Segfault when using CvSource

[DrWateryCat]

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I am trying to use cscore to stream a kinect's RGB and depth data over a MJPEG connection, but when I call PutFrame, I get a segfault. Here's a gist of the C++ code I'm using: https://gist.github.com/DrWateryCat/c225e436d5761bbb21fd622c78e78972 and here's the stacktrace by valgrind:

==25030== Use of uninitialised value of size 8
==25030==    at 0x5AA09F5: cv::Mat::copyTo(cv::_OutputArray const&) const (in /usr/lib/x86_64-linux-gnu/libopencv_core.so.2.4.9)
==25030==    by 0x5EFAF60: cs::CvSourceImpl::PutFrame(cv::Mat&) (in /usr/local/lib/libcscore.so)
==25030==    by 0x5EFC460: cs::PutSourceFrame(int, cv::Mat&, int*) (in /usr/local/lib/libcscore.so)
==25030==    by 0x40685E: cs::CvSource::PutFrame(cv::Mat&) (cscore_oo.inl:343)
==25030==    by 0x404393: main (libfreenect_opencvtest.cpp:328)
==25030== 
==25030== Invalid read of size 8
==25030==    at 0x5AA09F5: cv::Mat::copyTo(cv::_OutputArray const&) const (in /usr/lib/x86_64-linux-gnu/libopencv_core.so.2.4.9)
==25030==    by 0x5EFAF60: cs::CvSourceImpl::PutFrame(cv::Mat&) (in /usr/local/lib/libcscore.so)
==25030==    by 0x5EFC460: cs::PutSourceFrame(int, cv::Mat&, int*) (in /usr/local/lib/libcscore.so)
==25030==    by 0x40685E: cs::CvSource::PutFrame(cv::Mat&) (cscore_oo.inl:343)
==25030==    by 0x404393: main (libfreenect_opencvtest.cpp:328)
==25030==  Address 0xfc2010040 is not stack'd, malloc'd or (recently) free'd
==25030== 
==25030== 
==25030== Process terminating with default action of signal 11 (SIGSEGV)
==25030==  Access not within mapped region at address 0xFC2010040
==25030==    at 0x5AA09F5: cv::Mat::copyTo(cv::_OutputArray const&) const (in /usr/lib/x86_64-linux-gnu/libopencv_core.so.2.4.9)
==25030==    by 0x5EFAF60: cs::CvSourceImpl::PutFrame(cv::Mat&) (in /usr/local/lib/libcscore.so)
==25030==    by 0x5EFC460: cs::PutSourceFrame(int, cv::Mat&, int*) (in /usr/local/lib/libcscore.so)
==25030==    by 0x40685E: cs::CvSource::PutFrame(cv::Mat&) (cscore_oo.inl:343)
==25030==    by 0x404393: main (libfreenect_opencvtest.cpp:328)
==25030==  If you believe this happened as a result of a stack
==25030==  overflow in your program's main thread (unlikely but
==25030==  possible), you can try to increase the size of the
==25030==  main thread stack using the --main-stacksize= flag.
==25030==  The main thread stack size used in this run was 8388608.

[virtuald]

It appears that if kinect.GetVideo() returns false, the Mat won't be initialized, which would lead to this bug.

[virtuald]

And by "this bug", I mean it's a bug in your program, not cscore. :)

[DrWateryCat]

I added if (!kinect.GetVideo(rgb)) { rgb = cv::Mat::zeros(cv::Size(640, 480), CV_8UC3); }just inside the while loop, and took out the PutFrame for the depth data. Valgrind gives the same error.