an illuminant provided from an illuminant source and to the plurality of N sensors, so as to detect the resulting recovered source image; wherein the output spectral reflectance produced when the colorant control values are employed for each of the M colorants is given by: r (λ; A 1 , A 2 , . . . A M )=reflectance of region with colorant control values A 1 , A 2 , . . . A M at wavelength λ wherein the relation between the control values used for each of the M colorants at a given pixel location and the response produced at a given pixel location by each of the N sensors is given by: ƒ i ( A 1 , A 2 , . . . A M )=response of i-th capture device to a region with colorant control values A 1 , A 2 , . . . A M =∫ λ V i (λ) r (λ; A 1 , A 2 , . . . A M )dλ i =1,2 . . . N whereby the encoding of each source image is performed according to a determination for optimizing the effects of the following on at least one of the encoding, rendering, and recovery steps: (a) the spectral absorption characteristics of the colorants selected for rendering the composite image: (b) the spectral radiance characteristic of the illuminant that is used to illuminate the composite image for recovering the source image; and (c) the spectral response characteristics of the sensors used to sense the rendered composite image during such illumination, for recovery of the desired source image.