thankyou for your answer tim. very helpful when i try to build gst-libav, it says libavfilter not found meson.build:18:0: ERROR: Dependency "libavfilter" not found, tried pkgconfig libavfilter should install as a part of libav which is inside gst-libs/ext/libav/. no? -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/