What is the difference between ONVIF Profile S and Profile T?
ONVIF Profile S (released 2011) covers basic IP video streaming, PTZ, and audio over H.264 and MJPEG. Profile T (released 2018) adds H.265 (HEVC), motion alarms, bidirectional audio, on-camera analytics metadata, and imaging-setting control. Profile T is a superset for video; almost every camera made after 2019 supports both. For AI integration, Profile T cuts bandwidth by 35 to 50% via H.265 and exposes analytics events natively.
The ONVIF profiles family ensures cameras and VMS, NVR, and AI platforms from different vendors can interoperate. Each profile is a fixed feature set, certified by ONVIF, that a vendor either fully supports or does not.
Side-by-side feature comparison
| Capability | Profile S | Profile T |
|---|---|---|
| Year introduced | 2011 | 2018 |
| H.264 streaming | Yes | Yes |
| H.265 / HEVC streaming | No | Yes |
| MJPEG | Yes | Yes |
| PTZ control | Yes | Yes |
| Audio streaming | One-way | Two-way |
| Motion alarms | No (vendor-specific) | Yes (standardised) |
| Tampering alarms | No | Yes |
| Imaging settings (exposure, WDR) | Limited | Full |
| On-camera analytics metadata | No | Yes |
| Privacy masks | No | Yes |
Why Profile T matters for AI
Three reasons. First, H.265 reduces bandwidth roughly 35 to 50% versus H.264 at equal visual quality — a 32-camera 1080p site drops from about 96 Mbps to 48 to 62 Mbps of LAN traffic. Second, on-camera motion or tamper alarms let the AI server skip frames where nothing changes, cutting GPU load up to 40%. Third, standardised analytics metadata (bounding boxes from a camera's built-in detector) can pre-filter events before they reach a heavier model.
When Profile S is enough
- Small sites under 16 cameras where bandwidth is not a constraint.
- Workloads that ignore on-camera events and run all detection server-side.
- Existing camera estate with no plan to refresh.
How to check which profile your camera supports
- Read the product datasheet — ONVIF profile support is always listed.
- Confirm with the ONVIF Conformant Products database (search by model).
- Test with the free ONVIF Device Manager or a tool like ONVIF Device Test Tool.
- Check firmware — older firmware may report Profile S only even on newer hardware.
Other ONVIF profiles you may meet
- Profile G — recording and storage (NVRs).
- Profile A — access control configuration.
- Profile C — access control (door events).
- Profile M — analytics metadata transport (released 2021, builds on T for richer metadata).
For integration steps, see integrating AI with existing CCTV.
