Menu: Image -> Pixel Profile.
Use Pixel Profile to display a graph of pixel values or a pixel profile from a line drawn between two arbitrary points on an image.
The Pixel Profile chart always shows the pixel values as if the image were a 24 bit color image, showing the Red, Green, Blue, Intensity, Hue, Saturation and Value channels.
Generating a graph of a line of pixels may be useful in the analysis of an image. Pixel Profile allows testing and counting elements from images.
To generate a Pixel Profile graph you should draw a segment at least two pixels long with the tool or select a line previously drawn (either from Measurements Pane or with the Selection tool).
Note: When working with grayscale images you may want to unselect all color channels in order to see only the intensity channel.
Pixel Profile Chart
The Graph tab displays a two-dimensional chart that shows distance (in pixels) along the line in the x axis, and pixel values on the y axis. The "Pixel Slice" is shown along the top of the graph.
The Pixel Profile Line may include pixels that are up to 1 pixel apart from the line.
The Pixel Profile Chart can be copied to the clipboard as an image or printed.
Pixel Profile Data
The Data tab shows the Pixel Profile Data in a spreadsheet. You can export the Pixel Profile Data to another application by using the Export button, saving it either as a CSV (which can be opened by Excel, Gnumeric, Libre Office Calc and many other spreadsheet software) or HTML file.
The conversion factor doesn't influence how Pixel Profile works. Pixel Profile always shows the X and Y values in pixels.