[FFmpeg-user] Unknown encoder 'libfdk-aac'

[JD]

Hi,
I do have libfdk-aac
$ ll /usr/lib64/*fdk*
-rw-r--r--. 1 root jd    13942 Sep 24 12:37 /usr/lib64/libfdk-aacdec.c
-rw-r--r--. 1 root jd    16647 Sep 24 12:37 /usr/lib64/libfdk-aacenc.c
lrwxrwxrwx. 1 root root     19 Feb 23 13:56 /usr/lib64/libfdk-aac.so ->
libfdk-aac.so.1.0.0
lrwxrwxrwx. 1 root root     19 Feb 23 13:56 /usr/lib64/libfdk-aac.so.1 ->
libfdk-aac.so.1.0.0
-rwxr-xr-x. 1 root root 765464 Feb 23 13:54 /usr/lib64/libfdk-aac.so.1.0.0

but encoding a video using the command

~/bin/ffmpeg.d/ffmpeg -i video_Z10.mp4 -movflags +faststart -vb 8000k -c:a
libfdk-aac -ab 384k -s 1920x1080 -y video_Z10-libfdk.mp4

ffmpeg version 3.0.2-static http://johnvansickle.com/ffmpeg/  Copyright (c)
2000-2016 the FFmpeg developers
  built with gcc 5.3.1 (Debian 5.3.1-16) 20160424
  configuration: --enable-gpl --enable-version3 --enable-static
--disable-debug --enable-libmp3lame --enable-libx264 --enable-libx265
--enable-libwebp --enable-libspeex --enable-libvorbis --enable-libvpx
--enable-libfreetype --enable-fontconfig --enable-libxvid
--enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora
--enable-libvo-amrwbenc --enable-gray --enable-libopenjpeg --enable-libopus
--enable-libass --enable-gnutls --enable-libvidstab --enable-libsoxr
--enable-frei0r --enable-libfribidi --disable-indev=sndio
--disable-outdev=sndio --enable-librtmp --enable-libmfx --enable-libzimg
--cc=gcc
  libavutil      55. 17.103 / 55. 17.103
  libavcodec     57. 24.102 / 57. 24.102
  libavformat    57. 25.100 / 57. 25.100
  libavdevice    57.  0.101 / 57.  0.101
  libavfilter     6. 31.100 /  6. 31.100
  libswscale      4.  0.100 /  4.  0.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'video_Z10.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    creation_time   : 2016-05-26 13:17:32
    encoder         : Lavf56.1.0
  Duration: 01:18:49.98, start: 0.000000, bitrate: 2238 kb/s
    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv,
bt709), 1280x720 [SAR 1:1 DAR 16:9], 2099 kb/s, 59.94 fps, 59.94 tbr, 90k
tbn, 119.88 tbc (default)
    Metadata:
      creation_time   : 2016-05-26 13:17:32
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz,
stereo, fltp, 125 kb/s (default)
    Metadata:
      creation_time   : 2016-05-26 13:17:32
      handler_name    : SoundHandler
Unknown encoder 'libfdk-aac'

How do I make use of libfdk-aac?