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Welcome back to computer vision.
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Today we're going to talk about, stereo correspondence.
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Up until now we've defined the epipolar geometry that talks about how
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the two views relate, and how if you have a point in the left image,
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then if you know the camera's relation, it's a one dimensional search.
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And in general, the epipolar lines can be,
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well, arbitrary, not arbitrary, but skewed in a variety of ways and located.
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But today, in order to make life easier, we're going to assume a bunch of,
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simplifying assumptions.
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For example, we're going to assume, basically the geometry that we
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drew out last time, of parallel, or coplanar actually, image planes.
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We're going to assume the same focal lengths of the two cameras.
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We're going to assume that they're,
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the cameras are horizontally aligned at the same height.
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So we're, and that the images are pulled out such that the epipolar lines,
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are horizontal, and, that they are, in fact lined up, so a xy location
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in one image is at a different x but the same y location in the other image.
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So look, that's a lot of assuming, and for real stereo, you wouldn't be
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able to do that, you'd have to do a rectification of the image first.
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We'll talk about that, couple lectures from now.
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But for now, we'll make the assumptions which will allow us to
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attack the correspondence problem more easily, and in fact,
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it's the way you're going to be doing correspondence on the problems sets.