Video+audio merge failed on a system with older FFmpeg version (regression)

[nachanon]

This is a recent regression on post-processing, very similar to bug #19067, likely originated from the same root cause.

After upgraded YouTube-DL to current version, I was trying to to download a video from YouTube in 480p H.264 video resolution, combined with 128kbps AAC audio. Note that I have been successfully using the remuxing feature of YouTube-DL on this system before...

Video URL: https://www.youtube.com/watch?v=ueoRSzCn4kA

With the format specified as 135+140, both video and audio downloads completed successfully, but the process failed with a cryptic ERROR: "debug" message at the part where a remuxer would have to run to combine video and audio into a single file (in this case, FFmpeg is the remuxer)...

C>youtube-dl --no-mtime --no-part --format 135+140 --verbose -o ueoRSzCn4kA.480p+m4a128k.mp4 https://www.youtube.com/watch?v=ueoRSzCn4kA
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: ['--no-mtime', '--no-part', '--format', '135+140', '--verbose', '-o', 'ueoRSzCn4kA.480p+m4a128k.mp4', 'https://www.youtube.com/watch?v=ueoRSzCn4kA']
[debug] Encodings: locale cp874, fs mbcs, out cp874, pref cp874
[debug] youtube-dl version 2019.03.09
[debug] Python version 3.4.4 (CPython) - Windows-XP-5.1.2600-SP3
[debug] exe versions: ffmpeg N-49610-gc2dd5a1, ffprobe N-49610-gc2dd5a1
[debug] Proxy map: {}
[youtube] ueoRSzCn4kA: Downloading webpage
[youtube] ueoRSzCn4kA: Downloading video info webpage
[debug] Invoking downloader on 'https://r6---sn-j5u-c33e7.googlevideo.com/videoplayback?mm=31%2C29&mn=sn-j5u-c33e7%2Csn-npoe7n7z&id=o-AJshA2WSiwvN3c9mNYrwKtfz_UkOeXPdLIKb5rdSXbiz&sparams=aitags%2Cclen%2Cdur%2Cei%2Cgir%2Cid%2Cinitcwndbps%2Cip%2Cipbits%2Citag%2Ckeepalive%2Clmt%2Cmime%2Cmm%2Cmn%2Cms%2Cmv%2Cpl%2Crequiressl%2Csource%2Cexpire&ip=159.192.218.249&key=yt6&mt=1552548229&txp=5533432&mv=m&gir=yes&ms=au%2Crdu&clen=123497437&ipbits=0&initcwndbps=1016250&signature=16B2AEC6318BE3AA1E0E141D389E18CC7961F38A.7C49C5D9A62B83A7AB5BD42B9F4043B0327F4878&aitags=133%2C134%2C135%2C136%2C137%2C160%2C242%2C243%2C244%2C247%2C248%2C278&c=WEB&expire=1552569962&mime=video%2Fmp4&dur=1458.080&itag=135&pl=24&source=youtube&keepalive=yes&requiressl=yes&lmt=1540146743788782&ei=CQKKXIX_PPzOz7sPzeStgAI&fvip=6&ratebypass=yes'
[download] Destination: ueoRSzCn4kA.480p+m4a128k.f135.mp4
...
[download] 100% of 117.78MiB in 00:15                          
[debug] Invoking downloader on 'https://r6---sn-j5u-c33e7.googlevideo.com/videoplayback?mm=31%2C29&mn=sn-j5u-c33e7%2Csn-npoe7n7z&id=o-AJshA2WSiwvN3c9mNYrwKtfz_UkOeXPdLIKb5rdSXbiz&sparams=clen%2Cdur%2Cei%2Cgir%2Cid%2Cinitcwndbps%2Cip%2Cipbits%2Citag%2Ckeepalive%2Clmt%2Cmime%2Cmm%2Cmn%2Cms%2Cmv%2Cpl%2Crequiressl%2Csource%2Cexpire&ip=159.192.218.249&key=yt6&mt=1552548229&txp=5533432&mv=m&gir=yes&ms=au%2Crdu&clen=23599223&ipbits=0&initcwndbps=1016250&signature=A87DBAA154F683AFFB3F1C7EFC64CBD0DBF2E214.6D5FFF49467B4B6F03E38584CF41535AD88900A8&c=WEB&expire=1552569962&mime=audio%2Fmp4&dur=1458.143&itag=140&pl=24&source=youtube&keepalive=yes&requiressl=yes&lmt=1540145719628694&ei=CQKKXIX_PPzOz7sPzeStgAI&fvip=6&ratebypass=yes'
[download] Destination: ueoRSzCn4kA.480p+m4a128k.mp4.f140
...
[download] 100% of 22.51MiB in 00:03                          
[ffmpeg] Merging formats into "ueoRSzCn4kA.480p+m4a128k.mp4"
[debug] ffmpeg command line: ffmpeg -y -loglevel "repeat+info" -i "file:ueoRSzCn4kA.480p+m4a128k.f135.mp4" -i "file:ueoRSzCn4kA.480p+m4a128k.mp4.f140" -c copy -map "0:v:0" -map "1:a:0" "file:ueoRSzCn4kA.480p+m4a128k.temp.mp4"
ERROR: "debug"
Traceback (most recent call last):
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\rg3\tmpy110f8qy\build\youtube_dl\YoutubeDL.py", line 2052, in post_process
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\rg3\tmpy110f8qy\build\youtube_dl\postprocessor\ffmpeg.py", line 512, in run
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\rg3\tmpy110f8qy\build\youtube_dl\postprocessor\ffmpeg.py", line 235, in run_ffmpeg_multiple_files
youtube_dl.postprocessor.ffmpeg.FFmpegPostProcessorError: "debug"

C>echo %ERRORLEVEL%
1

Directly running the FFmpeg command shown in Youtube-DL log resulted in an error message, with exit code 1:

C>ffmpeg -y -loglevel "repeat+info" -i "file:ueoRSzCn4kA.480p+m4a128k.f135.mp4" -i "file:ueoRSzCn4kA.480p+m4a128k.mp4.f140" -c copy -map "0:v:0" -map "1:a:0" "file:ueoRSzCn4kA.480p+m4a128k.temp.mp4"
Invalid loglevel "repeat+info". Possible levels are numbers or:
"quiet"
"panic"
"fatal"
"error"
"warning"
"info"
"verbose"
"debug"

C>echo %ERRORLEVEL%
1

From the changelog in releases page, this problem seems to be rooted from pull #19025 (introduced in release 2019.01.30). The pull request added -loglevel "repeat+info" parameter to FFmpeg command line without checking whether it was supported by the FFmpeg version in use or not.

Running the same FFmpeg command line, without the problematic -loglevel "repeat+info" part, resulted in a successful remux and a watchable file; the remuxer also exited with code 0:

C>ffmpeg -y -i "file:ueoRSzCn4kA.480p+m4a128k.f135.mp4" -i "file:ueoRSzCn4kA.480p+m4a128k.mp4.f140" -c copy -map "0:v:0" -map "1:a:0" "file:ueoRSzCn4kA.480p+m4a128k.temp.mp4"
...
frame=36452 fps=464 q=-1.0 size=  142867kB time=00:24:16.10 bitrate= 803.8kbits/s
frame=36452 fps=464 q=-1.0 Lsize=  144068kB time=00:24:18.14 bitrate= 809.4kbits/s
video:120143kB audio:22783kB subtitle:0 global headers:0kB muxing overhead 0.798212%

C>echo %ERRORLEVEL%
0

I guess this was essentially what YouTube-DL originally did before the 2019.01.30 release.

Anyway, YouTube-DL should not be picky about which FFmpeg version(s) that users are able to use; expecially not for such a trivial reason like this.

Please investigate and fix.

YouTube-DL: 2019.03.09 (Win32)
FFmpeg: git c2dd5a1 "N-49610-gc2dd5a1" (5-Feb-2013, Win32/Zeranoe dynamically-linked)
System: Microsoft Windows XP Professional SP3

[TA40]

You should just upgrade your ffmpeg?
I mean it's from 2013, 6 years ago... ^^

[ghost]

@TA40 On top of that he's running Windows XP. I think this is one of those guys that expects everything to work but never wants to update anything on his machine. This issue isn't helping anybody but him.