surface direction meaning in English

表面方向

In 1980s , the theory of computer vision and the research on algorithm developed very fast , there came out many new concepts and new methods . formerly three dimension information was obtained via processing on two dimension image , while this time kinds of invariable features were obtained on the basis of gray scale / surface direction to perform area separation
进入八十年代，计算机视觉理论和算法研究发展迅速，新观点、新方法层出不穷，已从对二维图像进行处理获得三维信息，发展到从灰度表面方向出发提取各种不变的特征，进行区域分割。