How to get patches?

[KarlThelor]

Since the keypoints are detected from distorted images,how to get patches from undistort images ?

[lzx551402]

it is indeed a bit troublesome, you may first refer to this example for point undistortion. I will write another example to address your concern.

[KarlThelor]

Much obliged,that would be great helpful

[Archaon6734]

Your work are great，but I have a similar problem,we can get the keypoint location in undistort images just as example "(x, y) = (TRANSFORMATION[0, 2] * W/2 + W/2, TRANSFORMATION[1, 2] * H/2 + H/2)"
what's the meaning of TRANSFORMATION[0, 0],and TRANSFORMATION[0, 1]?
If they are the reslut of transformation in GeoDesc 3.2,and if I want get the correnspond patch in differnt scale image,it seems like that I need solve a trigonometric equation to get scale (σ) and orientation (θ) parameters of SIFT.

[lzx551402]

@KarlThelor @Archaon6734 Hi two, thank you for your concerning. I write an example to address your concerns, you may now call python visualize.py patch to extract the matching patches. You will be able to see something like this.

I think this fragment of code would better explain your questions.

[Archaon6734]

It really solved my troubles，I really appreciate your help，thanks!