support metadata plugins

bin/mtag/README.md

@@ -5,4 +5,4 @@ some of these rely on libraries which are not MIT-compatible
 * [audio-bpm.py](./audio-bpm.py) detects the BPM of music using the BeatRoot Vamp Plugin; imports GPL2
 * [audio-key.py](./audio-key.py) detects the melodic key of music using the Mixxx fork of keyfinder; imports GPL3
 
-run [`install-deps.sh`](install-deps.sh) to build/install most dependencies required by these programs
+run [`install-deps.sh`](install-deps.sh) to build/install most dependencies required by these programs (supports windows/linux/macos)

bin/mtag/install-deps.sh

@@ -4,7 +4,7 @@ set -e
 
 # install dependencies for audio-*.py
 #
-# linux: requires {python3,ffmpeg,fftw}-dev py3-{wheel,pip} py3-numpy{,-dev} vamp-sdk-dev
+# linux: requires {python3,ffmpeg,fftw}-dev py3-{wheel,pip} py3-numpy{,-dev} vamp-sdk-dev patchelf
 # win64: requires msys2-mingw64 environment
 # macos: requires macports
 #
@@ -174,7 +174,8 @@ install_keyfinder() {
 	pypath="$($pybin -c 'import keyfinder; print(keyfinder.__file__)')"
 	for pyso in "${pypath%/*}"/*.so; do
 		[ -e "$pyso" ] || break
-		patchelf --set-rpath "${libpath%/*}" "$pyso"
+		patchelf --set-rpath "${libpath%/*}" "$pyso" ||
+			echo "WARNING: patchelf failed (only fatal on musl-based distros)"
 	done
 	
 	mv "$pypath"{,.bak}