Definition
RTSP (Real Time Streaming Protocol) controls the delivery of audio and video in real time. In industrial practice it is the way an IP camera exposes its image to other software - a recorder, a video management system or an analytics engine.
Why the term comes up at all
When asked about adding AI analytics to existing surveillance, the first technical question is whether the cameras expose an RTSP stream. If they do, analytics can connect without replacing hardware.
The stream address usually looks like rtsp://user:password@camera-address/path. The path differs between manufacturers and is the most common cause of trouble during first connection.
Main and sub streams
Cameras usually expose two streams: a main one at full resolution and a heavily downscaled sub stream. Analytics normally uses the main stream, because small clothing details stop being recognisable in a downscaled image.
Network load is therefore counted in main streams. That is one reason analysis runs locally rather than after sending video off site.
Frequently asked questions
Does every IP camera support RTSP?
The vast majority do, although some consumer models block access or require enabling it in settings. Analogue cameras need a recorder that exposes the stream.
Does connecting analytics load the camera?
Every additional stream consumer adds load, but cameras usually handle several. With many consumers the image is pulled once and distributed onwards.
Is RTSP encrypted?
The protocol itself does not encrypt content. Plants use a separate surveillance subnet rather than relying on the protocol alone.