| 摘要 |
<p>In electronic reproduction technology, a recognition circuit for hues and colors in colored surfaces is provided. Before the actual hue recognition, the hue to be recognized is selected and its prescribed or measure color values of the RGB color space are transformed by a first color transformation into chrominance values of the chrominance/luminance color space, whereby the transformation coefficients are defined such that the transformed color locus of the hue to be recognized lies on a rotated X'Y' color coordinate system in the chrominance plane. During the actual hue recognition, the colored surface is opto-electronically scanned and the measured color values acquired are transformed into chrominance values by a second color transformation with the transformation coefficients defined in the first color transformation. By selection of chrominance values and by quotient formation of the selected chrominance values, a hue signal which is a measure for hue deviation of the scanned hues from the hue to be recognized is generated. After combination of the hue signal with an auxiliary control signal, a hue recognition signal is formed, this being unequal to zero when the scanned hues lie within a sector-shaped hue recognition region. For color recognition, a color saturation signal and a luminance signal are additionally generated. The color saturation signal and luminance signal are adjustably limited in terms of amplitude and are combined with the hue recognition signal to form a color recognition signal.</p> |
