Compiler error in pmsis_tools_frame_streamer.cpp

[jonasdn]

python/pmsis_tools_frame_streamer.cpp: In member function ‘virtual void Frame_stream::handle_req(Transport_req_t*)’:
python/pmsis_tools_frame_streamer.cpp:264:41: error: ‘CV_LOAD_IMAGE_GRAYSCALE’ was not declared in this scope
  264 |       Mat image = imdecode(input_array, CV_LOAD_IMAGE_GRAYSCALE);
      |                                         ^~~~~~~~~~~~~~~~~~~~~~~
python/pmsis_tools_frame_streamer.cpp: In function ‘void* frame_stream_get_frame(void*, unsigned char*)’:
python/pmsis_tools_frame_streamer.cpp:364:1: warning: no return statement in function returning non-void [-Wreturn-type]
  364 | }
      | ^