when compressing this image
(It corresponds to Fig2.20 from the book Digital Image Processing by Gonzalez and Woods and the original .tif document can be downloaded through this link
Just out of curiosity, does anybody know what the origin for those is? I am puzzled as to whether they originate
at a physical level, like small stains on the lens that took the photograph, (although they suspiciously stop near the watch)
at the transition of the signal into digital form when the image is captured by the pixels of the camera for example
at some step of compressing/ converting the image from one format to the other to obtain the .tif image. Thanks for your help!