Automatic Music Composing System Based on Music Theory and Existing Melodies

本論文基於一些數學方法與樂理知識重組現有歌曲旋律片段達到自動譜曲的效果；我們收集了200多首歌曲的片段歌詞，及對應的簡譜與音長資訊，建立旋律資料庫；主要流程為使用者輸入一段文字後，系統利用一些基本的數學方法，篩選與輸入文字最相符之單首或多首歌曲組成的旋律片段；接著利用既有樂理知識所歸納出的原則，包括樂句順序、重要音與和弦進行，將這些片段連接起來；最後將旋律與輸入文字進行比對與調整，使兩者能夠完全相符，即可輸出結果旋律；論文最後將不同方法所譜出的旋律音檔以問卷形式請人評估優劣。We propose a handy automatic composing system using some math methods and music theory knowledge to compose melodies automatically. To create the database of melodies, we first collect the information of melody clips, including lyrics, corresponding numbered musical notations and tones duration, from over 200 songs. The main procedure of our system goes as follows. After the user inputs a bunch of characters, we will use some basic math methods to find out one or multiple melody clips which match the input best and combine these melody clips by certain music theory knowledge, such as the order of sentences, important tones and chord progression. We then move to adjust the obtained melody clips according to the difference between the number of characters and the number of tones to pursue the total match and output the resultant melody. To check the performance of our system, we set up a questionnaire which includes the resultant melody sound files of each method and distribute it out for listeners to judge if the resultant melodies are harmonic