Content-based MIDI Music Retrieval and Computer-aided Composition Based on Musical Whistling Hung-Cche Shen* Chung-Nan Lee+ ABSTRACT In this dissertation, we have focused on the research of content-based MIDI music retrieval and computer-aided composition based on musical whistling. For MIDI music retrieval, a prototype system called ¡§Whistle-for-Music¡¨ is developed. This system enables users to retrieve MIDI format music by whistling a melodic fragment. It consists of three essential components which are query processing, MIDI preprocessing and an approximate search engine. For query processing, we have achieved a real-time and robust whistle-to-MIDI converter. For MIDI preprocessing, the extracted features from MIDI files contain individual, local and global melodic descriptions. In order to match a querying pattern with target, we extend an existing search engine into a fast approximate melodic matching engine. There is a systematic evaluation of ¡§Whistle-for-Music¡¨ system. The performed experiments include ¡§Query turnaround time¡¨, ¡§Unique prefix searching¡¨, ¡§Error density vs. match rank percent¡¨ and ¡§Statistics of global descriptions¡¨. The results show that careful measurement and objective comparisons can lead us to know the scaling trend about query and target. For computer-aided composition, a system called ¡§Whistle-to- Music¡¨ is presented. The ¡§Whistle-to-Music¡¨ system can ease the melody input and musical composition. Firstly, our ¡§Whistle-to-MIDI¡¨ transformation is to translate a whistled tune into a sequence of notes, which are defined by onset, duration, velocity and note pitch. This ¡§Whistle-to-MIDI¡¨ is a relative melody transcription since we apply ¡§pitch templates¡¨ and ¡§rhythm templates¡¨. Based on the given melodic motives, we propose the templates of melodic forms and harmonic tables for the tasks of motive development and automatic harmonization. We demonstrate that the proposed melodic forms templates can successfully produce various formal songs from one or few bass motives. The harmonic tables allow us to produce classic-style harmonization based on three theories. The process of ¡§Whistle-to-Music¡¨ system is described by giving examples of melody transcription, motive development and demonstrating the resulting music from automatic harmonization. In automatic harmonization, we demonstrate that the proposed harmonic tables can successfully produce a piece of well-formed harmonization from a variety of whistled tunes. * Author +Advisor