Without the data you want to plot (or an approximation of the data) it becomes a little difficult to offer a full solution.
That said, the following (really offered as an extended comment), may provide you with some strategies to approach what you want to do.
It seems like you want to look at these sorts of: images:
and use a BarLegend
.
You can find many examples in the documentation, e.g., see ComplexPlot
ComplexPlot[(z^2 + 1)/(z^2 - 1), {z, -2 - 2 I, 2 + 2 I}, PlotLegends -> Automatic]
Or ReliefPlot
ReliefPlot[ Table[i + Sin[i^2 + j^2], {i, -4, 4, .03}, {j, -4, 4, .03}], ColorFunction -> "SunsetColors", PlotLegends -> Automatic]
Essentially, if you select an appropriate type of Plot
(ComplexPlot
, ReliefPlot
), to present the data, you'll have a ready option of using BarLegend
.
You can additionally create a BarLegend
and use Show
to display it with an image.
Again, without a bit more information responders will likely need to guess what you want to do.
Maybe you just want to analyze the graphic image itself rather than generate it from the data of an Atomic force microscope (AFM) image.
If so, take a look in the documentation at: Image Processing & Analysis.
ImageMeasurements
might then prove useful.
ImageMeasurements[image, "MeanIntensity"]
{0.194848, 1.}
ImageMeasurements[image, "Entropy"] // N
7.00746
Information[image]
More information about what you need to do will help attract more specific answers.