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Histogram
The Histogram collects the total amount of pixels (vertical-axis) for each of the possible intensity values (horizontal-axis) for each of the color channels. The histogram is taken over the currently selected area and works best for a small rectangular selection(See 4.4).
Right-click on the graph for more options. To save the histogram data to a file (tab-separated text) right-click on the graph and select Save Graph Data As....
When the histogram is being displayed, if you right-click on the graph and select Show Control Window the following Analysis Graph Controls are available.
By default the histogram data is displayed in Combined RGB mode. The Analysis Graph Controls can be used to display a luminance graph as well. When displaying a luminance graph the user has the option to display additional data characteristics.
The graph calculates approximate mean from the histogram. So the precision is limited by the size of the histogram bins. That's why it says " ~161 ". Likewise for the other statistical calculations on the graph.
Noise
The Noise graph shows the intensity (vertical-axis) of a single pixel for each frame for all color channels. The old values remain so an intensity-over-time (horizontal-axis) graph appears. This display wraps around and shows approximately 640 time slices. The text at the top display computed temporal SNR in dB. (If there is no fluctuation in the data, the readout shows 0.0.)
Additional Data displayed;
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