Hi
Is there any update for when the python bindings for the Gst-nvdsanalytics meta data will be available?
Best,
Niels
It should work on 5.0GA, refer Deepstream Python API Reference â Deepstream Deepstream Version: 6.1.1 documentation
But how do I access the analytics meta data generated from the Gst-nvdsanalytics component? In the C++ example (deepstream-nvdsanalytics-test) they access it from the NvDsUserMeta attached to the NvDsObjectMeta:
for (l_obj = frame_meta->obj_meta_list; l_obj != NULL;
l_obj = l_obj->next) {
obj_meta = (NvDsObjectMeta *) (l_obj->data);
// Access attached user meta for each object
for (NvDsMetaList *l_user_meta = obj_meta->obj_user_meta_list; l_user_meta != NULL;
l_user_meta = l_user_meta->next) {
NvDsUserMeta *user_meta = (NvDsUserMeta *) (l_user_meta->data);
if(user_meta->base_meta.meta_type == NVDS_USER_OBJ_META_NVDSANALYTICS)
{
NvDsAnalyticsObjInfo * user_meta_data =
(NvDsAnalyticsObjInfo *)user_meta->user_meta_data;
if (user_meta_data->dirStatus.length()){
out_string << " object " << obj_meta->object_id <<
" is moving in " << user_meta_data->dirStatus;
}
}
}
}
I am able to iterate the user meta data in python and it contains something but I cant seem to figure out how to cast it to the NvDsAnalyticsObjInfo object such that I can access the data from python. I have tried the following in my python probe:
user_meta_list = obj_meta.obj_user_meta_list
while user_meta_list is not None:
user_meta = pyds.NvDsUserMeta.cast(user_meta_list.data)
user_meta_data = user_meta.user_meta_data
try:
user_meta_list=user_meta_list.next
except StopIteration:
break
+1 Would also like to see an examle
Currently, the python bindings donât have a âcastâ function for NvDsAnalyticsObjInfo, but you can generate your bindings and cast function as follows
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
#include "nvds_analytics_meta.h"
namespace py = pybind11;
PYBIND11_MODULE(pyds_analytics, m) {
py::class_<NvDsAnalyticsObjInfo>(m,"NvDsAnalyticsObjInfo")
.def(py::init<>())
.def_readwrite("roiStatus",&NvDsAnalyticsObjInfo::roiStatus)
.def_readwrite("ocStatus",&NvDsAnalyticsObjInfo::ocStatus)
.def_readwrite("lcStatus",&NvDsAnalyticsObjInfo::lcStatus)
.def_readwrite("dirStatus",&NvDsAnalyticsObjInfo::dirStatus)
.def_readwrite("unique_id",&NvDsAnalyticsObjInfo::unique_id)
.def(âcastâ,[](void *data){
return (NvDsAnalyticsObjInfo*)data;
});
py::class_<NvDsAnalyticsFrameMeta>(m,"NvDsAnalyticsFrameMeta)
.def(py::init<>())
.def_readwrite("ocStatus",&NvDsAnalyticsFrameMeta::ocStatus)
.def_readwrite("objInROIcnt",&NvDsAnalyticsFrameMeta::objInROIcnt)
.def_readwrite("objLCCurrCnt",&NvDsAnalyticsFrameMeta::objLCCurrCnt)
.def_readwrite("objLCCumCnt",&NvDsAnalyticsFrameMeta::objLCCumCnt)
.def_readwrite("unique_id",&NvDsAnalyticsFrameMeta::unique_id)
.def_readwrite("objCnt",&NvDsAnalyticsFrameMeta::objCnt)
.def(âcastâ,[](void *data){
return (NvDsAnalyticsFrameMeta *)data;
});
}Save this file as pyds_analytics.cpp and then to generate bindings please refer to the following repo GitHub - mrtj/pyds_tracker_meta: pybind11 wrapper to access Nvidia DeepStream tracker meta info from Python.
Replace the pyds_tracker_meta.cpp with pyds_analytics.cpp and do the same in build.sh and setup.py files, to generate the bindings. Then you can cast the user_meta.user_meta_data to NvDsAnalyticsObjInfo as follows
import pyds_analytics
ObjInfo=pyds_analytics.NvDsAnalyticsObjInfo.cast(user_meta.user_meta_data)
2 Likes
Ahh perfect! Thanks for the detailed answer. I will make sure to test it as soon as possible.
@manojy Thanks for the workaround info, successfully built and install so file import also working, but import in deepstream app is giving this error
Traceback (most recent call last):
File "temp.py", line 44, in <module>
import pyds
ImportError: generic_type: type "NvDsAnalyticsObjInfo" is already registered!
Referring to Classes - pybind11 documentation added this py::module_local() now able to import in deepstream app but ObjInfo=pyds_analytics.NvDsAnalyticsObjInfo.cast(user_meta.user_meta_data) this causes Segmentation fault (core dumped) and exits
pyds_analytics.cpp
include <pybind11/pybind11.h>
include <pybind11/stl.h>
include ânvds_analytics_meta.hânamespace py = pybind11;
PYBIND11_MODULE(pyds_analytics, m) {
py::class_(m,âNvDsAnalyticsObjInfoâ, py::module_local())
.def(py::init<>())
.def_readwrite(âroiStatusâ,&NvDsAnalyticsObjInfo::roiStatus)
.def_readwrite(âocStatusâ,&NvDsAnalyticsObjInfo::ocStatus)
.def_readwrite(âlcStatusâ,&NvDsAnalyticsObjInfo::lcStatus)
.def_readwrite(âdirStatusâ,&NvDsAnalyticsObjInfo::dirStatus)
.def_readwrite(âunique_idâ,&NvDsAnalyticsObjInfo::unique_id)
.def(âcastâ,(void data){
return (NvDsAnalyticsObjInfo)data;
});
py::class_(m,âNvDsAnalyticsFrameMetaâ, py::module_local())
.def(py::init<>())
.def_readwrite(âocStatusâ,&NvDsAnalyticsFrameMeta::ocStatus)
.def_readwrite(âobjInROIcntâ,&NvDsAnalyticsFrameMeta::objInROIcnt)
.def_readwrite(âobjLCCurrCntâ,&NvDsAnalyticsFrameMeta::objLCCurrCnt)
.def_readwrite(âobjLCCumCntâ,&NvDsAnalyticsFrameMeta::objLCCumCnt)
.def_readwrite(âunique_idâ,&NvDsAnalyticsFrameMeta::unique_id)
.def_readwrite(âobjCntâ,&NvDsAnalyticsFrameMeta::objCnt)
.def(âcastâ,(void *data){
return (NvDsAnalyticsFrameMeta *)data;
});
}
App Function
def nvdsanalytics_src_pad_buffer_probe(pad,info,u_data):
gst_buffer = info.get_buffer() if not gst_buffer: print("Unable to get GstBuffer ") return batch_meta = pyds.gst_buffer_get_nvds_batch_meta(hash(gst_buffer)) l_frame = batch_meta.frame_meta_list while l_frame is not None: try: frame_meta = pyds.NvDsFrameMeta.cast(l_frame.data) except StopIteration: break l_user = frame_meta.frame_user_meta_list while l_user is not None: try: user_meta = pyds.NvDsUserMeta.cast(l_user.data) ObjInfo=pyds_analytics.NvDsAnalyticsObjInfo.cast(user_meta.user_meta_data) except StopIteration: break try: l_user=l_user.next except sStopIteration: break try: l_frame=l_frame.next except StopIteration: break return Gst.PadProbeReturn.OK
Can you check your code snippet format, forum support markdown syntax
1 Like
As NvDsAnalyticsObjInfo struct has already binded in pyds, you can simply add the following casting function to get NvDsAnalyticsObjInfo.
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
#include "nvds_analytics_meta.h"
namespace py = pybind11;
PYBIND11_MODULE(pyds_analytics, m) {
m.def("cast_to_NvDsAnalyticsObjInfo",[](void *data){
return (NvDsAnalyticsObjInfo*)data;
});
}@manojy Now really confused what to use and how to use, could you acknowledge what is wrong in above code snippets.
@bcao didnât get you
Hello
the link to the pyds_tracker_meta bindings worked great
As for pyds_analytics_meta, I am having far more trouble.
Ive had to comment out the line
// .def_readwrite(âobjCntâ,&NvDsAnalyticsFrameMeta::objCnt)
============= pyds_analytics_meta.cpp ===============
#include <pybind11/pybind11.h> #include <pybind11/stl.h> #include "nvds_analytics_meta.h" namespace py = pybind11; PYBIND11_MODULE(pyds_tracker_meta, m) { m.doc() = "pybind11 wrapper to access Nvidia DeepStream NvDsAnalyticsMeta* classes"; // m.def("cast_to_NvDsAnalyticsObjInfo"[](void *data){ // return (NvDsAnalyticsObjInfo*)data; // }); py::class_<NvDsAnalyticsObjInfo>(m,"NvDsAnalyticsObjInfo", py::module_local()) // py::class_(m,âNvDsAnalyticsObjInfoâ, py::module_local()) .def(py::init<>()) .def_readwrite("roiStatus",&NvDsAnalyticsObjInfo::roiStatus) .def_readwrite("ocStatus",&NvDsAnalyticsObjInfo::ocStatus) .def_readwrite("lcStatus",&NvDsAnalyticsObjInfo::lcStatus) .def_readwrite("dirStatus",&NvDsAnalyticsObjInfo::dirStatus) .def_readwrite("unique_id",&NvDsAnalyticsObjInfo::unique_id) .def("cast",[](void *data){ return (NvDsAnalyticsObjInfo*)data; }); py::class_<NvDsAnalyticsFrameMeta>(m,"NvDsAnalyticsFrameMeta", py::module_local()) .def(py::init<>()) .def_readwrite("ocStatus",&NvDsAnalyticsFrameMeta::ocStatus) .def_readwrite("objInROIcnt",&NvDsAnalyticsFrameMeta::objInROIcnt) .def_readwrite("objLCCurrCnt",&NvDsAnalyticsFrameMeta::objLCCurrCnt) .def_readwrite("objLCCumCnt",&NvDsAnalyticsFrameMeta::objLCCumCnt) .def_readwrite("unique_id",&NvDsAnalyticsFrameMeta::unique_id) // .def_readwrite("objCnt",&NvDsAnalyticsFrameMeta::objCnt) <------- needed to be uncommented .def("cast",[](void *data){ return (NvDsAnalyticsFrameMeta *)data; }); }
============= nvds_analytics_meta.cpp ===============
/** * Copyright (c) 2020, NVIDIA CORPORATION. All rights reserved. * * NVIDIA Corporation and its licensors retain all intellectual property * and proprietary rights in and to this software, related documentation * and any modifications thereto. Any use, reproduction, disclosure or * distribution of this software and related documentation without an express * license agreement from NVIDIA Corporation is strictly prohibited. * */ #ifndef _NVDS_ANALYTICS_META_H_ #define _NVDS_ANALYTICS_META_H_ #include <gst/gst.h> #ifdef __cplusplus extern "C" { #endif #define NVDS_USER_FRAME_META_NVDSANALYTICS (nvds_get_user_meta_type((gchar*)"NVIDIA.DSANALYTICSFRAME.USER_META")) #define NVDS_USER_OBJ_META_NVDSANALYTICS (nvds_get_user_meta_type((gchar*)"NVIDIA.DSANALYTICSOBJ.USER_META")) /** */ typedef struct { std::vector <std::string> roiStatus; std::vector <std::string> ocStatus; std::vector <std::string> lcStatus; std::string dirStatus; guint unique_id; } NvDsAnalyticsObjInfo; /** */ typedef struct { std::unordered_map<std::string, bool> ocStatus; std::unordered_map<std::string, uint32_t> objInROIcnt; std::unordered_map<std::string, uint64_t> objLCCurrCnt; std::unordered_map<std::string, uint64_t> objLCCumCnt; guint unique_id; } NvDsAnalyticsFrameMeta; #ifdef __cplusplus } #endif #endif
when I check the header file for the class it is indeed missing object count? Could this mean i am using a more out of date deepstream (5.0 jetpack 4.4)
However I can build and install it when objCnt is removed, but I cannot import the class into my deepstream application, or even an empty project, it throws the following error
import pyds_analytics_meta
Traceback (most recent call last):
File ââ, line 1, in
ImportError: dynamic module does not define module export function (PyInit_pyds_analytics_meta)
Any help would be greatly appreciated
Regards Andrew
I have fixed some of my issues
Firstly i cleared some space on hdd and managed to update via the software updater (I noticed there were deepstream updates, now nvds_analytics_meta.cpp has objCnt.
I also realised "PYBIND11_MODULE(pyds_tracker_meta, m) " should have been PYBIND11_MODULE(pyds_tracker, m)
Now it successfully imports and i can use:
user_meta_analytics = pyds_analytics.NvDsAnalyticsObjInfo.cast(user_meta.user_meta_data)
however the pipeline freezes and causes Segmentation fault (core dumped) Same as @priyanshthakore
@manojy please clarify this
note missing " , " after cast_to_NvDsAnalyticsObjInfo
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
#include "nvds_analytics_meta.h"
namespace py = pybind11;
PYBIND11_MODULE(pyds_analytics, m) {
m.def("cast_to_NvDsAnalyticsObjInfo",[](void *data){
return (NvDsAnalyticsObjInfo*)data;
});
}
then to access the NvDsAnalyticsObjInfo:
l_user = frame_meta.frame_user_meta_list
while l_user is not None:
try:
print('try cast')
user_meta = pyds.NvDsUserMeta.cast(l_user.data)
if user_meta.user_meta_data:
try:
print('user meta', user_meta.user_meta_data)
user_meta_analytics = pyds_analytics.cast_to_NvDsAnalyticsObjInfo(user_meta.user_meta_data)
# user_meta_analytics = pyds_analytics.NvDsAnalyticsObjInfo.cast(user_meta.user_meta_data)
print('user_meta_analytics:', user_meta_analytics)
except Exception as ex:
print('exception', ex)
print('user_meta', user_meta)
except StopIteration:
break
try:
l_user = l_user.next
except StopIteration:
break
print('=======================================================================================')
or
user_meta_list = batch_meta.batch_user_meta_list
while user_meta_list is not None:
user_meta = pyds.NvDsUserMeta.cast(user_meta_list.data)
if user_meta.user_meta_data:
try:
print('user meta',user_meta.user_meta_data)
user_meta_analytics = pyds_analytics.cast_to_NvDsAnalyticsObjInfo(user_meta.user_meta_data)
# user_meta_analytics = pyds_analytics.NvDsAnalyticsObjInfo.cast(user_meta.user_meta_data)
print('user_meta_analytics:', user_meta_analytics)
except Exception as ex:
print('exception',ex)
Yields the following exception
exception Unable to convert function return value to a Python type! The signature was
(arg0: capsule) â NvDsAnalyticsObjInfo
I am seen the same as @priyanshthakore and @Andrew_Smith.
I did the following as suggested by @manojy and added the py::module_local() (ref @priyanshthakore) :
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
#include "nvds_analytics_meta.h"
namespace py = pybind11;
PYBIND11_MODULE(pyds_analytics, m) {
py::class_<NvDsAnalyticsObjInfo>(m,"NvDsAnalyticsObjInfo",py::module_local())
.def(py::init<>())
.def_readwrite("roiStatus",&NvDsAnalyticsObjInfo::roiStatus)
.def_readwrite("ocStatus",&NvDsAnalyticsObjInfo::ocStatus)
.def_readwrite("lcStatus",&NvDsAnalyticsObjInfo::lcStatus)
.def_readwrite("dirStatus",&NvDsAnalyticsObjInfo::dirStatus)
.def_readwrite("unique_id",&NvDsAnalyticsObjInfo::unique_id)
.def("cast",[](void *data){
return (NvDsAnalyticsObjInfo*)data;
});
py::class_<NvDsAnalyticsFrameMeta>(m,"NvDsAnalyticsFrameMeta",py::module_local())
.def(py::init<>())
.def_readwrite("ocStatus",&NvDsAnalyticsFrameMeta::ocStatus)
.def_readwrite("objInROIcnt",&NvDsAnalyticsFrameMeta::objInROIcnt)
.def_readwrite("objLCCurrCnt",&NvDsAnalyticsFrameMeta::objLCCurrCnt)
.def_readwrite("objLCCumCnt",&NvDsAnalyticsFrameMeta::objLCCumCnt)
.def_readwrite("unique_id",&NvDsAnalyticsFrameMeta::unique_id)
.def_readwrite("objCnt",&NvDsAnalyticsFrameMeta::objCnt)
.def("cast",[](void *data){
return (NvDsAnalyticsFrameMeta *)data;
});
}
And accessing the NvDsAnalyticsObjInfo in python through:
user_meta_list = obj_meta.obj_user_meta_list
print(user_meta_list)
while user_meta_list is not None:
user_meta = pyds.NvDsUserMeta.cast(user_meta_list)
print(user_meta)
try:
analytic_obj = pyds_analytics.NvDsAnalyticsObjInfo.cast(user_meta.user_meta_data)
if analytic_obj is not None:
print(analytic_obj)
try:
user_meta_list=user_meta_list.next
except StopIteration:
break
I also did as suggested by @manojy and tried with:
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
#include "nvds_analytics_meta.h"
namespace py = pybind11;
PYBIND11_MODULE(pyds_analytics, m) {
m.def("cast_to_NvDsAnalyticsObjInfo",[](void *data){
return (NvDsAnalyticsObjInfo *)data;
});
m.def("cast_to_NvDsAnalyticsFrameMeta",[](void *data){
return (NvDsAnalyticsFrameMeta *)data;
});
}
And again accessing the NvDsAnalyticsObjInfo in python through:
user_meta_list = obj_meta.obj_user_meta_list
print(user_meta_list)
while user_meta_list is not None:
user_meta = pyds.NvDsUserMeta.cast(user_meta_list)
print(user_meta)
try:
analytic_obj = pyds_analytics.cast_to_NvDsAnalyticsObjInfo(user_meta.user_meta_data)
if analytic_obj is not None:
print(analytic_obj)
try:
user_meta_list=user_meta_list.next
except StopIteration:
break
The result is the same for both approaches and my terminal output looks like this when it freezes and stops:
user meta (obj) list <pyds.GList object at 0x7f505f29d0>
<pyds.NvDsUserMeta object at 0x7f505f2a40>
<pyds_analytics.NvDsAnalyticsObjInfo object at 0x7f505f2a08>
Segmentation fault (core dumped)
The problem is occurring due to the py::return_value_policy::automatic_reference, which is default pybind11 reference, this is causing memory dealloc problem which is resulting in segmentation fault. So changing it to py::return_value_policy::reference will work. Please use the following solution.
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
#include "nvds_analytics_meta.h"
namespace py = pybind11;
PYBIND11_MODULE(pyds_analytics, m) {
py::class_<NvDsAnalyticsObjInfo>(m,"NvDsAnalyticsObjInfo",py::module_local())
.def(py::init<>())
.def_readwrite("roiStatus",&NvDsAnalyticsObjInfo::roiStatus)
.def_readwrite("ocStatus",&NvDsAnalyticsObjInfo::ocStatus)
.def_readwrite("lcStatus",&NvDsAnalyticsObjInfo::lcStatus)
.def_readwrite("dirStatus",&NvDsAnalyticsObjInfo::dirStatus)
.def_readwrite("unique_id",&NvDsAnalyticsObjInfo::unique_id)
.def_static("cast",[](void *data){
return (NvDsAnalyticsObjInfo*)data;
},py::return_value_policy::reference);
py::class_<NvDsAnalyticsFrameMeta>(m,"NvDsAnalyticsFrameMeta",py::module_local())
.def(py::init<>())
.def_readwrite("ocStatus",&NvDsAnalyticsFrameMeta::ocStatus)
.def_readwrite("objInROIcnt",&NvDsAnalyticsFrameMeta::objInROIcnt)
.def_readwrite("objLCCurrCnt",&NvDsAnalyticsFrameMeta::objLCCurrCnt)
.def_readwrite("objLCCumCnt",&NvDsAnalyticsFrameMeta::objLCCumCnt)
.def_readwrite("unique_id",&NvDsAnalyticsFrameMeta::unique_id)
.def_readwrite("objCnt",&NvDsAnalyticsFrameMeta::objCnt)
.def_static("cast",[](void *data){
return (NvDsAnalyticsFrameMeta *)data;
},py::return_value_policy::reference);
}
1 Like
@manojy - I just tried the fix and I am still seeing a segmentation fault (core dumped). Have you tried the code yourself and if so do you have a complete working example?
Secondly, is it possible to get and see the actual python deepstream bindings (pyds)? I can only find the compiled .so (pyds.so) in the deepstream SDK.
I tried the fix and it works, no segmentation fault
however I am still attempting to access the data
user_meta_list = batch_meta.batch_user_meta_list
print(â======================================================================================â)while user_meta_list is not None: user_meta = pyds.NvDsUserMeta.cast(user_meta_list.data) if user_meta.user_meta_data: try: print('user meta',user_meta.user_meta_data) # user_meta_analytics = pyds_analytics.cast_to_NvDsAnalyticsObjInfo(user_meta.user_meta_data) user_meta_analytics = pyds_analytics.NvDsAnalyticsObjInfo.cast(user_meta.user_meta_data) print('user_meta_analytics:', user_meta_analytics) ============== Breaks here ============== print('dirStatus',user_meta_analytics.dirStatus) print('lcStatus',user_meta_analytics.lcStatus) print('ocStatus',user_meta_analytics.ocStatus) print('roiStatus',user_meta_analytics.roiStatus) except Exception as ex: print('exception',ex) try: user_meta_list = user_meta_list.next except StopIteration: break print('======================================================================================')
True, I am also able to do the cast but it fails when I access the data fields just as you