Illustrations convey overall shape as well as surface detail using certain lighting and shading principles. We investigate the use of such an illustration-inspired lighting model to accentuate features automatically by dynamically modulating the light position.
We apply this shading technique to accentuate detail in volumetric
data. As the technique is primarily a gradient-based technique,
we discuss and compare gradient computation techniques and their
effectiveness. The technique highlights details at various levels in
the volume making use of the multiple levels of blurred gradients
computed. The results demonstrate that surface detail is accentuated
regardless of the surface orientation and the size of features.
We have applied our techniques to scientific and medical data to
accentuate surfaces features in the application domains.