Convert Audio Tracks to .wma

convert_wma.sh

#!/usr/bin/env bash

which ffmpeg > /dev/null || { echo "REQUIRED: sudo apt-get install ffmpeg" >&2; exit 1; }
which ffprobe > /dev/null || { echo "REQUIRED: sudo apt-get install ffmpeg" >&2; exit 1; }

format=mp3
find . -type f | grep -i wma$ > tracklist.txt

#readarray -t files < tracklist.txt
declare -a tracklist
let i=0
while IFS=$'\n' read -r filename; do
    tracklist[i]="${filename}"
    ((++i))
done < tracklist.txt

num_tracks=${#tracklist[@]}
for ((i = 0; i < $num_tracks; i++)); do
    track=${tracklist[i]};
    output=${track%.wma}.$format
    probe=`ffprobe -show_streams "$track" 2>/dev/null`
    bitrate=`echo "$probe" | grep "^bit_rate" | sed "s:.*=\(.*\)[0-9][0-9][0-9][.].*:\1:" | head -1`
    ffmpeg -i "$track" -ab 128k "$output"
done