I'm working on getting libav 9 in portage and it supports a number of new libraries, could you please let me know if I should mask the useflag or wait till you tested it and hopefully works?
Putting fdk in global use mask, once we are set let's remove it. (adding sparc that I forgot)
./libFDK/include/FDK_archdef.h:207:4: error: #error >>>> Please set architecture characterization defines for your platform (FDK_HIGH_PERFORMANCE)! <<<< USE=fdk masked for HPPA.
Use.masked on alpha/ia64/sparc