check pc size

CMakeLists.txt.user

 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE QtCreatorProject>
-<!-- Written by QtCreator 4.11.1, 2023-06-26T18:52:18. -->
+<!-- Written by QtCreator 4.11.1, 2023-06-26T19:12:39. -->
 <qtcreator>
  <data>
   <variable>EnvironmentId</variable>

apps/function/multi_traj_functions.cpp

@@ -436,9 +436,15 @@ vector<CloseTrajInfo> crossFilter(
     pcl::octree::OctreePointCloudSearch<PointExport> octree(resolution);
     octree.setInputCloud(pointClouds.front());
     octree.addPointsFromInputCloud();
-    pcl::io::savePCDFileBinary("/tmp/" + to_string(filteredTaskInfo[0].meshId) + ".pcd", *pointClouds[0]);
+    LOG(INFO) << "pointClouds[" << 0 << "]->size(): " << pointClouds[0]->size();
+    if(pointClouds[0]->size()){
+        pcl::io::savePCDFileBinary("/tmp/" + to_string(filteredTaskInfo[0].meshId) + ".pcd", *pointClouds[0]);
+    }
     for(size_t pcIndex = 1; pcIndex < pointClouds.size(); pcIndex++){
-        pcl::io::savePCDFileBinary("/tmp/" + to_string(filteredTaskInfo[pcIndex].meshId) + ".pcd", *pointClouds[pcIndex]);
+        LOG(INFO) << "pointClouds[" << pcIndex << "]->size(): " << pointClouds[0]->size();
+        if(pointClouds[0]->size()){
+            pcl::io::savePCDFileBinary("/tmp/" + to_string(filteredTaskInfo[pcIndex].meshId) + ".pcd", *pointClouds[pcIndex]);
+        }
         bool found = false;
         bool inPeriod = false;
         uint64_t start = 0, end = 0;