Cameras play a much larger role in our society than we sometimes realize. Just think of all the cameras for surveillance purposes, in the process industry, the medical sector and traffic. If the weather conditions are not optimal, however - e.g. rain or fog - the performance of these cameras decreases.
Even if modern cameras are able to distinguish up to 4,000 grey levels, the human eye will stop at 80. This means that under adverse weather conditions contrast becomes worse, in which case the operator will have to work with suboptimal images. In view of the function of many of these cameras - security, surveillance, etc. - this is not a desirable option. TNO developed a real-time ASIC contrast enhancer: the VISTA01. The VISTA01 will enable the operator to adjust the contrast of black and white video images - in general or user-defined - in compliance with an own Area of Interest (AOI). Under any condition.
For each video image the contrast is evaluated using a grey value histogramme. The MOVE microprocessor will then read the contrast of the histogramme and calculate the parameters for the high-speed video path. The contrast-enhancing algorithms may be adjusted through special software for optimal performance under any condition, as well as for any camera.