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Useful built-in macOS command-line utilities

(weiyen.net)
700 points yen223 | 3 comments | 06 Nov 24 05:51 UTC | HN request time: 0.001s | source
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daneel_w ◴[06 Nov 24 16:42 UTC] No.42064988[source]▶
A couple more:

    afconvert(1) - an audio file format converter, which includes Apple's superior AAC codec from the Core Audio framework

    diskutil(8) - tons of tools for fixed and removable storage
Examples:

    afconvert in.wav -o out.m4a -q 127 -s 2 -b 160000 -f m4af -d 'aac '

    mb=300; diskutil eraseVolume APFS myramdisk `hdiutil attach -nomount ram://$((mb*2048))`
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hk1337 ◴[06 Nov 24 18:03 UTC] No.42066466[source]▶
How does that compare with ffmpeg? The arguments seem about the same.
replies(2): >>42067194 #>>42067397 #
1. krackers ◴[06 Nov 24 18:45 UTC] No.42067194[source]▶
afcovert uses the superior inbuilt AAC converter. FFmpeg can do this as well with the right arguments but you have to dig them up and the quality is capped to a lower value than you can get with afconvert.
replies(1): >>42068952 #
2. anthk ◴[06 Nov 24 20:37 UTC] No.42068952[source]▶
There's no reason to use AAC when we have both OPUS and FLAC.
replies(1): >>42069139 #
3. daneel_w ◴[06 Nov 24 20:49 UTC] No.42069139[source]▶
I have three reasons: when using a good encoder (Core Audio, FDK or Nero) it's a quality-wise better lossy format than MP3, it's smaller than FLAC which matters for storage footprint, and unlike Opus and FLAC it's supported pretty much everywhere. At some point Opus will reach the same level of adoption and that's the point where I'll make the switch from AAC, because Opus is evidently a better lossy encoder per same bitrate.