Definitions for "image histogram"
Keywords:  pixel, abscissa, graph, gray, analytic
a graphical plot displaying input pixel values on the x -axis (referred to as a bin ) versus the number (or relative number) of pixels for any given bin value on the y axis
a graphic representation of how many pixels have a specific gray value
a graph showing each gray level and the number of pixels for each level
a chart that shows the distribution of intensities in an image