AM 37 Introductory Image Processing

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• AM 37 Introductory Image Processing
• Lectures 9-10 The camera
• Contents
• The imaging device
• The 3D-to-2D transformation of the pin hole
  model
• Camera calibration
• Radial distortion

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Rays in a simplified digital camera

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• Thin-lens formula a -1 b -1 f -1
• The image at right shows a camera lens with
• f 12 mm (fixed)
• Distance b set so that a bf/(b-f) 3 ft 0.9
  m
• aperture set to 2.8. Thus the aperture angle
  0.36 radians. (Exact definition aperture
  f/ddiaphragm)

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Depth of focus

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Camera geometry Global frame X-Y-Z
Image coordinates (u,v), Camera frame x-y-z
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The camera transformation using the pin hole
model The object coordinate (x,y,z) in the
camera frame related to the image coordinate (u,v)
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Transformation from the global frame to the
camera frame
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The full camera transformation expressed by a 4x3
camera matrix
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Using relations between 3D points and their images
SHB p. 455
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Task 2
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Task 3
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Conversion between internal and external camera
parameters
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Deviations from the pin hole model of a camera
Image distortion
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