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Computer Vision – Pattern Recognition<br />

Finally, we can combine the two images to have the center in sharp focus and the<br />

edges softer.<br />

ringed = mh.stretch(im*C + (1-C)*im12)<br />

Now that you know some of the basic techniques of filtering images, you can build<br />

upon this to generate new filters. It is more of an art than a science after this point.<br />

Pattern recognition<br />

When classifying images, we start with a large rectangular array of numbers (pixel<br />

values). Nowadays, millions of pixels are common.<br />

We could try to feed all these numbers as features into the learning algorithm. This is<br />

not a very good idea. This is because the relationship of each pixel (or even each small<br />

group of pixels) to the final result is very indirect. Instead, a traditional approach is to<br />

compute features from the image and use those features for classification.<br />

There are a few methods that do work directly from the pixel values. They have<br />

feature computation submodules inside them. They may even attempt to learn<br />

what good features are automatically. These are the topics of current research.<br />

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