You can't convert mp3 to jpg image directly. MP3 file format is audio and jpg is bitmap image file format. But you are probably looking how to get the embedded picture from mp3 songs (album covers, interpret photos etc.).
You need some mp3 tag editor or some kind of music management software like Helium music manager or MediaMonkey that are designed to for editing of mp3 tags. With these tools users can easily edit information about mp3 song, export pictures and texts or other additional info from mp3 file.Open MP3 file Open JPG file
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