WISRD Research & Engineering Journal

Figure 31 . Photos taken at various times during the day. Clockwise from upper left: 9:20 am; 1:20 pm; 4:00 pm; 5:30 pm. 3.10.2 Automating Image Acquisition A timestamp is automatically added to each image. For example, a photo taken on July 7, 2021 at 5:30:01 pm is given the name DATE=2021-07-07_173001. Crontab scheduling is a file that allows scripts to be automatically executed at certain times. A schedule file (cron) takes photos at the times described above and places the images in the specific directories. Operating crontab is a four-step process: (1) The scripts need to know where they are sending the photos. (2) The automatic date and time file naming code is added to the scripts. (3) The path to the script that takes the pictures needs to be written in the cron. (4) The time they are taken needs to be specified and written. The command to access crontab is crontab -e A sample of these scripts is shown in Figure 32.

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