An .mp4 file created via youtube-dl.exe cannot be replayed in SMPlayer

[paxx0]

I would like to know the reason why. Log of SMPlayer is included below:

C:/Program Files/SMPlayer/mpv/mpv.exe --no-config --no-quiet --terminal --no-msg-color --input-ipc-server=C:/Users/hynek0/AppData/Local/Temp/smplayer-mpv-1668 --msg-level=ffmpeg/demuxer=error --no-fs --hwdec=no --sub-auto=fuzzy --vo=direct3d, --priority=normal --no-input-default-bindings --input-vo-keyboard=no --no-input-cursor --cursor-autohide=no --no-keepaspect --wid=789604 --monitorpixelaspect=1 --osd-level=1 --osd-scale=1 --osd-bar-align-y=0.6 --sub-ass --embeddedfonts --sub-ass-line-spacing=0 --sub-scale=1 --sub-font=Arial --sub-color=#ffffffff --sub-shadow-color=#ff000000 --sub-border-color=#ff000000 --sub-border-size=0.75 --sub-shadow-offset=2.5 --sub-font-size=50 --sub-bold=no --sub-italic=no --sub-margin-y=8 --sub-margin-x=20 --sub-codepage=ISO-8859-1 --sub-pos=100 --volume=99 --cache=auto --screenshot-template=cap_%F_%p_%02n --screenshot-format=jpg --screenshot-directory=C:\Users\hynek0\Pictures\smplayer_screenshots --audio-pitch-correction=yes --af-add=@aeq:lavfi=[firequalizer=gain='cubic_interpolate(f)':zero_phase=on:wfunc=tukey:delay=0.027:gain_entry='entry(0,0);entry(62.5,0);entry(125,0);entry(250,0);entry(500,0);entry(1000,0);entry(2000,0);entry(4000,0);entry(8000,0);entry(16000,0)'] --volume-max=100 --term-playing-msg=MPV_VERSION=${=mpv-version:}
INFO_VIDEO_WIDTH=${=width}
INFO_VIDEO_HEIGHT=${=height}
INFO_VIDEO_ASPECT=${=video-params/aspect}
INFO_VIDEO_FPS=${=container-fps:${=fps}}
INFO_VIDEO_FORMAT=${=video-format}
INFO_VIDEO_CODEC=${=video-codec}
INFO_AUDIO_FORMAT=${=audio-codec-name}
INFO_AUDIO_CODEC=${=audio-codec}
INFO_AUDIO_RATE=${=audio-params/samplerate}
INFO_AUDIO_NCH=${=audio-params/channel-count}
INFO_LENGTH=${=duration:${=length}}
INFO_DEMUXER=${=current-demuxer:${=demuxer}}
INFO_SEEKABLE=${=seekable}
INFO_TITLES=${=disc-titles}
INFO_CHAPTERS=${=chapters}
INFO_TRACKS_COUNT=${=track-list/count}
METADATA_TITLE=${metadata/by-key/title:}
METADATA_ARTIST=${metadata/by-key/artist:}
METADATA_ALBUM=${metadata/by-key/album:}
METADATA_GENRE=${metadata/by-key/genre:}
METADATA_DATE=${metadata/by-key/date:}
METADATA_TRACK=${metadata/by-key/track:}
METADATA_COPYRIGHT=${metadata/by-key/copyright:}
INFO_MEDIA_TITLE=${=media-title:}
INFO_STREAM_PATH=${stream-path}
 --term-status-msg=STATUS: ${=time-pos} / ${=duration:${=length:0}} P: ${=pause} B: ${=paused-for-cache} I: ${=core-idle} VB: ${=video-bitrate:0} AB: ${=audio-bitrate:0} C:/Users/hynek0/Desktop/FU/bk_acx0_152334_22_64-bk_acx0_152334_22_64.mp4

 (+) Audio --aid=1 (*) (aac 2ch 22050Hz)
[ffmpeg/demuxer] mov,mp4,m4a,3gp,3g2,mj2: Incorrect number of samples in encryption info
[lavf] error reading packet: Invalid data found when processing input.
[ffmpeg/demuxer] mov,mp4,m4a,3gp,3g2,mj2: Incorrect number of samples in encryption info
[lavf] error reading packet: Invalid data found when processing input.
[ffmpeg/demuxer] mov,mp4,m4a,3gp,3g2,mj2: Incorrect number of samples in encryption info
[lavf] error reading packet: Invalid data found when processing input.
MPV_VERSION=mpv 0.32.0
INFO_VIDEO_WIDTH=
INFO_VIDEO_HEIGHT=
INFO_VIDEO_ASPECT=
INFO_VIDEO_FPS=0.000000
INFO_VIDEO_FORMAT=
INFO_VIDEO_CODEC=
INFO_AUDIO_FORMAT=aac
INFO_AUDIO_CODEC=aac (AAC (Advanced Audio Coding))
INFO_AUDIO_RATE=
INFO_AUDIO_NCH=
INFO_LENGTH=17856.609524
INFO_DEMUXER=lavf
INFO_SEEKABLE=yes
INFO_TITLES=
INFO_CHAPTERS=0
INFO_TRACKS_COUNT=1
METADATA_TITLE=
METADATA_ARTIST=
METADATA_ALBUM=
METADATA_GENRE=
METADATA_DATE=
METADATA_TRACK=
METADATA_COPYRIGHT=
INFO_MEDIA_TITLE=bk_acx0_152334_22_64-bk_acx0_152334_22_64.mp4
INFO_STREAM_PATH=C:/Users/hynek0/Desktop/FU/bk_acx0_152334_22_64-bk_acx0_152334_22_64.mp4
INFO_TRACK_0: (error) (error) '' '' (error)
Exiting... (Errors when loading file)

[smplayer-dev]

Can you provide a small sample video where this problem happens?

[paxx0]

Thank you for your interest.
Press "Stáhnout pomalu! here"
here

[smplayer-dev]

Neither mpv nor mplayer can play the video.
The linux command file can't recognize it either:

$ file war5.mp4
war5.mp4: data

Are you sure the video is created correctly?

[paxx0]

I have downloaded it via curl ...

[smplayer-dev]

How? What command did you use?

I think it's best to use youtube-dl.

$ youtube-dl "https://youtu.be/f-mBROeqylY"
[youtube] f-mBROeqylY: Downloading webpage
WARNING: Requested formats are incompatible for merge and will be merged into mkv.
[download] Destination: SMPlayer A Free Media Player with Built-in Codecs-f-mBROeqylY.f136.mp4
[download] 100% of 14.46MiB in 00:05
[download] Destination: SMPlayer A Free Media Player with Built-in Codecs-f-mBROeqylY.f251.webm
[download] 100% of 2.73MiB in 00:01
[ffmpeg] Merging formats into "SMPlayer A Free Media Player with Built-in Codecs-f-mBROeqylY.mkv"
Deleting original file SMPlayer A Free Media Player with Built-in Codecs-f-mBROeqylY.f136.mp4 (pass -k to keep)
Deleting original file SMPlayer A Free Media Player with Built-in Codecs-f-mBROeqylY.f251.webm (pass -k to keep)