I've been using a small script wrapped in an app (using Platypus) to convert my audio to ADPCM.
Today I updated that from using ffmpeg to using adpcm-xq (thanks to @mandra via @neven for the tip!)
Results are higher quality, compatible ADPCM audio files albeit with slightly longer conversion time.
usage
- run app and select files to process
or - drag and drop files onto the app icon
output
- folder
ADPCMnext to source files - 22KHz MONO, by default
options
hold modifier keys as you select files to change settings:
- CONTROL... sample rate 44KHz
- OPTION... sample rate 11KHz
- SHIFT... less look-ahead (faster but slightly worse results)
- CMD... output stereo
download
- ADPCM.app.zip (279.6 KB)
- Universal app for Intel (x86_64) and Apple silicon (arm64)
- uses adpcm-xq version 0.5 release
latest version
- adpcm-xq version 0.5 is much faster so have increase the quality to keep processing time roughly the same
- now uses zsh shell
- shows time taken for each file
notes
- app is signed by me, but I can only test on Sonoma - so no support on other versions of macOS, sorry
- you might need to right-click and choose Open, perhaps a couple of times, to get the app to launch
- uses macOS built-in tool afconvert to handle the sample rate conversion part of the process
screenshots
source code
#!/usr/bin/env zsh
echo "CONTROL... sample rate 44KHz"
echo "OPTION... sample rate 11KHz"
echo "SHIFT... less look-ahead"
echo "CMD... output stereo"
echo
optKeyDown=$(./keys option)
shiftKeyDown=$(./keys shift)
cmdKeyDown=$(./keys cmd)
controlKeyDown=$(./keys control)
# capslockKeyDown=$(./keys capslock)
RATE="LEI16@22050"
if [[ $optKeyDown -ne 0 ]]; then
RATE="LEI16@11025"
fi
if [[ $controlKeyDown -ne 0 ]]; then
RATE="LEI16@44100"
fi
if [[ $shiftKeyDown -eq 0 ]]; then
LOOK=9
else
LOOK=5
fi
if [[ $cmdKeyDown -eq 0 ]]; then
CHANNELS=1
else
CHANNELS=2
fi
echo "lookahead $LOOK && channels ${CHANNELS: -1:1} && sample rate ${RATE: -5:2}KHz"
echo
echo "Converting..."
echo
for file in "$@"; do
FILENAME=${file:t:r}
FOLDER=${file:h}
mkdir -p "$FOLDER/ADPCM/"
echo "• $FILENAME"
afconvert -f WAVE -d $RATE -c $CHANNELS "$file" "$FOLDER/ADPCM/.temp.wav"
{ time ./adpcm-xq -$LOOK -q -y "$FOLDER/ADPCM/.temp.wav" "$FOLDER/ADPCM/$FILENAME.wav"; } 2>&1 | awk '{print $6; exit}'
rm "$FOLDER/ADPCM/.temp.wav"
echo
done
echo
echo "done"
