problem description: now there is a pc project, which is expected to be automatically saved under the generated folder after taking photos when it is used as a project for the first time every day. If you have this folder, you do not have to regenerate it into
example: when you use this system for the first time, the name of the generated folder is 20181205_photo (a date-photo folder is automatically generated every day)
every day, the event of "first click" to take a picture will automatically trigger a check to see if the file exists, and create
if the folder does not exist.