Continue loop if frame Mat is empty

opencv_fb.cpp

@@ -74,7 +74,7 @@ void display (Mat frame, framebuffer_info fb_info, ofstream& ofs) {
                     }
                 } break;
             default:
-                cerr << "Unsupported depth of framebuffer." << endl;
+                cerr << "Unsupported depth of framebuffer: " << framebuffer_depth << endl;
         }
     }
 }
@@ -111,6 +111,9 @@ int main(int, char**) {
         Mat displayFrame;
         while (true) {
             cap >> frame;
+            if (frame.empty()) {
+                continue;
+            }
             frame = frameEffects(frame);
             resize(frame, displayFrame, Size(fb_info.xres_virtual, fb_info.yres_virtual), 2, 2, INTER_CUBIC);
             display(displayFrame, fb_info, ofs);