Hi, I research a project that needs to capture the deviation of the camera lens with distortion rate, do you have any idea how can i do that or do you know a journal to suggest to me?
Görüntünün bozulmaması kamera ve görüntü düzenini gelme açısı, yansıma açısı ve yüzeyin normali sapma açısına göre ayarlanmalı ve aynı düzlemde olmalı, görüntü için gerekli koşullar sağlanmalıdır.
The wording of your question is a bit confusing. If my response does not properly answer you question, I apologize.
The distortion of a camera is most easily measured by taking an image of a known object at a known distance. A grid of black lines on a white background is a good choice. The grid should be large enough to fill the field of view when placed at a variety of object distances representative of how the camera will actually be used. The lines should be thick enough to cover most of a pixel width at the largest used object distance. Knowing the true spacing of the grid lines and the true object distance at each tested focal position, the true angular position of each node in the grid is a simple matter of trigonometry. Taking an image at each focal position you are looking for a transform that relates the pixel coordinates of each node in the image to the true angular positions derived from trigonometry.
The distortion is usually radially symmetric. Take the radial position of each node in the image Ri* = sqrt(xi^2 + yi^2) where xi and yi are pixel values. In an undistorted image this is linearly proportional to the true radial position Ri. That is Ri* = c Ri where c is a constant scaling factor that scales pixels to true angles and should be the pixel size over the focal length. You can plot Ri* vs Ri and then fit a function. There are many forms of distortion, and any function that you pick that fits the relation is valid. However, very often the distortion is well described by a simple quadratic: Ri* = c Ri (1 + d Ri). Where d is another constant. The distortion D is typically defined as the difference at any location between what is expected and what is seen (usually expressed as a percent error). In the notation above that’s D = 100 (Ri* - c Ri)/(c Ri). Plugging in the case where the distortion is quadratic D = 100 d/c
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