Comment 9 for bug 905669

It would be fine as a user to be able to choose the accuracy of the rescan algorithm. This way we could control the scanning speed depending on our needs.

I don't have a thorough idea of how the algorithm work, but I suppose some comparisons are done on the file name, size and signature. So the Library pane in the Preference dialog could provide options to tweak which level of information is used for the comparisons during rescan.