[Youtube] [Convert to AAC] No effect when using -postprocessor-args "-r 44100" for ffmpeg

[ddelange]

Checkboxes

• I've verified and I assure that I'm running youtube-dl 2018.07.04

• At least skimmed through the README, most notably the FAQ and BUGS sections

• Searched the bugtracker for similar issues including closed ones

• Checked that provided video/audio/playlist URLs (if any) are alive and playable in a browser

• Bug report (encountered problems with youtube-dl)

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Aim

Convert any video to the highest quality audio output available (in 256kbps AAC), with a sampling rate of 44.1 kHz.

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Issue

Everything is set up accordingly, and the output quality is as expected (frequencies up to 22 kHz for each channel), in a 48 kHz file. However, additionally passing -postprocessor-args "-r 44100" does not have any effect on the output file.

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Verbose output

URL used for testing with opus audio format available: https://www.youtube.com/watch?v=4FwpwFDuZbk

The line starting with ** shows that the sample rate argument is indeed passed to ffmpeg.

youtube-dl -v --geo-bypass --postprocessor-args "-r 44100" -x -f "bestaudio[acodec=opus]/bestaudio/best" --audio-format m4a --audio-quality 256 --no-playlist -i -o "~/Music/youtube-dl/%(title)s.%(ext)s" --download-archive "~/Music/youtube-dl/Downloaded.txt" --add-metadata --metadata-from-title "%(artist)s - %(title)s" --embed-thumbnail https://www.youtube.com/watch?v=4FwpwFDuZbk
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: [u'-v', u'--geo-bypass', u'--postprocessor-args', u'-r 44100', u'-x', u'-f', u'bestaudio[acodec=opus]/bestaudio/best', u'--audio-format', u'm4a', u'--audio-quality', u'256', u'--no-playlist', u'-i', u'-o', u'~/Music/youtube-dl/%(title)s.%(ext)s', u'--download-archive', u'~/Music/youtube-dl/Downloaded.txt', u'--add-metadata', u'--metadata-from-title', u'%(artist)s - %(title)s', u'--embed-thumbnail', u'https://www.youtube.com/watch?v=4FwpwFDuZbk']
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2018.07.04
[debug] Python version 2.7.13 (CPython) - Darwin-12.5.0-x86_64-i386-64bit
[debug] exe versions: ffmpeg 3.4.1, ffprobe 3.4.1
[debug] Proxy map: {}
[youtube] 4FwpwFDuZbk: Downloading webpage
[youtube] 4FwpwFDuZbk: Downloading video info webpage
[youtube] 4FwpwFDuZbk: Downloading thumbnail ...
[youtube] 4FwpwFDuZbk: Writing thumbnail to: /Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).jpg
[debug] Invoking downloader on u'https://r4---sn-4g5e6nez.googlevideo.com/videoplayback?source=youtube&sparams=clen%2Cdur%2Cei%2Cgir%2Cid%2Cinitcwndbps%2Cip%2Cipbits%2Citag%2Ckeepalive%2Clmt%2Cmime%2Cmm%2Cmn%2Cms%2Cmv%2Cpl%2Crequiressl%2Csource%2Cexpire&requiressl=yes&fexp=23709359&fvip=4&clen=3150446&gir=yes&dur=188.421&lmt=1523381040170633&key=yt6&mime=audio%2Fwebm&ei=t7hAW7X2NYH9gAfi44zwAw&c=WEB&expire=1530989848&signature=4D6B010BDBFD0C384FF06BF7F4B193A17F6DBC3B.3A51301836DC09EA5E26C06945F2B339DDEF6013&initcwndbps=390000&mn=sn-4g5e6nez%2Csn-5hnekn7l&itag=251&mm=31%2C26&ip=185.220.70.131&ipbits=0&id=o-AEGmq2Z1TA9CNuf98ynRbrn_hI3EV5rxZA-6f9uq286K&pl=24&keepalive=yes&ms=au%2Conr&mv=m&mt=1530968148&ratebypass=yes'
[download] Destination: /Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).webm
[download] 100% of 3.00MiB in 00:01
[fromtitle] parsed artist: Re-Style
[fromtitle] parsed title: Get It Crackin (Sefa Remix)
[debug] ffmpeg command line: ffprobe -show_streams 'file:/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).webm'
[ffmpeg] Destination: /Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).m4a
**[debug] ffmpeg command line: ffmpeg -y -i 'file:/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).webm' -vn -acodec aac '-b:a' 256k '-bsf:a' aac_adtstoasc -r 44100 'file:/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).m4a'
Deleting original file /Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).webm (pass -k to keep)
[ffmpeg] Adding metadata to '/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).m4a'
[debug] ffmpeg command line: ffmpeg -y -i 'file:/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).m4a' -vn -acodec copy -metadata 'comment=[removed comments for readibility]' -metadata 'artist=Re-Style' -metadata 'title=Get It Crackin (Sefa Remix)' -metadata 'date=20180410' -metadata 'purl=https://www.youtube.com/watch?v=4FwpwFDuZbk' -r 44100 'file:/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).temp.m4a'
[atomicparsley] Adding thumbnail to "/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).m4a"
[debug] AtomicParsley command line: AtomicParsley '/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).m4a' --artwork '/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).jpg' -o '/Users/David10.8/Music/youtube-dl/Re-Style - Get It Crackin (Sefa Remix).temp.m4a'

[dstftw]

-r is video option. Audio option is -ar.