Allow developers (or advanced users) to override UI settings - quite useful if...

Allow developers (or advanced users) to override UI settings - quite useful if you set your debug settings in QtCreator and do not depends on QGC settings state (they are reset to default sometimes, for example)

src/VideoStreaming/VideoStreaming.cc

@@ -132,7 +132,7 @@ void initializeVideoStreaming(int &argc, char* argv[], char* logpath, char* debu
         gst_ios_init();
     #else
         //-- Generic initialization
-        if (logpath) {
+        if (qgetenv("GST_DEBUG").isEmpty() && logpath) {
             QString gstDebugFile = QString("%1/%2").arg(logpath).arg("gstreamer-log.txt");
             qDebug() << "GStreamer debug output:" << gstDebugFile;
             if (debuglevel) {