I am a beginner at OpenCV and trying my best to get a simple application running on an embedded platform. I cross-compiled OpenCV 2.4.4 and built it WITH_GTK=ON, WITH_UNICAP=ON, WITH_V4L=ON as needed for camera and GUI support. The following sample code cross-compiles on host:

#include <opencv/cv.h>
#include <opencv/highgui.h>
using namespace cv; 
int main(int, char**)
{
    VideoCapture cap(0); // open the default camera
    if (!cap.isOpened()) // check if we succeeded
        return -1;

    Mat edges;
    namedWindow("edges", 1);
    for (;;) {
        Mat frame;
        cap >> frame;   // get a new frame from camera
        cvtColor(frame, edges, CV_BGR2GRAY);
        GaussianBlur(edges, edges, Size(7, 7), 1.5, 1.5);
        Canny(edges, edges, 0, 30, 3);
        imshow("edges", edges);
        if (waitKey(30) >= 0)
            break;
    }
    return 0;
}

Compiling this way for static linking:

arm-linux-gnueabi-g++ -mcpu=cortex-a9 -mfpu=neon -static opencv_camshow.cpp -o exe -I/home/om/OpenCV-2.4.4/platforms/linux/build_soft/install/include -L/home/om/OpenCV-2.4.4/platforms/linux/build_soft/install/lib -L/home/om/OpenCV-2.4.4/platforms/linux/build_soft/3rdparty/lib -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_imgproc -lopencv_core -lopencv_contrib -lopencv_highgui -lopencv_ml -lopencv_video -lopencv_flann -lopencv_photo -lopencv_videostab -pthread -lm -lrt -lzlib -static

Here is the problem. When I try to run the executable file 'exe' on the target, I get this runtime error:

HIGHGUI ERROR: V4L/V4L2: VIDIOC_S_CROP OpenCV Error: Unspecified error (The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Carbon support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script) in cvNamedWindow, file /home/om/OpenCV-2.4.4/module

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