Record videos for every single minute. Minimum requirements: Raspberry Pi Zero W and 12GB free space.

naive_cam.py

import picamera
from time import sleep
import datetime as dt

camera = picamera.PiCamera(resolution=(1024, 640), framerate=15)
camera.start_preview()
sleep(2)
camera.annotate_background = picamera.Color('black')
camera.annotate_text = dt.datetime.now().strftime('%Y-%m-%d %H:%M:%S')

while 1:
    file_name = dt.datetime.now().strftime('videos/%H_%M.h264')
    camera.start_recording(file_name)
    start = dt.datetime.now()
    while (dt.datetime.now() - start).seconds < 60:
        camera.annotate_text = dt.datetime.now().strftime('%Y-%m-%d %H:%M:%S')
        camera.wait_recording(0.2)
    camera.stop_recording()