Liaison statement
LS to IETF on Video Region-of-Interest (ROI)

State Posted
Posted Date 2015-07-16
From Group 3GPP-TSGSA-SA4
From Contact Susanna Kooistra
To Group avtext
To Contacts Keith Drage
Jonathan Lennox
CcBarry Leiba
Ben Campbell
Alissa Cooper
Audio/Video Transport Extensions Discussion List
Response Contact
Purpose For information
Attachments LS to IETF on Video Region-of-Interest (ROI)
1. Overall Description:
Regarding the new IETF draft in draft-huang-avtext-feedback-image-control-00,
3GPP SA4 would like to inform IETF that 3GPP has already specified a related
solution in 3GPP TS 26.114 as part of the Release 13 work item on “Video
Enhancements by Region-of-Interest (ROI) Information Signaling”. Attached is
the specification TS 26.114 v13.0.0, containing the adopted ROI signaling
framework described in clauses and 7.3.7.

In particular, the ROI signaling framework in 3GPP TS 26.114 is composed of
the following modes:

•	‘FECC’ mode, in which the receiving client uses the Far End Camera Control
(FECC) protocol based on ITU-T H.281 over H.224 to signal ROI information as a
sequence of ‘Pan’, ‘Tilt’, ‘Zoom’ and ‘Focus’ (PTZF) commands. 

•	‘Arbitrary ROI’ mode, in which the receiving client determines a specific
ROI and signals the corresponding ROI coordinates to the sender using RTCP
feedback messages.

•	‘Pre-defined ROI’ mode, in which the receiving client selects one of the
ROIs pre-determined by the sender and signals this ROI to the sender using
RTCP feedback messages. In this mode, the receiving client obtains the set of
pre-defined ROI coordinates from the sender during the SDP capability

Moreover, 3GPP TS 26.114 also specifies the ‘Sent ROI’ mode based on the use
of RTP header extensions, enabling the sender to signal to the receiver the
actually sent ROI corresponding to the video transmitted by the sender (which
may or may not agree with the ROI requested by the receiver).

Among these modes, we believe that the ‘Arbitrary ROI’ framework is well
aligned with the method described in
draft-huang-avtext-feedback-image-control-00. It would be desirable to ensure
that IETF considers 3GPP’s ROI signaling framework during the course of their
specification work, and that IETF and 3GPP coordinate on this matter to ensure
alignment of their specifications.

2. Actions:
3GPP SA4 kindly requests IETF to take the information above into account, and
maintain coordination with SA4 during the course of the development of
draft-huang-avtext-feedback-image-control-00 toward ensuring the alignment
between 3GPP and IETF specifications.

3. Date of Upcoming TSG-SA WG4 Meetings:
TSG SA WG4 Meeting #85	24 - 28 Aug 2015	Venue: Kobe, Japan
TSG SA WG4 Meeting #86	26 - 30 Oct 2015		Venue: San Jose Del Cabo, Mexico