[Live-devel] Slow Edge Recording Playback/Export for missing Rate Control field ( Onvif/Hikvision )

[Gennaro Gallo]

Hi,

in Onvif and Hikvision specification for edge recording access there is an
extra header information to add in PLAY command:

Onvif Specification:

https://www.onvif.org/specs/stream/ONVIF-Streaming-Spec-v211.pdf

6.4.2
Rate-Control header field
This specification introduces the Rate-Control header field, which may be
either “yes” or “no”.
If the field is not present, “yes” is assumed, and the stream
is delivered in real time using
standard RTP timing mechanisms. If this field is “no”, the
stream is delivered as fast as
possible, using only the flow control provided by the transport to limit
the delivery rate.
The important difference between these two modes is that with
“Rate-Control=yes”, the server
is in control of the playback speed, whereas with “Rate-Control=no” the
client is in control of
the playback speed. Rate-controlled replay will typically only be
used by non-ONVIF specific clients as they will not specify
“Rate-Control=no”.


In the offical version of live555 this field is missing ( RequestRecord
class ) probably because it is a specific onvif field.

i think that a standard way to have this ( and other ) field could be the
adding of a generic extra header in RequestRecord class.

is it possible ?

Regards.
Gennaro Gallo

[Ross Finlayson]

In the offical version of live555 this field is missing ( RequestRecord class ) probably because it is a specific onvif field.
i think that a standard way to have this ( and other ) field could be the adding of a generic extra header in RequestRecord class.
is it possible ?

No.

Once again, if ‘ONVIF’ (or any other group) wishes to have their proposed extensions accepted by standards-conforming software such as ours, they need to submit them to the IETF (the group that defines the standards for RTSP).


Ross Finlayson
Live Networks, Inc.
http://www.live555.com/