FLAC to ALAC converter. Requires Mac OS X and `flac` binary installed (ie. via Homebrew: `brew install flac`).

flac2alac

#!/usr/bin/env bash
set -e

convert_to_alac() {
  flac="$1"
  aiff="${flac%.*}.aiff"
  alac="${flac%.*}.m4a"

  flac -s -d --force-aiff-format -o "$aiff" "$flac"
  afconvert -f m4af -d alac "$aiff" "$alac"
  rm "$aiff"
}

if [ $# -ne 1 ]; then
  echo "usage: $0 dir"
  echo "requirements: Mac OS and flac installed"
  exit 1
fi

for file in "$1"/*.flac; do
  echo -n "."
  convert_to_alac "$file"
done

echo " done"

You may also use iDealshare VideoGo to convert FLAC to ALAC without quality loss.

It also helps to convert ALAC to FLAC and convert between FLAC, ALAC, M4A, WAV, MP3, AAC, WMA, OGG, OPUS etc

It also helps to extract FLAC, ALAC from video files or convert between video formats.

Here is the easy guide https://www.idealshare.net/audio-converter/flac-to-apple-lossless.html

I don't think you need Homebrew or to install anything... here's how I do it on Mojave and Catalina:

export IFS=$'\n'
for x in `ls *.flac`; do afconvert -v -f m4af -d alac $x ${x%flac}m4a; done

@alvarow

absolutely perfect. Had no idea afconvert just existed like that! Thank you.

It's very handy, thanks!

For anyone who may need it: I've also made another version based on ffmpeg which also downsamples the audio to 16bit / 44100kHz, otherwise my iPod was stuttering when playing files with 32bit sample size 😬 It's here: https://gist.github.com/pltb/244899d900a1b0305467f50e32133cc3

(I couldn't make flac or afconvert downsample the audio, and was too lazy to dig deeper, so just used ffmpeg 😅 )