| Summary: | 碩士 === 國立交通大學 === 資訊科學學系 === 86 === A preprocessing, differential image generation, is proposed in
this thesis to improve the performance of face recognition
systems for recognizing face images degraded by slow-changing
global variation in gray values, such as lighting conditions.
The motivation of using the differential image for face
recognition is resulted from the observation that main features
of a face usually cause more significant changes in the gray
values for image pixels in a small neighborhood than that due to
slow-changing global variation in gray values; therefore, using
the differential image may alleviate the above image problem.
Using the differential image may also speed up the recognition
progress and save the data storage, since the dynamic range of
the gray values of the differential image is much smaller than
the one of the original image. In this thesis, the proposed
method are applied as preprocessing for two face recognition
systems, Eigenface and Fisherface methods. Experimental results
show that the proposed method has good recognition rates when
recognizing degraded images as well as normal ones.
|
|---|
