@cindex PBM
For PBM images, specify image type @code{pbm}. Color, gray-scale and
-monochromatic images are supported.
+monochromatic images are supported. For mono PBM images, two additional
+image properties are supported.
+
+@table @code
+@item :foreground @var{foreground}
+The value, @var{foreground}, should be a string specifying the image
+foreground color. This color is used for each pixel in the XBM that is
+1. The default is the frame's foreground color.
+
+@item :background @var{background}
+The value, @var{background}, should be a string specifying the image
+background color. This color is used for each pixel in the XBM that is
+0. The default is the frame's background color.
+@end table
For JPEG images, specify image type @code{jpeg}.