c++ - Show camera image with Qt gives HIGHGUI ERROR: V4L/V4L2: VIDIOC_S_CROP -

i trying see camera on qlabel, cannot see opencv window. after start application there small window created opencv there no image. , in log can see errors:

highgui error: v4l/v4l2: vidioc_s_crop  (<unknown>:7534): gtk-warning **: gtk_disable_setlocale() must called before gtk_init() in capture...  corrupt jpeg data: 1 extraneous bytes before marker 0xd9 corrupt jpeg data: 1 extraneous bytes before marker 0xd9 corrupt jpeg data: 1 extraneous bytes before marker 0xd9 

here simple code :

void mainwindow::on_pushbutton_clicked() {     cvcapture* capture = 0;     cv::mat frame, framecopy;      capture = cvcapturefromcam(cv_cap_any); //0=default, -1=any camera, 1..99=your camera     if(!capture)     {         qdebug() << "no camera detected";     }         if( capture )     {         qdebug() << "in capture...";          for(;;)         {             iplimage* iplimg = cvqueryframe( capture );             frame = iplimg;             if( frame.empty() )                 break;             if( iplimg->origin == ipl_origin_tl )                 frame.copyto( framecopy );             else                 flip( frame, framecopy, 0 );              if( cv::waitkey( 10 ) >= 0 )                 break;             cv::imshow("result", framecopy);         }     }     //    cv::waitkey(0);      cvreleasecapture(&capture);     cvdestroywindow("result");  } 

could please give me idea, why highgui error , how solve it?

you getting corrupted data camera. jpeg decoder can not decode it. can try increase duration of cvwaitkey().

i hope works you.