说明：   图像预处理包括图像平滑、图像分割、二值化、图像形态学处理和轮廓提取。轮廓提取是使用八邻域边界跟踪算法。在手势的特征提取部分，使用边界傅立叶描绘子的手势特征提取算法。针对手势的识别，采用了基于 BP 神经网络的识别方法
(Image pre-processing, including image smoothing, image segmentation, binarization, morphological image processing and contour extraction. The contour extraction is eight neighborhood boundary tracking algorithm. Extract part of the characteristics of the gestures and use the boundary Fourier descriptors gestures feature extraction algorithm. Gesture recognition, the recognition method based on BP neural network)