In an attempt to stay on-topic, I offer (untested):

1 .    !~/\.(?:jpg|png|gif)$/ 

2.   perl -e '$f=shift(); -e $f and do{ my ($r,$d)=$f=~/(.+?)(\d*)$/; 
+$d++; $NEWFILENAME=qq|$r$d\n|}'
[download]

More <to-the-point> answers may follow, if asked politely.