object detection: fix exception

opencv-yolo/web/web.py

@@ -240,6 +240,9 @@ def new_task():
 def video_analysis(data):
     ret = {'code': 0, 'msg': 'ok'}
     ret['target'] = data
+    ret['data'] = {}
+    ret['data']['humanDetect'] = {}
+    ret['data']['humanDetect']['found'] = 0
     print(json.dumps(data))
     imageName = None
     try:
@@ -270,9 +273,6 @@ def video_analysis(data):
             print(cmdLine, '\n\n', cmdArgs)
             output = subprocess.check_output(cmdArgs)
             print(output)
-            ret['data'] = {}
-            ret['data']['humanDetect'] = {}
-            ret['data']['humanDetect']['found'] = 0
             # parse
             for line in output.decode('utf-8').split('\n'):
                 print("\n", line)