Check out example codes for "access to image at from origin". It will help you in understanding the concepts better.

Code Example 1

//use crossorigin="anonymous" sttribute in img tag

<img src="https://upload.wikimedia.org/wikipedia/commons/f/f9/Phoenicopterus_ruber_in_S%C3%A3o_Paulo_Zoo.jpg" id="external-flamingo" crossorigin="anonymous">

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