路标识别，模式识别大作业，圆形检测；检测彩色路标，直方图均衡化，提取圆形路标，增强提取目标，二值化,提取路标中的指示图，中值滤波，平滑滤波，图像边框处理，链码生成及识别(The road sign recognition, pattern recognition operations, circle detection; detection of color signs, histogram equalization, extracting circular signs, enhanced extraction of the target, binarization, map and extract landmarks in median filtering, image smoothing, frame processing, chain code generation and recognition)