Abstract
We describe a segmentation-based object map correction algorithm, which can be integrated in a new imaging
pipeline for laser electrophotographic (EP) printers. This new imaging pipeline incorporates the idea of
object-oriented halftoning, which applies different halftone screens to different regions of the page, to improve the
overall print quality. In particular, smooth areas are halftoned with a low-frequency screen to provide more
stable printing; whereas detail areas are halftoned with a high-frequency screen, since this will better reproduce
the object detail. In this case, the object detail also serves to mask any print defects that arise from the use of
a high frequency screen. These regions are defined by the initial object map, which is translated from the page
description language (PDL). However, the information of object type obtained from the PDL may be incorrect.
Some smooth areas may be labeled as raster causing them to be halftoned with a high frequency screen, rather
than being labeled as vector, which would result in them being rendered with a low frequency screen. To
correct the misclassification, we propose an object map correction algorithm that combines information from the
incorrect object map with information obtained by segmentation of the continuous-tone RGB rasterized page
image. Finally, the rendered image can be halftoned by the object-oriented halftoning approach, based on the
corrected object map. Preliminary experimental results indicate the benefits of our algorithm combined with
the new imaging pipeline, in terms of correction of misclassification errors.
