“dummy_obj_meta->rect_params.width = ip_surf->surfaceList[frame_meta->batch_id].width;” is wrong. The object is detected and inserted to meta by nvinfer, you can not do it in probe function.
Please refer to Encoding jpeg image after OSD causes segfault - Intelligent Video Analytics / DeepStream SDK - NVIDIA Developer Forums, he does the right thing. deepstream-test5 and deepstream-app are the same.