Shigeki Nagaya

Fast Method for Face Detection Based on the Characteristic of Cascade Classifier

We propose a fast method of face detection that is based on the characteristics of a cascade classifier that is called a cascade step search (CSS). The proposed method has two features. First is a gradual classification that uses only a few layers of the cascade classifier to estimate the face-likelihood distribution. Second is an efficient search that uses the face likelihood distribution. The search is operated at intervals that are optimally changed according to the likelihood. This reduces the number of sub-windows that must be processed. The face-likelihood on the image window exposes the likelihood near the window and the next scaled one. These features can reduce the costs of classifications in the face detection process. Our experiments on face detection show that the proposed method is about five times faster than the traditional searches and maintains a high detection rate.

A proposal of novel information architecture-open cooperative work space

We propose a novel information integration architecture for a man-machine interface and a new CSCW system called open cooperative work space (OCoWS) for its implementation. The architecture gives system users the advantage of a cooperative work space, in the style of an ordinary meeting by means of human sensing techniques as the system input interface and the integration of their results in several levels. As a result, users can dedicate themselves to mutual understanding among meeting members with no awareness of direction to the CSCW system.

An active microphone method for speech recognition systems

We propose a method to recognize human speech without the restriction that the speaker should be close to the microphone for the multiple modal interface. This method has the following features: 1) to control the microphone directivity for improvement of S/N ratio by using the speakers position estimated by the result of gesture recognition, 2) to compose the impulse response of the transfer characteristic between speakers and microphones into reference data of the recognition system. We describe the active microphone method in detail, and show its effectivity through several experiments. Then, we discuss the results.