gistfile1.txt

        "ffmpeg -y -f image2pipe -vcodec ppm -framerate 15 -i pipe:0 "
            "-v quiet -threads 1 "
            "-c:v libx264 -maxrate 16000k -preset veryfast -tune zerolatency -pix_fmt yuv444p "
            "-x264opts crf=20:vbv-maxrate=3000:vbv-bufsize=100:intra-refresh=1:slice-max-size=65536:keyint=100:ref=1 "
            "-an -pass 1 -coder 0 -bf 0 -wpredp 0 -profile:v high444 " 
            "-qp 26 -r 15 "
            "-f h264 /dev/stdout"
        },

    2.6 ghz core

   15 fps
   720p   33% 1 core usage
   1080p  44% 1 core usage

   30 fps
   720p  55-65% 1 core
   1080p 80-85% 1core