（1）　　开始预览：连接良田高拍仪设备后，打开预览图像界面。（开始预览按钮点击后颜色下拉列表和旋转角度下拉列表才会有值）

（2）　　停止预览：关闭预览图像界面。

（3）　　拍照：扫描当前图像。

具体功能描述请参照ScanCtrl控件使用说明文档-(1) Start Preview: Connecting the fertile high shot meter device, open the preview image interface. (Click on the preview button to start the color drop-down list, and rotation angle will have a drop-down list value) (2) Stop Preview: Close preview image interface. (3) photos: Scan the current image. Please refer to the specific features described ScanCtrl control the use of documentation