changing filenames

Posted by Devrim Pesen Okvur-2 on Apr 02, 2011; 3:16pm
URL: http://imagej.273.s1.nabble.com/changing-filenames-tp3685166.html

I would like to change tiff file names as follows:
1- place two zeros in the beginning so that the order is 001 002 ... 100 instead of 1 2 ...100
2- shorten the file name from 1_a_xxx_yyy to 1_a

Combining the two above,  filename of 1_a_xxx_yyy will be changed to 001_a

Any help is appreciated.