VPI Python Import Error

[yasinbedirhansimseq]

Hi everyone,

I am currently trying to get the stereo disparity estimator in the VPI to work with Python but there is a problem with the import section. No module error is thrown. When currently installed modules are checked, VPI is not on the list.

import vpi

Gives “no module named vpi” error. I can’t import VPI using Python 3.7.1. Python 2.7 also gives the same error.

However, i think the VPI 1.1 is installed on the system because when I check with

apt show cache nvidia-vpi

The log result is below

#################################

Package: nvidia-vpi

Version: 4.5.1-b17

Priority: standard

Section: metapackages

Maintainer: NVIDIA Corporation

Installed-Size: 199 kB

Depends: libnvvpi1 (= 1.0.15), vpi1-dev (= 1.0.15), vpi1-samples (= 1.0.15), vpi1-demos (= 1.0.15)

Homepage: http://developer.nvidia.com/jetson

Download-Size: 29,3 kB

APT-Manual-Installed: yes

APT-Sources: https://repo.download.nvidia.com/jetson/t210 r32.5/main arm64 Packages

Description: NVIDIA Vpi Meta Package

N: Unable to locate package cache

N: Unable to locate package cache

N: There is 1 additional record. Please use the '-a' switch to see it

I can also run the VPI Remap demo with the “VPI Demos V1.0” on the desktop. It opens a folder with a single demo in it. It is the “VPI Remap Demo 1.0”. When I run it, it connects to my camera and 4 video streams with different transformations (mirror, pinch, whirl, waves) run simultaneously on CUDA.

Jetson Nano 4GB
Ubuntu 18.04.6 LTS

Any help would be appreciated, Thanks

[AastaLLL]

Hi,

Please noted that VPI is compiled with the default python version, which should be version 3.6.
Would you mind importing it with python 3.6 to see if it works?

Thanks.

[yasinbedirhansimseq]

Hi, thank you for answering. I currently have multiple python installations on my system. One of them is Python 3.6.9.

I don’t know if it should be exactly Python 3.6.0 but it again gave “no module named vpi” error.

Code i tried:

import sys

print(sys.version)

import vpi

Output:

3.6.9 (default, Jan 26 2021, 15:33:00) 
[GCC 8.4.0]
Traceback (most recent call last):
  File "/home/cezeri/Gimbal/VPI_import_test.py", line 5, in <module>
    import vpi
ModuleNotFoundError: No module named 'vpi'

I believe the problem is something about the packages because I don’t have any packages for python-vpi connection.

Index, In this link there are many packages for Jetpack versions.

There are some packages that look like python-vpi stuff. I believe non them of are installed on my system.

For example:

• python-vpi1_1.2.3_arm64.deb
• python-vpi1_1.1.12_arm64.deb
• python-vpi1_1.1.15_arm64.deb

Just searching for “python-vpi” string with CTRL+F in that web page shows many packages like those.

My Jetpack version might not be suitable with these packages because there is no such package under Jetpack 4.5.

When I run dpkg -l | grep vpi command the output says

dpkg -l | grep vpi
ii  libnvvpi1                                     1.0.15                                     arm64        NVIDIA Vision Programming Interface library
ii  nvidia-vpi                                    4.5.1-b17                                  arm64        NVIDIA Vpi Meta Package
ii  vpi1-demos                                    1.0.15                                     arm64        NVIDIA VPI GUI demo applications
ii  vpi1-dev                                      1.0.15                                     arm64        NVIDIA VPI C/C++ development library and headers
ii  vpi1-samples                                  1.0.15                                     arm64        NVIDIA VPI command-line sample applications```

[yasinbedirhansimseq]

Re-installing the whole system and os with Jetpack 4.6 fixed it