Enumeration of camera - issue with multiple instances of the same camera!

[harshakasi]

I am trying to use the USB 3.0 1280-54um camera through pypylon on my Mac OX 10.15 (Catalina). This error has nothing to do with the Mac OSx latest update from 10.14 (Mojave) to 10.15 as the error was pre-existing in the 10.14 revision.

Based on the examples for camera access and functioning provided in the python code examples, I am doing the following in my __main__:

self.tlFactory = pylon.TlFactory.GetInstance() # instantiate an object self.devList = self.tlFactory.EnumerateDevices() # enumerate devices

At this point, although there is only one Basler camera 1280-54um connected to the USB port, the devList object is assigned a list of two devices both containing the same serial number.

A snapshot of the content within devList as obtained from Visual Code Editor is: 0:<pypylon.pylon.DeviceInfo; proxy of <Swig Object of type 'Pylon::CDeviceInfo ' at 0x118614f30> > 1:<pypylon.pylon.DeviceInfo; proxy of <Swig Object of type 'Pylon::CDeviceInfo ' at 0x118614ea0> > len:2

@basler-oss, could you please provide a resolution for the same at the earliest?

I am trying to make my app work on python and at the transport layer somehow two instances of the same device get created within the EnumerateDevices() function.

[thiesmoeller]

if you print out the device-info [ e.g. model and serial number ] of the two devices you see: are they really the same? As a quick workaround the method CreateFirstDevice() on TlFactory will pick the first on any list

[thiesmoeller]

is the issue still present with most current release?

[harshakasi]

is the issue still present with the most current release?

Yes it is still present in the current release Version 1.7.2 and probably why in the sample code (startup.py) snippet, they suggest using the following instruction to create a camera object pertaining to the connected device:

camera = pylon.InstantCamera( pylon.TlFactory.GetInstance().CreateFirstDevice())

Hope that answers your query.

Thanks!

[harshakasi]

if you print out the device-info [ e.g. model and serial number ] of the two devices you see: are they really the same? As a quick workaround the method CreateFirstDevice() on TlFactory will pick the first on any list

That's exactly what works too, not a workaround but the only way I guess to ensure first of the device objects get used.

[thiesmoeller]

@harshakasi

can you please post the the output of the following script, on the system that shows this issue:

import pypylon.pylon as py

tlf = py.TlFactory.GetInstance()

for tl in tlf.EnumerateTls():
    print(tl.GetDeviceClass(), tl.GetFileName(), tl.GetFullName())

[harshakasi]

@thiesmoeller

Sorry for the delay in my response. Here is the output for the code snippet, Thies:

BaslerUsb N/A USB/BaslerUsb 6.1.2.18349
BaslerUsb N/A USB/BaslerUsb 6.1.2.18349
BaslerGigE N/A GigE/BaslerGigE 6.1.2.18349
BaslerGigE N/A GigE/BaslerGigE 6.1.2.18349

Please advise.

Best,

Harsha

[thiesmoeller]

the copying of the files into the wheel has an issue of accidentally resolving symbolic links. pylon tries to enumerate all transport layers and will find the same library under two names .

mac@macs-MacBook-Pro ~ % sudo dtrace -n 'pid$target:libdyld:dlopen:entry { printf("dlopen: %s\n", copyinstr(arg0));}  ' -c "/Users/mac/.pyenv/versions/3.7.9/bin/python3 test.py"
dtrace: system integrity protection is on, some features will not be available

dtrace: description 'pid$target:libdyld:dlopen:entry ' matched 1 probe
BaslerUsb N/A USB/BaslerUsb 6.1.2.18349
BaslerGigE N/A GigE/BaslerGigE 6.1.2.18349
BaslerGigE N/A GigE/BaslerGigE 6.1.2.18349
dtrace: pid 5883 has exited
CPU     ID                    FUNCTION:NAME
  1   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/_pylon.cpython-37m-darwin.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/liblog4cpp_gcc_v3_1_Basler_pylon.dylib

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/_genicam.cpython-37m-darwin.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/lib-dynload/_heapq.cpython-37m-darwin.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/libpylon_TL_camemu-6.1.2.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/libpylon_TL_camemu.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/libpylon_TL_gige-6.1.2.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/libpylon_TL_gige.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/libpylon_TL_gtc-6.1.2.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/libpylon_TL_gtc.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/libpylon_TL_usb-6.1.2.so

  3   2358                     dlopen:entry dlopen: /Users/mac/.pyenv/versions/3.7.9/lib/python3.7/site-packages/pypylon/pylon.framework/Versions/A/Libraries/pylon-libusb-1.0.dylib

[harshakasi]

Wow! Thanks. So what should be my resolution for this, please? I would like the output for enumeration with just one entry of the connected devices and not duplicates of them.

[kimdonggyun]

Does anybody solve this issue? Still got same issue

[thiesmoeller]

check this ticket also:

https://github.com/basler/pypylon/issues/424#issuecomment-947522532