[Freeswitch-users] Install Error (libvpx2)

Hi, I have an error below while instaling Freeswitch. making all mod_av make[4]: Entering directory `/usr/local/src/freeswitch/src/mod/applications/mod_av' Makefile:833: *** You must install libvpx2-dev to build mod_av. Stop. make[4]: Leaving directory `/usr/local/src/freeswitch/src/mod/applications/mod_av' make[3]: *** [mod_av-all] Error 1 make[3]: Leaving directory `/usr/local/src/freeswitch/src/mod' make[2]: *** [all-recursive] Error 1 make[2]: Leaving directory `/usr/local/src/freeswitch/src' make[1]: *** [all-recursive] Error 1 make[1]: Leaving directory `/usr/local/src/freeswitch' make: *** [all] Error 2 How can i solve this problem. Thank you.