extractaudio:
Usage: extractaudio archive_name (c)
Use c as the second argument if the archive has mojibake filenames.
Example: extractaudio RJ100000.zip
Example: extractaudio RJ100001.zip c

#!/usr/bin/bash
archive=$1
method=$2

dirname=$(echo "$archive" | cut -f 1 -d '.') #Get the name of the archive without file extension
mkdir $dirname

if [ "$method" = "c" ]
then
    LC_ALL=C 7z x -o"$dirname" $archive
else
    7z x -o"$dirname" $archive
fi

fixencoding $dirname
convertaudio $dirname



fixencoding:
#!/usr/bin/bash
dirname=$1
convmv -f shift-jis -t utf8 --notest -r $dirname #Fix filenames. Will skip filenames that are already utf8.

shopt -s globstar

for txtfile in $dirname/**/*.txt; do
    currentencoding=$(file --mime-encoding "$txtfile" | cut -f 2 -d ':')
    if [ "$currentencoding" = " unknown-8bit" ] #Only convert txt files with unknown-8bit encoding. This prevents utf8 files from being corrupted.
    then
        iconv -f SHIFT-JIS -t UTF-8 "$txtfile" -o out.txt
        mv out.txt "$txtfile"
    fi
done



convertaudio:
#!/usr/bin/bash

dirname=$1

shopt -s globstar

for wavfile in $dirname/**/*.wav; do
    ffmpeg -i "$wavfile" -acodec libopus -b:a 128000 -vbr on -compression_level 10 "${wavfile%.wav}.ogg"
    rm "$wavfile"
done

for flacfile in $dirname/**/*.flac; do
    ffmpeg -i "$flacfile" -acodec libopus -b:a 128000 -vbr on -compression_level 10 "${flacfile%.flac}.ogg"
    rm "$flacfile"
done