I turned on logging using:
OpenNI::setLogMinSeverity(0);
OpenNI::setLogConsoleOutput(true);
and saw:
3774 INFO Log XnLog.cpp 349 New log started on 2019-11-25 09:57:11
3864 INFO Log XnLog.cpp 322 --- Filter Info --- Minimum Severity: VERBOSE
4044 VERBOSE OniContext OniContext.cpp 165 OpenNI 2.3.0 (Build 63)-Linux-Arm (May 13 2019 17:45:57)
4089 VERBOSE OniContext OniContext.cpp 259 Using '/usr/lib/OpenNI2/Drivers' as driver path
4112 VERBOSE OniContext OniContext.cpp 267 Looking for drivers at '/usr/lib/OpenNI2/Drivers'
4167 ERROR OniContext OniContext.cpp 279 Found no drivers matching '/usr/lib/OpenNI2/Drivers/lib*.so'
So I copied the files from OpenNI-Linux-Arm64-2.3.0.63/Redist/OpenNI2/Drivers/ to /usr/lib/OpenNI2/Drivers/. The Readme also says:
*for using with Astra Embedded S/Stereo S, please change the resolution in 'orbbec.ini' to 'Resolution=17' for Depth and IR streams
So I edited this in /usr/lib/OpenNI2/Drivers/orbbec.ini. Now I get:
3924 INFO Log XnLog.cpp 349 New log started on 2019-11-25 10:23:55
4010 INFO Log XnLog.cpp 322 --- Filter Info --- Minimum Severity: VERBOSE
4185 VERBOSE OniContext OniContext.cpp 165 OpenNI 2.3.0 (Build 63)-Linux-Arm (May 13 2019 17:45:57)
4230 VERBOSE OniContext OniContext.cpp 259 Using '/usr/lib/OpenNI2/Drivers' as driver path
4254 VERBOSE OniContext OniContext.cpp 267 Looking for drivers at '/usr/lib/OpenNI2/Drivers'
4547 VERBOSE OniContext OniContext.cpp 309 Loading device driver 'libOniFile.so'...
4588 WARNING xnOS XnLinuxSharedLibs.cpp 107 loading lib from: /usr/lib/OpenNI2/Drivers/libOniFile.so
6199 VERBOSE OniContext OniContext.cpp 309 Loading device driver 'libPSLink.so'...
6240 WARNING xnOS XnLinuxSharedLibs.cpp 107 loading lib from: /usr/lib/OpenNI2/Drivers/libPSLink.so
11412 WARNING DriverHandler OniDriverHandler.cpp 85 LibraryHandler: Couldn't find function oniDriverStreamConvertC2DCoordinates in libPSLink.so. Stopping
11539 WARNING OniContext OniContext.cpp 313 Couldn't use file 'libPSLink.so' as a device driver
11626 VERBOSE OniContext OniContext.cpp 309 Loading device driver 'liborbbec.so'...
11675 WARNING xnOS XnLinuxSharedLibs.cpp 107 loading lib from: /usr/lib/OpenNI2/Drivers/liborbbec.so
15571 INFO Log XnLog.cpp 349 New log started on 2019-11-25 10:23:55
15615 INFO Log XnLog.cpp 322 --- Filter Info --- Minimum Severity: VERBOSE
15645 VERBOSE xnUSB XnLinuxUSB.cpp 383 Initializing USB...
19162 INFO xnUSB XnLinuxUSB.cpp 412 USB is initialized.
OpenNI::initialize() = 0
OpenNI::enumerateDevices() = 0
which is better but still not successful. I then realised that I hadn’t reconnected the camera after copying the driver files so I did that and it worked.