6by9
commented
8 years ago Sounds like https://github.com/raspberrypi/userland/issues/178 Have you been rebuilding userland with modified build parameters (ie '--no-as-needed')?
Open azasypkin opened 8 years ago
6by9
commented
8 years ago Sounds like https://github.com/raspberrypi/userland/issues/178 Have you been rebuilding userland with modified build parameters (ie '--no-as-needed')?
azasypkin
commented
8 years ago Hey @6by9, thanks for the hint. Currently I use master branch of meta-raspberry and there is --no-as-needed [1] in the userland recipe. With this both raspistill and raspivid work fine, but not picamera python lib. Out of curiosity I was trying to remove --no-as-needed and obviously nothing worked after that :) Or I should try to modify it in some other way?
Also wondering if it's somehow related to the fact that picamera is not included into yocto image from the start and I install it via pip install picamera[array] later on.
waveform80
commented
8 years ago I'm afraid this is all rather beyond my knowledge (I've never dealt with the --as-needed switch or gcc's __attribute__ mechanism), so I doubt I'll be able to shed any light on this. The only thing I would mention is that ctypes in Python (which picamera uses to access libmmal) will be loading the library with dlopen whereas I'd assume raspistill / raspivid will be dynamically linked. I've no idea if/how that could make any difference though.
The manner of picamera's installation shouldn't make any difference; the deb on Raspbian is effectively the result of running pip install, and it certainly won't change the manner in which it accesses libmmal.
cpixl
commented
6 years ago It seems that picamera uses libmmal.so while raspivid and raspistill links against libmmal_{core,util,vc_client}.so directly. On Alpine Linux I added the -DCMAKE_EXE_LINKER_FLAGS='-Wl,--no-as-needed' to cmake (as in the Yocto package) and raspivid/raspistill worked fine but picamera gave exactly the same "Function not implemented" errors (as libmmal still wasn't properly linked to the relevant libs), so I compiled using LDFLAGS="-Wl,--no-as-needed" instead (as in the Void Linux package) and it worked correctly.
ldd /opt/vc/lib/libmmal.so (using -DCMAKE_EXE_LINKER_FLAGS='-Wl,--no-as-needed'):
ldd (0xb6ec1000)
libmmal_core.so => /opt/vc/lib/libmmal_core.so (0xb6e8f000)
libmmal_util.so => /opt/vc/lib/libmmal_util.so (0xb6e71000)
libvcos.so => /opt/vc/lib/libvcos.so (0xb6e58000)
libc.musl-armhf.so.1 => ldd (0xb6ec1000)ldd /opt/vc/lib/libmmal.so (using LDFLAGS="-Wl,--no-as-needed"):
ldd (0xb6eb6000)
libmmal_vc_client.so => /opt/vc/lib/libmmal_vc_client.so (0xb6e87000)
libmmal_components.so => /opt/vc/lib/libmmal_components.so (0xb6e6c000)
libvchiq_arm.so => /opt/vc/lib/libvchiq_arm.so (0xb6e56000)
libvcsm.so => /opt/vc/lib/libvcsm.so (0xb6e40000)
libmmal_core.so => /opt/vc/lib/libmmal_core.so (0xb6e22000)
libmmal_util.so => /opt/vc/lib/libmmal_util.so (0xb6e04000)
libcontainers.so => /opt/vc/lib/libcontainers.so (0xb6de1000)
libvcos.so => /opt/vc/lib/libvcos.so (0xb6dc8000)
libc.musl-armhf.so.1 => ldd (0xb6eb6000)It certainly isn't a bug in picamera, so it seems the only workaround that could be done here would be to use the libmmal_*.so directly as raspivid/raspistill does (idk if that's feasible/possible though).
cpixl
commented
6 years ago NOTE: applying https://github.com/raspberrypi/userland/pull/459 locally still gave me the same results as using -DCMAKE_EXE_LINKER_FLAGS i.e. no libs linked to libmmal.so, so maybe this is relevant to you @6by9 :)
6by9
commented
6 years ago The linker flags are needed when compiling picamera, not libmmal.
https://github.com/raspberrypi/userland/pull/459 only changes the dependencies of the standard apps, not the libraries.
libmmal does NOT depend on libmmal_vc_client. If you wish to use the VPU components then your application needs to link against it, and to NOT over optimise and end up removing the constructor. https://github.com/raspberrypi/userland/issues/178 / https://github.com/raspberrypi/userland/issues/303#issuecomment-204394592
waveform80
commented
6 years ago That's ... odd; picamera isn't compiled (in any meaningful sense). It's just dynamically loading what it needs from the C libs identified in picamera/mmal.py. I'm not entirely familiar with the guts of CPython's ctypes module but I'd guess ultimately it's just calling dlopen and dlsym to grab what it needs from libmmal and libbcm_host. I'm afraid I can't shed much more light on this!
eswarrajan-subrmanian
commented
4 years ago I am also facing a similar error after building userland. I am using the attached python code for livestreaming.
All working fine till this morning, until I built userland for cec-client. Later I am facing this issue everytime. Could someone share me the libmmal_vc_client.so with vc.camera_info included.
Error:
python /home/pimate/ESWAR/LIVE/live.py
mmal: mmal_component_create_core: could not find component 'vc.camera_info'
Traceback (most recent call last):
File "/home/pimate/ESWAR/LIVE/live.py", line 8, in
eswarrajan-subrmanian
commented
4 years ago I am also facing a similar error while building userland. I am using the attached python code for livestreaming.
All working fine till this morning, until I built userland for cec-client. Later I am facing this issue everytime. Could someone share me the libmmal_vc_client.so with vc.camera_info included.
Error: python /home/pimate/ESWAR/LIVE/live.py mmal: mmal_component_create_core: could not find component 'vc.camera_info' Traceback (most recent call last): File "/home/pimate/ESWAR/LIVE/live.py", line 8, in camera = PiCamera() File "/usr/local/lib/python3.6/dist-packages/picamera/camera.py", line 367, in init with mo.MMALCameraInfo() as camera_info: File "/usr/local/lib/python3.6/dist-packages/picamera/mmalobj.py", line 2346, in init super(MMALCameraInfo, self).init() File "/usr/local/lib/python3.6/dist-packages/picamera/mmalobj.py", line 633, in init prefix="Failed to create MMAL component %s" % self.component_type) File "/usr/local/lib/python3.6/dist-packages/picamera/exc.py", line 184, in mmal_check raise PiCameraMMALError(status, prefix) picamera.exc.PiCameraMMALError: Failed to create MMAL component b'vc.camera_info': Function not implemented
Where do i have to put the following to avoid this error? SET( CMAKE_EXE_LINKER_FLAGS "-Wl,--no-as-needed" )
eswarrajan-subrmanian
commented
4 years ago I tried the following and the issue is resolved.
The contents of /opt/vc folder is recreated. This resolves the issue.
mrusme
commented
4 years ago I'm also experiencing this issue with a self-compiled version of the raspberry userland repo on the latest Ubuntu Server image for the Raspberry Pi 4. I've added SET( CMAKE_EXE_LINKER_FLAGS "-Wl,--no-as-needed" ) to the CMakeLists.txt of that repo and ran the buildme script. However, picamera says:
mmal: mmal_component_create_core: could not find component 'vc.camera_info'
Traceback (most recent call last):
File "picam.py", line 171, in <module>
main()
File "picam.py", line 143, in main
with picamera.PiCamera(
File "/usr/local/lib/python3.8/dist-packages/picamera/camera.py", line 367, in __init__
with mo.MMALCameraInfo() as camera_info:
File "/usr/local/lib/python3.8/dist-packages/picamera/mmalobj.py", line 2346, in __init__
super(MMALCameraInfo, self).__init__()
File "/usr/local/lib/python3.8/dist-packages/picamera/mmalobj.py", line 631, in __init__
mmal_check(
File "/usr/local/lib/python3.8/dist-packages/picamera/exc.py", line 184, in mmal_check
raise PiCameraMMALError(status, prefix)
picamera.exc.PiCameraMMALError: Failed to create MMAL component b'vc.camera_info': Function not implementedDoes anyone have another hint here? Thanks!
caiostringari
commented
3 years ago Not a very good fix, but copying libmmal.so from a working version of Raspbian (/opt/vc/lib/libmmal.so) to /usr/lib/arm-linux-gnueabihf/libmmal.so on Ubuntu Mate 20.04 worked for me.
There is a chance that something wrong with the Yocto image itself, but it looks very weird that
raspistill(IIRC it also useslibmmalunder the hood) works andpicameradoesn't. Do you have any idea @waveform80? Thanks!python-pip;Linux raspberrypi2 4.4.23 #1 SMP Tue Oct 4 14:55:18 UTC 2016 armv7l armv7l armv7l GNU/Linux;ldconfig:Everything works fine with
raspistill- no problems whatsoever. But the following code is failing (Python 2.7,picamera 1.12installed viapip install picamera[array]):Here is a verbose python output: