Here are some usage scenarios of BatRen.
batren -l -f 15 -p "pic-" -s "-sea" -t 00000 -d outdir *.JPG
The program Will copy all .JPG files to directory outdir, naming them like pic-00015-sea.jpg (extension is forced to lowercase), using 15 as first counter value.
batren -v -m -p "img" -t "00" -d "outdir" *.png
Will move all .png files to directory outdir, naming them like img01.png. If there are more than 100 files, since the padding string has only two characters, it will be adjusted to fit all file names. For example, if there are 101 files, the padding string will become 000.