Download Installation and User Guide for DVT Vision Sensors

Figure 22: Example of a Pixel Graph for a line Vision Tool of 408 pixels in length.
As the graph illustrates, the pixels near the center of the Vision Tool are dark (low intensities), then, a
light region is found so the graph peaks up to the high intensities and then it goes back down towards
the low intensities as it approaches the end of the Vision Tool. This occurs on each side of the center.
Histograms are also used to display the intensity of the pixels, but in bar chart format. Unlike pixel
graphs, histograms use the intensity levels (ranging from 0 to 100) as the abscissa; for the ordinate, they
use the percent pixels. That is, histograms display the percentage of the pixels found at every intensity
level. Figure 23 shows a histogram for an intensity Vision Tool. The histogram shows two well defined
groups of pixels which may represent background (darker pixels) and the actual part (lighter pixels).
Figure 23: Screen capture of a histogram.
The third image graph is the gradient graph. This type of graph plots changes in intensity values from
pixel to pixel along the path of the Vision Tool. It does not show the actual intensity value of the pixels,
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