Matching a rotated bitmap with a collage image

Question

My problem is that I have an image of a detailed street map. This map may have a certain small image of a sign (for example, a traffic light icon), rotated at any angle, possibly of a resized size. I have this small image in a bitmap. Is there any algorithm or method by which I can find this bitmap if its copy exists, is rotated and, possibly, changed, in the image of a large collage?

This seems like a problem with augmented reality and finding marker images, but mine is only 2D without perspective distortion.

Edit: a small bitmap image and its copy in the collage image that I want to fit with is about the same size, possibly 30% of the maximum size difference. The rotation is purely 2D, without shifting or any distortion.

Answer 1

That's a very difficult question.

First: What are the permissions for rotation / resizing? If you have enough pixels to avoid anti-aliasing effects, then you can be fine, but if one or the other image of the sign is very small (i.e., it is small in the collage or small in the picture you choose), rotate it at an arbitrary angle may be bad.

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