webrtc 4577 version Build error，unresoved symbol avpriv_emms_asm, build with vs2017，x64

[song tu]

hello everybody，recently，I build webrtc 4577 version on windows 10 system，after I down load the  webrtc,  switch to 4577，then build，the command is as follows:

gn gen out/Release_h264 --args="is_clang=false treat_warnings_as_errors=false rtc_include_tests=false is_component_build=false is_debug=false rtc_use_h264=true proprietary_codecs=true ffmpeg_branding=\"Chrome\"" --ide=vs2017

ninja -C out/Release_h264

But，at the last moment， it failed， the picture is as follows.

can anyone help me，thanks a lot

ffmpeg_internal.lib   avpriv_emms_asm

[song tu]

I resolved this problem, first,we need compile ffmpeg on windows, then  add ffmpeg include and lib files to webrtc project