[FFmpeg-devel] Unknown encoder 'libvo_aacenc'

[RITESH MEHANDIRATTA]

i am new to ffmpeg just trying to build an sdp file for streaming .i am
facing error when i run command

ffmpeg -re -i "sample.mp4" -f rtp rtp://127.0.0.1:10000 -flags
+global_header -c:a libvo_aacenc -vn -map 0:1 -f rtp rtp://127.0.0.1:10000 >
10000.sdp

and the error i am facing is Unknown encoder 'libvo_aacenc'

can any one please help how to resolve this error!!