<HTML><BODY><div> <blockquote style="border-left:1px solid #0857A6; margin:10px; padding:0 0 0 10px;"><div id=""><div class="js-helper js-readmsg-msg"><div><div id="style_16631502901324695802_BODY"><div class="cl_156607"><div>I recommend not to use sws_sclale at all. It is a real bottleneck of all encoding process.</div></div></div></div></div></div></blockquote><div> </div><div> </div><div>If you use the multithreaded version of AVFilter or initialize the context manually to use multithreading, then everything works fast enough.</div><div> </div></div></BODY></HTML>