youtube-dl ffmpeg post processor not found

ffmpeg.txt

$ ffmpeg
dyld: Library not loaded: /usr/local/opt/x265/lib/libx265.165.dylib
  Referenced from: /usr/local/bin/ffmpeg
  Reason: image not found
Abort trap: 6

youtube-dl-ffmpeg.txt

$ youtube-dl 'https://www.youtube.com/playlist?index=1&playnext=1&list=UUvhTLyVmOpYDPjj5AH1igvg' --verbose
[debug] System config: []
[debug] User config: [u'--prefer-free-formats', u'--mark-watched', u'--prefer-ffmpeg']
[debug] Custom config: []
[debug] Command-line args: [u'https://www.youtube.com/playlist?index=1&playnext=1&list=UUvhTLyVmOpYDPjj5AH1igvg', u'--verbose']
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2019.03.01
[debug] Python version 2.7.15 (CPython) - Darwin-17.7.0-x86_64-i386-64bit
[debug] exe versions: avconv 12.3, avprobe 12.3, ffmpeg present, ffprobe present, phantomjs 2.1.1, rtmpdump 2.4
[debug] Proxy map: {}
[youtube:playlist] UUvhTLyVmOpYDPjj5AH1igvg: Downloading webpage
[download] Downloading playlist: Uploads from ViTrox Corporation Berhad
[youtube:playlist] playlist Uploads from ViTrox Corporation Berhad: Downloading 48 videos
[download] Downloading video 1 of 48
[youtube] 0uJ8zXnaeXM: Downloading webpage
[youtube] 0uJ8zXnaeXM: Downloading video info webpage
[youtube] 0uJ8zXnaeXM: Downloading MPD manifest
[debug] Default format spec: bestvideo+bestaudio/best
[debug] Invoking downloader on u'https://r8---sn-uh-30aes.googlevideo.com/videoplayback/id/d2e27ccd79da7973/itag/137/source/youtube/requiressl/yes/mn/sn-uh-30aes,sn-30a7yn7y/mm/31,29/mv/m/ms/au,rdu/pl/18/initcwndbps/776250/ei/vquGXOCsAomA3LUPjPGDiAo/ratebypass/yes/mime/video%2Fmp4/otfp/1/gir/yes/clen/134616385/lmt/1550559549216214/dur/420.466/fvip/2/mt/1552329559/disable_polymer/true/ip/115.133.43.224/ipbits/0/expire/1552351262/sparams/ip,ipbits,expire,id,itag,source,requiressl,mn,mm,mv,ms,pl,initcwndbps,ei,ratebypass,mime,otfp,gir,clen,lmt,dur/signature/44B6EDC404B4935AF853A82FFA57D8B9FA212797.8402298395A2ADD3C5B130AE903DF044BF0AEDC8/key/dg_yt0/'
[download] IPC CFX 2019 VITROX expands products and facilities-0uJ8zXnaeXM.f137.mp4 has already been downloaded
[download] 100% of 128.38MiB
[debug] Invoking downloader on u'https://r8---sn-uh-30aes.googlevideo.com/videoplayback/id/d2e27ccd79da7973/itag/140/source/youtube/requiressl/yes/mn/sn-uh-30aes,sn-30a7yn7y/mm/31,29/mv/m/ms/au,rdu/pl/18/initcwndbps/776250/ei/vquGXOCsAomA3LUPjPGDiAo/ratebypass/yes/mime/audio%2Fmp4/otfp/1/gir/yes/clen/6806705/lmt/1550559532223029/dur/420.536/fvip/2/mt/1552329559/disable_polymer/true/ip/115.133.43.224/ipbits/0/expire/1552351262/sparams/ip,ipbits,expire,id,itag,source,requiressl,mn,mm,mv,ms,pl,initcwndbps,ei,ratebypass,mime,otfp,gir,clen,lmt,dur/signature/24D78E5EAE4A4A987FFCF3EDFDFDA4444E1A3908.2A4267396BDD08424504F9FEF077488B4D41B822/key/dg_yt0/'
[download] IPC CFX 2019 VITROX expands products and facilities-0uJ8zXnaeXM.f140.m4a has already been downloaded
[download] 100% of 6.49MiB
[ffmpeg] Merging formats into "IPC CFX 2019 VITROX expands products and facilities-0uJ8zXnaeXM.mp4"
[debug] ffmpeg command line: ffmpeg -y -loglevel 'repeat+info' -i 'file:IPC CFX 2019 VITROX expands products and facilities-0uJ8zXnaeXM.f137.mp4' -i 'file:IPC CFX 2019 VITROX expands products and facilities-0uJ8zXnaeXM.f140.m4a' -c copy -map '0:v:0' -map '1:a:0' 'file:IPC CFX 2019 VITROX expands products and facilities-0uJ8zXnaeXM.temp.mp4'
ERROR:   Reason: image not found
Traceback (most recent call last):
  File "/usr/local/bin/youtube-dl/youtube_dl/YoutubeDL.py", line 2052, in post_process
    files_to_delete, info = pp.run(info)
  File "/usr/local/bin/youtube-dl/youtube_dl/postprocessor/ffmpeg.py", line 512, in run
    self.run_ffmpeg_multiple_files(info['__files_to_merge'], temp_filename, args)
  File "/usr/local/bin/youtube-dl/youtube_dl/postprocessor/ffmpeg.py", line 235, in run_ffmpeg_multiple_files
    raise FFmpegPostProcessorError(msg)
FFmpegPostProcessorError:   Reason: image not found