yes you can do so by using Recording Rules:
1. Navigate to System Settings > Recorder > Recording Rules.
2. Click Add. The Recording Rule Properties dialog opens.
3. From the Template list box, choose "Suppress Recording by File Extension"
4. Edit the default Rule Name and Description as required.
5. Check the Active check box to activate the rule (done per default).
6. Edit the Condition value to the file type you want to suppress.
7. Click OK. The new rule appears on the Recording Rules page