AN ALGORITHM FOR APPROXIMATE CRINKLE ARTIFACT COMPENSATION IN PRESSURE-SENSITIVE FILM RECORDINGS

An objective, empirically based image-processing technique was devised to compensate for the presence of crinkle artifact in Pressensor pres sure-sensitive film recordings. A spherical indentor was used to produ ce film stains which deliberately included radially directed artifact streaks, superimposed upon otherwise smooth, nearly axisymmetric stain recordings. An interactive, threshold-based search algorithm was deve loped to delineate explicitly the perimeters of specific artifacts pre sent within manually (cursor) circumscribed regions where crinkle feat ures were visually apparent. Three mathematical artifact transformatio n operators were parametrically evaluated in terms of their ability to approximate objectively the corresponding artifact-free axisymmetric pressure fields. All three operators were found to reduce substantiall y the quantitative deviation from the idealized distributions. When ap propriately tuned transformation operators were applied to typical in vitro intraarticular contact stains, the visual prominence of crinkle artifact features was markedly reduced.