| 摘要 |
<p>The invention relates to spectral imaging, in particular - to imaging of spectral reflectance distribution at a number of fixed wavelengths bands by means of a single RGB image data set. In the proposed method for obtaining a number of spectral reflectance images, the object and attached to it white reflector is illuminated simultaneously at a number of, for instance two or three, spectral bands, ensuring linearity of the photo-response, and the R;-, Gj- and Bj-signal values are identified for every image pixel "i", including those registered at the white reflector zone. If the spectral sensitivity curves of the image sensor R-, G- and B-channels are known, the spectral sensitivities at the illumination wavelengths are fixed. Their ratios are further used to determine the spectral imaging at every pixel or pixel group of the image for every wavelength of the poly-chromatic illumination, using the proposed analytic expressions for calculations. A device for imaging of spectral reflectance at a number of wavelength bands to implement this method comprises a poly-chromatic light source (1), objective-equipped digital RGB sensor (4), white reflector (3) that covers relatively small part of the surface to be imaged (2), RGB data set storage device (5), convertor (6) that converts the RGB data into a set of spectral reflectance values, imager (7) that produces the reflectance images related to each particular spectral band, and the output device (8), e.g. PC-monitor.</p> |
