Typically, each frame is transmitted uncompressed in RGB or YUV or compressed as JPEG.
Some cameras, such as mobile-phone cameras, use a CMOS sensor with supporting electronics "on die", i.e.
You can’t even go in and look at past video recordings.
RELATED: The good news, though, is that it at least sends you a notification when your camera goes offline, accompanied by an image of what the camera last saw before it lost its connection.
Image sensors can be CMOS or CCD, the former being dominant for low-cost cameras, but CCD cameras do not necessarily outperform CMOS-based cameras in the low-price range.
If you’re lucky enough to own a Wi-Fi cam that can also record video locally to an attached USB device or SD card, then it’s likely that the camera can still record footage even without a Wi-Fi connection. The cameras are genuinely wireless (meaning battery-powered and a Wi-Fi connection), but they directly connect to an Arlo base station, and then that base station connects to your router.
You can plug a USB flash drive into the base station to record video locally, and whenever your Wi-Fi goes out unexpectedly, your Arlo Pro camera will still record whatever it needs to but will save it to the USB flash drive.
Various lenses are available, the most common in consumer-grade webcams being a plastic lens that can be manually moved in and out to focus the camera.
Fixed-focus lenses, which have no provision for adjustment, are also available.