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Submitted version of the thesis - Airlab, the Artificial Intelligence ...

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64 Chapter 5. Vision<br />

in a form that can be converted into <strong>the</strong> rules. The result <strong>of</strong> <strong>the</strong> color selection<br />

script, with <strong>the</strong> original picture is shown in Figure 5.7.<br />

(a) Mask to be Applied (b) Orginal Picture<br />

Figure 5.7: The mask applied to <strong>the</strong> orginal picture.<br />

The boundaries found for <strong>the</strong> object are converted into rules, that will<br />

add or subtract <strong>the</strong> color from <strong>the</strong> RGB Cube. The rules are checked by<br />

color selection program, provided with <strong>the</strong> ST s<strong>of</strong>tware coming with <strong>the</strong><br />

camera. The script can be found in Appendix B.1 in Color Histogram Calculator.<br />

Using both <strong>the</strong>color selecting program and an <strong>of</strong>fline Matlab script,<br />

we have been able to define <strong>the</strong> color in a more precise way, and improved<br />

<strong>the</strong> results for object detection. But <strong>the</strong> results diverged as <strong>the</strong> lighting<br />

conditions change in <strong>the</strong> environment. For example <strong>the</strong> laboratory where<br />

we have performed tests is exposed to direct sunlight in <strong>the</strong> morning, while<br />

in <strong>the</strong> afternoon it is not. We introduced different configurations for <strong>the</strong><br />

same color, to avoid <strong>the</strong> need for sampling <strong>of</strong> <strong>the</strong> previously defined color.<br />

By controlling <strong>the</strong> color before each run manually and recalculating when<br />

necessary resulted a stable solution to <strong>the</strong> problem.<br />

5.3 Tracking<br />

The final working configuration <strong>of</strong> <strong>the</strong> object detection is made by solving<br />

<strong>the</strong> problems described previously. We can explain <strong>the</strong>se in three titles.<br />

First one is finding <strong>the</strong> correct color information. We start by disabling <strong>the</strong><br />

automatic whitebalanceandautomatic exposurecompensation. Thisallows<br />

us to have <strong>the</strong> color as it is seen directly from <strong>the</strong> camera, by not adjusting

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