ldd `which ffmpeg`
	linux-vdso.so.1 (0x00007ffd979e2000)
	libavdevice.so.57 => not found
	libavfilter.so.6 => not found
	libavformat.so.57 => not found
	libavcodec.so.57 => not found
	libpostproc.so.54 => not found
	libswresample.so.2 => not found
	libswscale.so.4 => not found
	libavutil.so.55 => not found
	libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fa7ad62a000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fa7ad40d000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fa7ad062000)
	/lib64/ld-linux-x86-64.so.2 (0x00007fa7ad92b000)