Design And Realization Of Piano Timbre Recognition And Electronic Synthesis System

Simulation of musical instruments is a cross disciplinary in both the fields of cross software engineering and music theory. In the past, due to the lack of professional knowledge, music professionals are unable to apply software engineering and mathematical methods to analyze musical acoustics principles at an in-depth level. On the other hand, software engineering researchers generally have very limited knowledge about music, and therefore, the study of software engineering related to music has been relatively weak all time through. In fact, under the technical support of signal processing and pattern recognition, it is now possible to reveal the mathematical secrets behind music, and thus improve our understanding of music. Applications of the software engineering technology in the field of music will bring new experience of hearing to human. It is in line with the idea of “Development of Cultural Power” proposed by the Chinese government, having great significance in the cultural and academic fields.The purpose of this study is to synthesize the piano timbre electrically by integrating software engineering and music theories. On the mathematical basis of the "Twelve-tone Equal Temperament" and the "Piano String Vibration Equation", this study conducted in-depth discussions and research about the piano timbre recognition and electronic synthesis methods. The main contents include:1. Based on the comparison among the life cycle method, the rapid prototype method and the object oriented method in software engineering, this study suggests that only the rapid prototype method may minimize the technical risk and shorten the construction period. MATLAB was used to build the rapid prototype and C#.net was used to develop the software product.2. The spectrum analysis method of short-time Fourier transform was applied to extract the characteristic matrix of piano timbre. The findings show that the timbre characteristic matrix of string instruments is different from that of tube or percussion instruments. Then, the relationship between the intensity attenuation and time was analyzed to obtain the amplitude envelope curve. It suggests that, as a hammered string instrument, the intensity attenuation curve of piano is different from that of the plucked string instruments and spring instruments. The timbre characteristic matrix and the amplitude envelope curve can be used to distinguish the differences between piano and other musical instruments, so as to realize the recognition of piano sound.3. This software performed matrix calculation on the timbre characteristic matrix of piano, and realized electronic synthesis of 25 harmonics for the piano timbre. The eventual simulation effect is better than the electronic organ based on “Cauchy function of the 5 harmonics" principle. Meanwhile, with the introduction of the amplitude envelope curve, the simulation effect is more close to real hammered string instruments.4. This software designed the middleware sound production technology with a three-layer structure. The finished software does not need to re-perform matrix operations for sound production, which reduces the load of CPU and improves the production efficiency. Thus, it is featured with pure timbre, stable amplitude, and small file size. The finished software does not contain any mathematical models or vocal parameters, so even if reverse engineering is conducted, the research achievements will not be disclosed.