Lors de l’installation de ffmpeg-php et que vous tapez phpize et que ça vous donne cette erreur :

$ phpizeconfigure.in:9: warning: underquoted definition of PHP_WITH_PHP_CONFIGrun info ‘(automake)Extending aclocal’or see http://sources.redhat.com/automake/automake.html#Extending-aclocalconfigure.in:32: warning: underquoted definition of PHP_EXT_BUILDDIRconfigure.in:33: warning: underquoted definition of PHP_EXT_DIRconfigure.in:34: warning: underquoted definition of PHP_EXT_SRCDIRconfigure.in:35: warning: underquoted definition of PHP_ALWAYS_SHAREDacinclude.m4:19: warning: underquoted definition of PHP_PROG_RE2Cconfigure.in:65: error: possibly undefined macro: AC_PROG_LIBTOOLIf this token and others are legitimate, please use m4_pattern_allow.See the Autoconf documentation.

Le problème est dû que libtool n’est pas installé

$ yum list|grep -i libtoollibtool-libs.i386 1.5.6-4.EL4.1.c4.4 installedlibtool.i386 1.5.6-4.EL4.1.c4.4 base

$ yum install libtool

Et le tour est joué