afconvert and avconv performance
SoftwareMy Rubenerd Show podcast episodes are produced with a series of shell scripts to save me time and effort, so I’m always looking for ways to optimise them.
Today I learned about Apple’s afconvert utility. The manpage may as well have been written by GNU given its lack of useful info, but “-h” tells you all you need to know.
Currently I use avconv (previously ffmpeg) to convert CAFs from my iTelephone to an intermediate format. This is then rendered as FLAC for archival purposes, and MP3 for the podcast feed:
$ avconv -i "source.caf" "output.aiff"
Through some digging, the afconvert equivilent is:
$ afconvert -f caff -d BEI16 "source.caf" "output.aiff"
But how do they stack up? I ran these three times on the same 201.1MiB source file using afconvert in macOS Sierra, and the latest avconv from Homebrew:
| Pass | afconvert | avconv |
|---|---|---|
| 1 | 0.416s | 1.189s |
| 2 | 0.577s | 1.339s |
| 3 | 0.416s | 1.302s |
The results from this (albeit limited) test are clear, afconvert is faster. Whether I’d notice a second or two difference is another question, but I’ll be adjusting the scripts to preference afconvert when available.
