message: dnn: add a check for webcam properties in ssd_mobilenet sample
diff: @@ -115,10 +115,12 @@ int main(int argc, char** argv)
  (inVideoSize.height - cropSize.height) / 2),
  cropSize);
  + double fps = cap.get(CV_CAP_PROP_FPS);
  + int fourcc = static_cast<int>(cap.get(CV_CAP_PROP_FOURCC));
  VideoWriter outputVideo;
  outputVideo.open(parser.get<String>("out") ,
  - static_cast<int>(cap.get(CV_CAP_PROP_FOURCC)),
  - cap.get(CV_CAP_PROP_FPS), cropSize, true);
  + (fourcc != 0 ? fourcc : VideoWriter::fourcc('M','J','P','G')),
  + (fps != 0 ? fps : 10.0), cropSize, true);
  for(;;)
  {
  