arr[i]
{"GETID3_VERSION":"1.9.15-201709291043","error":["Could not open \"\" (!is_readable; !is_file; !file_exists)"]}
keys
["GETID3_VERSION","error",null]
Key:GETID3_VERSION
Val:"1.9.15-201709291043"
11

Key:error
Val:["Could not open \"\" (!is_readable; !is_file; !file_exists)"]
11


{"title":"","artist":-1,"album":-1,"album_artist":-1,"replaygain_track_gain":-1,"sort_title":"","playtime_seconds":-1,"filesize":-1,"encoding_tool":-1,"encoding":-1,"codec":-1,"0":"","1":-1,"2":-1,"3":-1}