LectureSIght (http://lecturesight.org) is an open source tracking solution for use in lecture capture systems. LectureSight makes use of real-time video analysis to direct a Sony VISCA, Axis VAPIX or ONVIF PTZ camera.
LectureSight in Action (Opencast Community Summit 2016)
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Opencast Community Summit
University of Cologne, March 14-16
LectureSight in action
Benjamin Wulff
Fraunhofer IAIS
Stephen Marquard and Corné Oosthuizen
University of Cape Town
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LectureSight is an open source real-time video tracking solution for PTZ cameras.
http://lecturesight.org (wiki, code, issue tracker, mailing list)
To run LectureSight, you need:
• a Linux Capture Agent with a GPU
• an overview camera (for example a webcam)
• a PTZ camera which supports VISCA (Sony), VAPIX (Axis) or ONVIF
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About LectureSight
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LectureSight:
Overview image
> detect changes
> detect objects
> direct camera (track objects)
> steer the camera
> send commands to
PTZ camera (IP / serial)
Capture Agent:
Record the PTZ camera image (IP / SDI / HDMI)
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How does LectureSight work?
4. ||
Our installations
LS in action…
What could possibly go wrong?
Production monitoring
Future plans
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LectureSight at the University of Cape Town
5. ||
Why? Blackboards, body language, gestures
Planned for up to 20 venues
Running in production in 4 venues (another 10 pending)
Hardware:
PTZ cameras: Axis V5915 (VAPIX), Vaddio ClearView HD-USB (VISCA)
Overview cameras: Logitech C930 webcam (USB), Raspberry Pi Cameras (IP)
USB active extension cables (up to 20m), ATEN UCE-260 USB 2.0 over CAT5 (up to 60m)
Ubuntu 12.04 Capture Agents running Galicaster 1.4.x with Nvidia GPUs (NV310+)
LectureSight scheduling is integrated with the Opencast / Galicaster calendar:
tracking starts and stops for scheduled recordings.
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LectureSight at UCT: Installations
8. ||
False positives in object detection
Lack of object persistence
Inability to distinguish presenter from background movement
projection on screen)
Inappropriate camera operator strategies (“always follow” not always right)
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What could possibly go wrong?
9. ||
Presenter is
tracked, but
another object
is incorrectly
detected, and
the camera
follows the
phantom object
for a while.
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False
positives
10. ||
When the presenter
stops moving, the
object times out after a
while.
A secondary object can
start being tracked
instead of the camera
remaining on the
primary target.
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Object
persistence
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Typically too much camera movement from:
rapid movement of a single presenter
too many targets (start/end of lecture)
Rather zoom out (“if in doubt, go wide”) or stop tracking.
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Inappropriate camera operator strategies
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Has LectureSight started up correctly?
Is it tracking, or idle (waiting for an
event)?
telnet to your LS instance on port 2501
(osgi.shell.telnet.ip=x.x.x.x)
Get status with “lb”, “scr:list”, and
“scheduler:status”
Script and graph
To do: snapshot / dashboard of overview
camera images
https://opencast.jira.com/projects/LS/issues/LS-153
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Production monitoring
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Improve object tracking (face detection, object persistence, fewer false positives)
More capable camera operator (pan/tilt/zoom, wider range of strategies)
Instrumentation / statistics to give insight into tracking performance and quality
Improved GUI and easier calibration
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UCT’s Road Map / Wish List for LectureSight