Are Most Layer 2 Camera Discovery Tools Using A Common Protocol?

Dozens of manufacturer specific camera finders exist. Simple, lightweight and mostly bulletproof. Apparently they send out a broadcast ethernet frame and then listen back for a response with their OUI in the MAC address. The response contains the IP address of the camera.

Are these all homegrown discovery protocols? Or do they share a common mechanism, like LLDP or CDP?

Before I Wireshark it, it would be helpful to know what I might be seeing.