mexDDGrab.dll　一定要将其放在WORK目录下。以下文件也一样。 mmread 可读取各种视频格式的文件，用法在M文件中。 avermatrix　提取静止的背景。 frame2bmp　将视频帧存为BMP格式。 show 仔细阅读，可单步输入MATLAB命令窗口运行。-mexDDGrab.dll must put WORK directory. Following the same document. mmread can read a variety of vide

通过读取视频中连续几帧图像，利用差分法获得目标图像-The target image is obtained by using the inter frame difference method, through the reading of several consecutive frames in the video.

通过读取视频中背景图像和其中一帧图像，利用背景差分法获得目标图像-By reading the background image and one frame image, the target image is obtained by using the background difference method.

通过读取视频中连续几帧图像，利用帧间差分法检测得到目标图像-The target image is detected by using the inter frame difference method.