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In this paper, we used hybrid optoelectronic joint transform correlator (HOJTC) for recognition of moving target.
HOJTC is one of the most successful optical pattern recognizer which is composed of laser, spatial filter, Fourier
transform lenses, EALCD (electrically addressed liquid crystal displays) and CCD (Charge Coupled Device). It has
many applications in the fields of industry and military affairs.
The speed of armored vehicle is generally less than 80 km/h. CCD used as receiver can capture 25 frames per second.
The difference caused by shape, scale and rotation always exists between template and target. Therefore, the optical
correlator can only detect captured moving target about 3 to 5 serial frames. For some targets in cluttered scene, it even
can not recognize the target, which means the tracked target is missing. It shows the influence of clutter and distortion
brings great difficulty to correlation recognition. In order to realize scale invariable and rotation invariable, the method of
adaptive threshold is applied. After processing the images of moving targets, we can reduce the influence of cluttered
background. The effect brought by the changes of shape, scale and rotation is also reduced. Consequently, the ability of
automatic recognition, location and tracking of moving target by HOJTC can be enhanced greatly.
The experiments are performed to recognize moving tanks with high speed about 70 km/h. The experiments show that
more than 80 serial frames can be recognized after target images are processed. The joint transform correlator can
recognize even more than 150 frames when the target is in relative clean scene. It has great meaning for target detection
and tracking. The conclusion can be drawn that the proposed method of adaptive threshold for moving target is feasible,
and it could effectively enhance the ability of automatic recognition and tracking of a moving target.
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