We designed a test card for the vision threshold and used it to
examine vision thresholds of panelists. Results show that the
vision thresholds of panelists range from 6 to 12, rising with
an increase in the background grey level. An efficient segmentation
algorithm for beef marblingwas presented based on the
vision threshold. By sensory evaluation, comparisons of the PA
to other eight existing algorithmswere conducted. The results
show that PA performsmuch better than RG after introducing
the grader’s vision thresholds and our proposed algorithm can
produce most satisfactory results for the segmentation of beef
marbling among nine algorithms.