We chose the mean-shift algorithm, proposed in [16], over
other segmentation methods, such as level set and graph cutbased
algorithms, for several reasons. First, the mean-shift algorithm
takes into consideration the spatial continuity inside
the image by expanding the original 3-D color range space to
5-D space, including two spatial components, since direct classification
on the pixels proved to be inefficient [16]. Second,
a number of acceleration algorithms are available [17], [23].
Third, for both mean-shift filtering and region merge methods,
the quality of the segmentation is easily controlled by the spatial
and color range resolution parameters [16], [17]. Hence, the
segmentation algorithm can be adjusted to accommodate different
degrees of skin color smoothness by changing the resolution
parameters. Finally, the mean-shift filtering algorithm is suitable
for parallel implementation since the basic processing unit
is the pixel. In this case, the high computational efficiency of
GPUs can be exploited.