The spatstat library uses a different format for images, which have class "im". This utility converts a cimg object to an im object. spatstat im objects are limited to 2D grayscale images, so if the image has depth or spectrum > 1 a list is returned for the separate frames or channels (or both, in which case a list of lists is returned, with frames at the higher level and channels at the lower one).
cimg2im(img, W = NULL)an image of class cimg
a spatial window (see spatstat doc). Default NULL
an object of class im, or a list of objects of class im, or a list of lists of objects of class im
im, as.im