用QT调用OpenCV写了一个带界面的程序，在每次cvReleaseCapture(&capture)后出现如下错误：
(graduation_fix:23510): GLib-GObject-WARNING **: invalid unclassed pointer in cast to 'GstObject'
(graduation_fix:23510): GStreamer-CRITICAL **: gst_object_unref: assertion '((GObject *) object)->ref_count > 0' failed
(graduation_fix:23510): GLib-GObject-WARNING **: invalid unclassed pointer in cast to 'GstObject'
(graduation_fix:23510): GStreamer-CRITICAL **: gst_object_unref: assertion '((GObject *) object)->ref_count > 0' failed
(graduation_fix:23510): GLib-GObject-WARNING **: invalid unclassed pointer in cast to 'GstObject'
(graduation_fix:23510): GStreamer-CRITICAL **: gst_object_unref: assertion '((GObject *) object)->ref_count > 0' failed
(graduation_fix:23510): GStreamer-CRITICAL **: gst_mini_object_unref: assertion 'mini_object->refcount > 0' failed
(graduation_fix:23510): GStreamer-CRITICAL **: gst_mini_object_unref: assertion 'mini_object->refcount > 0' failed
(graduation_fix:23510): GStreamer-CRITICAL **: gst_mini_object_unref: assertion 'mini_object->refcount > 0' failed
capture用来从*.avi文件或camera获取frame：frame=cvQueryFrame(capture);
程序中用了QT的QTimer来定时获取图像
整个程序其他部分没有问题，可以正常退出：
graduation_fix exited with code 0
求大神帮忙分析下！！！！！！！！！！！！