High speed acquisition system of photo-colorimetric images to record and to model human visual signal

摘要

Various problems in different domains are related to the operation of the Human Visual System (HVS). This is notably the case when interest turns to the driver's visual perception and road safety in general. As we know, 90% of the information used by a driver is supplied to him by his visual system. That's why the Laboratoire Regional des Ponts et Chaussees d'Angers has developed a human visual signal capture system. This system is based on a CCD video camera calibrated for luminance and chrominance which are the two physical magnitudes that make up the human visual signal. The first phase in the development is to adapt the spectral response of the optical system to the spectral characteristics of the human eye. Once the camera is adapted the second stage is calibration. This consists in transforming the graylevels registered by the camera into values of luminance and chrominance. The innovative feature of this system is the ability to record a single image containing the entire set of information carried by the visual signal. The framerate is 10 frames per second which allows the camera to be carried inside a vehicle and to record images of road scenes exactly as the driver has actually perceived them. After recording, vision algorithms can be applied to these images in order to reproduce the physiological processes which take place on the retina or in the brain. These tools can then be used to evaluate visibility levels of roadway infrastructure, of public lighting, or the saliency of objects.