模式识别中有关特征提取的那部分（链码），还有灰度特征。-Feature extraction in pattern recognition, that part of the (chain code), and gray feature.

matalb链码代码，从某一起点开始沿曲线观察每一线段的走向并用相应的指向符来表示，结果形成一个数列。-matalb chain code codes, a starting point along the curve to observe each segment with the corresponding point symbols to represent, resulting in a number of columns.