[FFmpeg-user] Option rc_eq not found | conversion failed

[Anthony Griffiths]

I'm using ffmpeg to stream a live broadcast to another machine running
ffserver but the process won't run and I keep betting the error:
"Option rc_eq not found
Conversion failed!"

This is the ffmpeg command:
# .../ffmpeg-git-20171101-64bit-static/ffmpeg -y -f mpegts -i
/dev/dvb/adapter0/dvr0 -codec:v libx264 -preset slow -s 320x180 -b:v 500k
-maxrate 500k -bufsize 1000k -r 10 -vf scale=-1:240 -threads 0 -codec:a
libmp3lame -b:a 64k http://ffserver-machine:8090/feed1.ffm

and this is the log output:

---------------------------------
ffmpeg version N-88441-g17806f6083-static https://johnvansickle.com/ffmpeg/
Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 6.4.0 (Debian 6.4.0-9) 20171026
  configuration: --enable-gpl --enable-version3 --enable-static
--disable-debug --disable-ffplay --disable-indev=sndio
--disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r
--enable-gnutls --enable-gray --enable-libfribidi --enable-libass
--enable-libvmaf --enable-libfreetype --enable-libmp3lame
--enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg
--enable-librubberband --enable-librtmp --enable-libsoxr --enable-libspeex
--enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab
--enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264
--enable-libx265 --enable-libxvid --enable-libzimg
  libavutil      56.  0.100 / 56.  0.100
  libavcodec     58.  1.100 / 58.  1.100
  libavformat    58.  0.102 / 58.  0.102
  libavdevice    58.  0.100 / 58.  0.100
  libavfilter     7.  0.101 /  7.  0.101
  libswscale      5.  0.101 /  5.  0.101
  libswresample   3.  0.101 /  3.  0.101
  libpostproc    55.  0.100 / 55.  0.100
[mpeg2video @ 0x5725ce0] Invalid frame dimensions 0x0.
    Last message repeated 19 times
Input #0, mpegts, from '/dev/dvb/adapter0/dvr0':
  Duration: N/A, start: 56606.378156, bitrate: N/A
    Stream #0:0[0x5de]: Audio: mp2, 48000 Hz, stereo, s16p, 192 kb/s
    Stream #0:1[0x5dd]: Video: mpeg2video (Main), yuv420p(tv, top first),
720x576 [SAR 16:15 DAR 4:3], 25 fps, 25 tbr, 90k tbn, 50 tbc
[NULL @ 0x573f000] Key 'rc_eq' not found.
Codec AVOption preset (Configuration preset) specified for output file #0 (
http://198.91.92.112:8090/feed1.ffm) has not been used for any stream. The
most likely reason is either wrong type (e.g. a video option with no video
streams) or that it is a private option of some encoder which was not
actually used for any stream.
Stream mapping:
  Stream #0:0 -> #0:0 (mp2 (native) -> vorbis (libvorbis))
  Stream #0:1 -> #0:1 (mpeg2video (native) -> vp8 (libvpx))
Press [q] to stop, [?] for help
[libvpx @ 0x5724460] v1.6.1-1350-g0c84b9b70
Option rc_eq not found.
[libvorbis @ 0x5791f40] 27 frames left in the queue on closing
Conversion failed!
------------------------------

this is the /etc/ffserver.conf file running on the receiving machine:

Port 8090                      # Port to bind the server to
BindAddress 0.0.0.0
MaxHTTPConnections 2000
MaxClients 1000
MaxBandwidth 10000             # Maximum bandwidth per client
                               # set this high enough to exceed stream
bitrate
CustomLog -
NoDaemon                       # Remove this if you want FFserver to
daemonize after start

<Feed feed1.ffm>               # This is the input feed where FFmpeg will
send
   File ./feed1.ffm            # video stream.
   FileMaxSize 1G              # Maximum file size for buffering video
   ACL allow 127.0.0.1         # Allowed IPs
</Feed>

<Stream test.webm>                      # Output stream URL definition
   Feed feed1.ffm              # Feed from which to receive video
   Format webm

   # Audio settings
   AudioCodec vorbis
   AudioBitRate 64             # Audio bitrate

   # Video settings
   VideoCodec libvpx
   VideoSize 720x576           # Video resolution
   VideoFrameRate 25           # Video FPS
   AVOptionVideo flags +global_header  # Parameters passed to encoder
                                       # (same as ffmpeg command-line
parameters)
   AVOptionVideo cpu-used 0
   AVOptionVideo qmin 10
   AVOptionVideo qmax 42
   AVOptionVideo quality good
   AVOptionAudio flags +global_header
   PreRoll 15
   StartSendOnKey
   VideoBitRate 400            # Video bitrate
</Stream>

<Stream status.html>                    # Server status URL
   Format status
   # Only allow local people to get the status
   ACL allow localhost
   ACL allow 192.168.0.0 192.168.255.255
</Stream>

<Redirect index.html>    # Just an URL redirect for index
   # Redirect index.html to the appropriate site
   URL http://www.ffmpeg.org/
</Redirect>

I've been trawling google but can't find any solution as to what "rc_eq not
found" actually is. Thanks for any help.