## Electron devices, Communication technology, Information processing technology

## Technology of interpolating high frequency signal lost in compression

Keyword: Audio signal regeneration equipment, Interpolation of High region signal, High quality sound

Organizations Involved

○ Yasushi Sato, Professor, Human Life IT Development Center, Kyushu Institute of Technology

○ Hitoshi Inaba, Mobile Entertainment Division, Toshiba Corporation Digital Media Network Company

○ Shigehiro Kakumoto, Headquarters, Global Sales & Marketing Management, Hitachi Maxell Ltd.

Prof. Sato

## 【Abstract】

By using harmonic interpolation technology developed by Human IT development center of Kyushu Institute of Technology, Toshiba Corporation put a portable music player into the market by the brand name of “Gigabeat” and Hitachi Maxell Ltd. put a head phone system into the market by the brand name of “Vraison”. Both obtained high evaluation with its high quality sound by critics.

## [Summary of the technology transfer]

## Technological Impact

The portable music player has spread but its sound is deteriorated due to missing of high region signal by compression like MP3. KIT developed basic technology to regenerate sound from middle range to high range fascinatingly and comfortably to an ear by interpolating the missed signal by original algorithm based on harmonic interpolation.

## Market Impact

Companies industrialized the technology and their products are now in the market. And their business is continuing and expanding. Toshiba put a new revised model in the market and Hitachi Maxell's "Vraison" was awarded Special Prize (Technology Development Prize) of AUDIO GOOD EQUIPMENT PRIZE 2007.

## ●Social Impact

This high quality sound regenerating technology can be applied to various audio products and was already applied to different kinds of product as differentiation technology by two or more companies. Thus, this technology contributed to the creation of high value added products of new concept. Furthermore it is also expected to be applied to other products like audio equipment and TV etc.

## ●Special Features of the Collaboration

The researcher of the university promoted a new type (MODE II) of Industry-Academia collaboration in which the researcher did research work predicting the needs of the market, making basic patent application, and then proposed its application to a company. Taking this as a successful model case, this type of collaboration is expected to spread.

## Project Background

In this case the researcher of the university planned the research for the purpose of technology transfer from the beginning. And the researcher proposed the development of the application product s to a company using the technology.

## Funding History

1. University’s fund was used for basic technology development.

2. Sponsor’s fund was for application development.

3. Other governmental competition fund was not used.

## I ntellectual property protection

Patent Application: Domestic 6, PCT 2 Title: "High frequency signal interpolation method and its equipment"

## Products adopted the high quality sound technology

## Hitachi Maxell『Vraison』

Toshiba『Gigabeat』

## Turning point in the Project

An unexpected technical problem may occur in the product development in a company. It may be the fundamental success factor that the researcher of a university corresponded to such problem faithfully in cooperation with the person of a company. Moreover, it was useful to have a venture company interpolated the function between the university and the company.