인코더나 컨버터를 사용하면 됩니다.

굼뱅이님, 인코더 컨버터가 어떻게 생겼으며 어데서 구하는지요?

download "switch"  go google and "switch" download it ... it is freeware..

Thank you remada, but my music is "MPEG4" which is not included in that "switch" software capability. Hope you can find the way to change that MPEG4 music into MP3 format file? Thank you again!

http://kin.naver.com/qna/detail.nhn?d1id=1&dirId=10204&docId=64045824&qb=bXBlZzTrpbwgbXAz66Gc&enc=utf8§ion=kin&rank=10&search_sort=0&spq=0&sp=1&pid=gKt0wsoi5URssayBeKVsss--450029&sid=TMAJGk4BwEwAAHmfDKg

돌팔이님, 감사합니다..마는 네이버에 가입을 해야하고 가입신청이어려워서(외국인으로되있어서) 사용불가하네요....

구글해보니 많이 나오네...
http://www.google.com/search?hl=ko&source=hp&q=convert+mp4+to+mp3&aq=0&aqi=g7g-m3&aql=&oq=convert+mp4+to+mp&gs_rfai=CD06UbRbCTMq9LKKYoATG_73yBwAAAKoEBU_Q9R72