[blfs-support] gst-plugins-bad-1.0 does not build if opencv is present

Pierre Labastie pierre.labastie at neuf.fr
Thu Dec 22 07:56:17 PST 2016

On 22/12/2016 16:45, Pierre Labastie wrote:
> On 22/12/2016 16:11, Douglas R. Reno wrote:
>> On Thu, Dec 22, 2016 at 9:06 AM, Pierre Labastie 
>> <pierre.labastie at neuf.fr <mailto:pierre.labastie at neuf.fr>> wrote:
>>     On 22/12/2016 14:59, Douglas R. Reno wrote:
>>>     On Thu, Dec 22, 2016 at 6:58 AM, Pierre Labastie
>>>     <pierre.labastie at neuf.fr <mailto:pierre.labastie at neuf.fr>> wrote:
>>>         Hi,
>>>         I am amazed that nobody came to that earlier, but if
>>>         opencv-3.1.0 is installed as per the book instructions,
>>>         gst-plugins-bad does not build. The error is:
>>>         ------------------------
>>>         make[3]: Entering directory
>>>         '/sources/gst10-plugins-bad/gst-plugins-bad-1.10.2/ext/opencv'
>>>           CXX      libgstopencv_la-gstopencv.lo
>>>         In file included from gstopencv.cpp:41:0:
>>>         gstsegmentation.h:53:32: fatal error: opencv2/bgsegm.hpp: No
>>>         such file or
>>>         directory
>>>            #include <opencv2/bgsegm.hpp>
>>>                                         ^
>>>         compilation terminated.
>>>         make[3]: *** [Makefile:1016: libgstopencv_la-gstopencv.lo]
>>>         Error 1
>>>         -----------------------
>>>         After much research (I'm really not good at finding
>>>         things on internet, thanks Arch linux), I found that
>>>         the bgsegm module is from the opencv_contrib
>>>         package, and not included in the main opencv
>>>         package (there is a cudabgsegm module in the
>>>         main pacakge, but not available if not using cuda,
>>>         that is, nvidia proprietary graphics driver). I have
>>>         not yet tried to build the opencv_contrib package,
>>>         nor to build gst-plugins-bad with that package
>>>         installed. But I wanted to report to see whether
>>>         anybody could confirm. I'd say that if confirmed,
>>>         we should add the opencv_contrib package as
>>>         optional (or disable gstopencv in gst-plugins-bad).
>>>         Regards,
>>>         Pierre
>>>         Regards
>>>     Hi Pierre,
>>>     I generally don't build OpenCV when updating gst-plugins-bad, as
>>>     most of the time I'm heading towards GNOME and need the gst
>>>     plugins as dependencies.
>>>     If you want me to confirm, I'll be building through
>>>     gst-plugins-* in a couple hours, so that I can build WebkitGTK+.
>>>     I can try building OpenCV this time if you want.
>>>     Otherwise, my two cents is to disable gstopencv, but I can see
>>>     where adding the contrib package could help. I just don't see
>>>     too much of a use for OpenCV in gst-plugins-bad currently.
>>     I'd say it would allow to build some image recognition module...
>>     Whether it is useful (for cheese or whatever), I can't tell.
>>     Problem is: opencv is in the in the optional deps of
>>     gst-plugins-bad, so users may build it, for whatever reason [*].
>>     In this case gst-plugins-base does not build. OTOH, BLFS editors
>>     are not supposed to test building with optional deps.
>>     So, I might just disable opencv in gstreamer, and add a command
>>     explanation telling that extra modules are needed if users want
>>     to enable it.
>>     [*] I've bought a webcam, as advised by you ;-), but cheese is
>>     unable to access it, so I thought I would rebuild gst-plugins
>>     with all deps to make sure I have the right ones. The book is not
>>     very explicit about which deps are needed for which usage...
>>     Pierre
>> I'd recommend disabling opencv in gstreamer.
>> I had thought that we were supposed to install all optional 
>> dependencies, and then check our logs to see what the configure 
>> script is checking for.  I always build with optional stuff, but 
>> that's because I almost always have a use for it.
>> You'll need v4l-utils to use the webcam in cheese. I'd recommend 
>> verifying that you have the proper support built in your kernel, and 
>> a driver for the webcam if needed. If you wouldn't mind emailing the 
>> model, I can help if you need it :-)
>> There could also be an issue in Cheese, I won't discount that :-)
> I thought I had built v4l-utils before gst-plugins, but not sure (at 
> the time I did not have the webcam). One thing's sure: I built the 
> needed kernel modules just yesterday. The camera advertises itself as 
> uvc. I have tested it on a debian distro, and it works. The modules in 
> debian (as listed with lsmod), are all now built in my kernel.
> Anyway, rebuilding everything right now (with extra opencv modules). 
> Will let you know whether I have better results.
> At least gst-plugins-bad was built.
It works!
I have to try now with gstopencv disabled (but I have not doubt it will 
still work).
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.linuxfromscratch.org/pipermail/blfs-support/attachments/20161222/7131caa9/attachment.html>

More information about the blfs-support mailing list