@JonB said in What should I do to solve this error in Qvector?:

if you are saying that a properly-compiled 64-bit now bombs out in the same way as 32-bit at what we think is only half a gig of so of memory on a machine with plenty of free RAM,

earlier I was doing mistake while creating 64 bit application version. I am using visual studio while creating 64 bit application I was just copied all setting of 32 bit application, So That in Solution platform it was showing x64 but it was creating 32 bit executable file.

I created 64 bit application version, which is save very large amount of data in RAM.

@chris1092387456 could it be possible you have mixed Qt versions from the one you cross-compiled and the one it's used by the OpenCV install script you used.

Assuming you run Ubuntu/opencv_latest.sh which in turn calls opencv_install.sh and then dependencies.sh, there are some apt-get install calls, so you''ll end up having pre-built Qt libraries along with your cross-compiled ones...

function install_dependency { echo "--- Installing dependency: $1" sudo apt-get -y install $1 } ... install_dependency libqt5x11extras5 install_dependency libqt5opengl5 install_dependency libqt5opengl5-dev

So may I suggest to start from scratch?

First I'd follow the mechatronics guide to cross-compile and deploy Qt in the RPi device.

Then I'd follow this guide to cross compile the latest version of OpenCV for Raspberry Pi. As you'll use WITH_QT=ON flag I guess, please adjust the paths in the CMake script(s) to use the cross-compiled Qt version in your host PC.

And also use the correct path for cross-compiled OpenCV in your .pro file. As example, the following doesn't look good to me:

LIBS += -L/usr/local/lib/libopencv_highgui.so