Recognition of facial expressions - Knowledge Based Systems ...
Recognition of facial expressions - Knowledge Based Systems ...
Recognition of facial expressions - Knowledge Based Systems ...
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Equation 20<br />
The value <strong>of</strong> the angle is then used for correcting the whole image by rotating it with the<br />
computed angle. Following the rotation procedure, the symmetric <strong>facial</strong> points are<br />
horizontally aligned. The point used as image rotation center is computed to be on the<br />
segment at the half distance between the eyes. The distance between the eyes represents<br />
the new parameter, base , whose value is computed using Equation 21.<br />
The rotation point has the coordinates .<br />
Equation 21<br />
The parameter base is further used to adjust all the distance parameters between any<br />
FCPs for making the recognition process robust to the distance to the camera, and also<br />
person-independent.<br />
Given the value <strong>of</strong> α , all the pixels are rotated on the screen by using Equation 22.<br />
Equation 22<br />
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