It is a project related to defect classifying in textile industry.
The input is a set of images with the whole variety of defects encountered
in the fabric. The system has to learn the defects (that means to
be capable of correct recognition after the training step is finished).
The project was made within ASIC
Art for an Israeli client: Elbit
Vision Systems. The percent of correct recognition on the test
set of images (other than the one "learned") was 89% (for
5 kinds of different defects). The solution was a result of my research
because classical solutions didn't give good results (about 50%
of good recognition).
The solution comprises a preprocessing stage and a neural network
based-process. The neural network used was a Multilayer Perceptron
trained with Backpropagation algorithm. In the preprocessing stage
the main features that characterize the defects are extracted from
the original images. It is almost a rule the using of Discrete Cosine
Transform in order to extract the features of an image, this preprocessing
task being a under-optimal transform after Karhunen-Loeve. This
transform didn't give good results, so I had used combined methods
histogram manipulation, Gabor filtering, statistic moments. The
later method allowed us to increase the percent of good recognition.
The pre-processing is an issue under development/research.
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