Since plenty of digital files of music are available in the world wide web the search for melodies gains more and more importance. A mobile playback device like Apple's iPod is capable to store 5,000 titles easily. Up to now single pieces of music are only found in such a volume knowing the title or interpret of a tune. However, it is a typical problem that someone searching a tune is not aware of this information and knows only the melody.|
Technically speaking this problem is a search in a music database. If the user only knows the melody, the melody should be provided to the search system. A query-by-humming system (QBH-system) provides this possibility: the melody is hummed and the system presents a number of similar melodies as a result of this query.
The thesis explains the principles of QBH-systems and evaluates methods to test the functionallity of all single system parts. All important fundamentals regarding to the functions are explained. The chapter music and melody explains the meaning of the term melody and possible melody descriptions. An overview of existing melody and music search engines is given subsequenctly. A special chapter deals with multimedia standards for use with such systems. The role of signal processing for melody transcription is described in the monophonic and polyphonic case detailly. Measurements of melody similarity are shown in the following chapter. In the last chapter this thesis features especially the statitics of melody databases inside search engines.