Thread 29 "dms_qt" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fff31c24700 (LWP 17553)]
0x00007fffea4548c1 in cv::CvtColorLoop_Invoker<cv::RGB2Gray<unsigned char> >::operator()(cv::Range const&) const () from /usr/local/lib/libopencv_imgproc.so.3.4
(gdb) bt
#0  0x00007fffea4548c1 in cv::CvtColorLoop_Invoker<cv::RGB2Gray<unsigned char> >::operator()(cv::Range const&) const () at /usr/local/lib/libopencv_imgproc.so.3.4
#1  0x00007fffe922bfc5 in (anonymous namespace)::ParallelLoopBodyWrapper::operator()(cv::Range const&) const () at /usr/local/lib/libopencv_core.so.3.4
#2  0x00007fffe922c99a in cv::ParallelJob::execute(bool) () at /usr/local/lib/libopencv_core.so.3.4
#3  0x00007fffe922d415 in cv::WorkerThread::thread_body() () at /usr/local/lib/libopencv_core.so.3.4
#4  0x00007fffe922d4e9 in cv::WorkerThread::thread_loop_wrapper(void*) () at /usr/local/lib/libopencv_core.so.3.4
#5  0x00007fffeec006db in start_thread (arg=0x7fff31c24700) at pthread_create.c:463
#6  0x00007fffe830788f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
(gdb)