I sort images from different sources according to timestamp. For having this available in other applications I'm doing a rename with pic-###. Some of the original pictures have the same name with different suffix (like xx.raw, xx.tif, xx.jpg). In this case I would like rename to keep the identical basename.

Original Name    Current rename     Wanted rename
a-1.jpg   -->    pic-001.jpg        pic-001.jpg
b-1.jpg   -->    pic-002.jpg        pic-002.jpg
b-1.raw   -->    pic-003.raw        pic-002.raw
a-2.jpg   -->    pic-004.jpg        pic-003.jpg
b-2.raw   -->    pic-005.raw        pic-004.raw
b-2.jpg   -->    pic-006.jpg        pic-004.jpg

Greetings, Jens