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Ever since its origin in the late 19th century, a color reproduction technology has relied on a trichromatic color
reproduction approach. This has been a very successful method and also fundamental for the development of color
reproduction devices. Trichromatic color reproduction is sufficient to approximate the range of colors perceived by the
human visual system. However, tricromatic systems only have the ability to match colors when the viewing illumination
for the reproduction matches that of the original. Furthermore, the advancement of digital printing technology has
introduced printing systems with additional color channels. These additional color channels are used to extend the tonal
range capabilities in light and dark regions and to increase color gamut. By an alternative approach the addition color
channels can also be used to reproduce the spectral information of the original color. A reproduced spectral match will
always correspond to original independent of lighting situation. On the other hand, spectral color reproductions also
introduce a more complex color processing by spectral color transfer functions and spectral gamut mapping algorithms.
In that perspective, spectral vector error diffusion (sVED) look like a tempting approach with a simple workflow where
the inverse color transfer function and halftoning is performed simultaneously in one single operation. Essential for the
sVED method are the available color primaries, created by mixing process colors. Increased numbers of as well as
optimal spectral characteristics of color primaries are expected to significantly improve the color accuracy of the spectral
reproduction. In this study, sVED in combination with multilevel halftoning has been applied on a ten channel inkjet
system. The print resolution has been reduced and the underlying physical high resolution of the printer has been used to
mix additional primaries. With ten ink channels and halfton cells built-up by 2x2 micro dots where each micro dot can be
a combination of all ten inks the number of possible ink combinations gets huge. Therefore, the initial study has been
focused on including lighter colors to the intrinsic primary set. Results from this study shows that by this approach the
color reproduction accuracy increases significantly. The RMS spectral difference to target color for multilevel halftoning
is less than 1/6 of the difference achieved by binary halftoning.
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