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Library QUIRC is not linked. No decoding is performed. Take it to the OpenCV repository

I am trying to get a qrcode with opencv, in order to do this I have the following code:
import cv2
import numpy as np
...
data, bbox,rectifiedImage = qrDecoder.detectAndDecode(frame)
...
The code runs ok, but when detect the QRCode and I want get data, I got this
Library QUIRC is not linked. No decoding is performed. Take it to the OpenCV repository.
I tried with pip install quirc, but doesn't work and I installed opencv with sudo apt-get install python3-opencv.
How can I fix this?

The version of OpenCV you get with the apt package is always fairly old. Additionally, there's no guarantee that all the modules (here: the QR decoder) were given the required dependencies (here: quirc). Installing additional packages wouldn't solve this because OpenCV needs them at build time, before packaging.
To get the most recent version, install it via pip:
$ pip3 install opencv-python
There is the opencv-python package that only contains the main modules, and there is opencv-contrib-python, which additionally contains "contrib" modules. The packages are mutually incompatible, so only install one of them.

GLIBC_2.33 not found in raspberry pi python

Error Trace:
ImportError: /lib/arm-linux-gnueabihf/libc.so.6: version `GLIBC_2.33' not found (required by /home/pi/.local/lib/python3.7/site-packages/grpc/_cython/cygrpc.cpython-37m-arm-linux-gnueabihf.so)
Scenario:
I'm using google cloud vision api to detect text in images. The program works fine on laptop but gives the above mentioned error when ran in raspberry pi. I've searched a lot but couldn't find any working solution. I'd really appreciate if any one could let me know how to solve this.

Uninstalling grpcio and grpcio-status (mine had version 1.46.3 installed for both) and installing version 1.44.0 solved it for me:
pip uninstall grpcio
pip uninstall grpcio-status
pip install grpcio==1.44.0 --no-binary=grpcio
pip install grpcio-tools==1.44.0 --no-binary=grpcio-tools
You can check your installed versions with pip list.
Note: installing grpcio and grpcio-status takes a really long time. About 15 to 20 minutes each.
Originally posted here: https://groups.google.com/g/grpc-io/c/vjbL3IdZ2Vk/m/EcKSeD4eAgAJ

GLIBC and the kernel of the OS go hand-in-hand; you basically need a newer version of your OS, if you need a more recent GLIBC
the version of the GLIBC can be quickly found out with the following command:
ldd --version

Have you tried building glibc 2.33+ alongside the glibc that come in raspberry pi? Something along this answer and comments to use buildroot

Error while installing TF Object Detection API

I am trying to install Tensorflow Object Detection API, following those instructions. Everything goes well till the moment I have to run python -m pip install within the models/research directory. It starts collecting and installing the various packages, but when it reaches the installation of tf-models-official, it produces the following error :
ERROR: Cannot install object-detection because these package versions have conflicting dependencies.
The conflict is caused by:
tf-models-official 2.7.0 depends on tensorflow-addons
tf-models-official 2.6.1 depends on tensorflow-addons
tf-models-official 2.6.0 depends on tensorflow-addons
tf-models-official 2.5.1 depends on tensorflow-addons
To fix this you could try to:
1. loosen the range of package versions you've specified
2. remove package versions to allow pip attempt to solve the dependency conflict
I did up a bit of digging online, but didn't manage to find anything in the Github repo of tensorflow or other websites. I am using Tensorflow 2.7.0 and Python 3.9.2, on a Linux 64-bit OS. I also tried with Python 3.7.12 but the same error persisted, while manual installation of tensorflow-addons using pip install indicates that no matching distribution was found.

python-3.10.2-amd64: error
python-3.9.10-amd64: ok
python-3.9.2-amd64: ok
python-3.8.10-amd64: ok
python -m pip install --use-feature=2020-resolver tensorflow
'--use-feature=2020-resolver' could be a good solution.
Did you use "tensorflow==2.5.0"?
Don't use specific version like "==2.5.0".
UPDATE
See https://pypi.org/project/tensorflow/#history
tensorflow 2.8.0 (Feb 3, 2022)
I installed tf 2.7.0 and then when I tried to install object detection, tf was reinstalled into tf 2.8.0. So I thought it is weird but I didn't know that tf 2.8.0 doesn't exist yet when you tried to install object detection.
If you try again, tf will be reinstalled automatically into 2.8.0.

OSError: decoder zip not available

import pytesseract as pt
from PIL import Image
img = Image.open("C:/Users/Abir Khan/Desktop/IIT B/Untitled.png")
text = pt.image_to_string(img)
print(text)

OS: MacOS Catalina 10.15.7
pip version: 20.2.4
requirements.txt: Pillow==2.8.1
Upgrading Pillow via pip install --upgrade Pillow to version 8.0.1 worked for me perfectly.
I have tried several different approaches like installing zlib and lzlib through brew but nothing worked.

It likely only needs the zip decoder to save the jpeg. I think I needed to follow these steps in OS X to preview jpegs.
this might help.
https://stackoverflow.com/a/3544159/8074624

Can't use SIFT in Python OpenCV v4.20

I am using OpenCV v4.20 and PyCharm IDE. I want to use SIFT algorithm. But I get this error. I looked for solutions of this error on the internet but none of them did help me. Do you know the solution of this error? (With pip I can install at least 3.4.2.16 version of OpenCV)
Here is my error:
Traceback (most recent call last):
File "C:/Users/HP/PycharmProjects/features/featuredetect.py", line 7, in
sift = cv.xfeatures2d_SIFT.create()
cv2.error: OpenCV(4.2.0) C:\projects\opencv-python\opencv_contrib\modules\xfeatures2d\src\sift.cpp:1210: error: (-213:The function/feature is not implemented) This algorithm is patented and is excluded in this configuration; Set OPENCV_ENABLE_NONFREE CMake option and rebuild the library in function 'cv::xfeatures2d::SIFT::create'
Here is my code:
import cv2 as cv
image = cv.imread("the_book_thief.jpg")
gray_image = cv.cvtColor(image,cv.COLOR_BGR2GRAY)
sift = cv.xfeatures2d_SIFT.create()
keyPoints = sift.detect(image,None)
output = cv.drawKeypoints(image,keyPoints,None)
cv.imshow("FEATURES DETECTED",output)
cv.imshow("NORMAL",image)
cv.waitKey(0)
cv.destroyAllWindows()

SIFT's patent has expired in last July. in versions > 4.4, the detector init command has changed to cv2.SIFT_create().
If you're not using opencv's GUI, It's recommended to install the headless version: pip install opencv-python-headless

Unfortunately, according to this Github issue, SIFT no longer available in opencv > 3.4.2. Since you're using OpenCV v4.2.0, it's not included even if you have installed pip install opencv-contrib-python as shown in this post. A work around is to downgrade to any previous OpenCV version that includes SIFT (I believe any version below 3.4.3). I've been successful when downgrading to v3.4.2.16.
pip install opencv-python==3.4.2.16
pip install opencv-contrib-python==3.4.2.16
Using your code with v3.4.2.16, SIFT seems to work

I had the same issue previously. I had tried all methods but finally a very simple method work for me which has already answered by many. However, there is a little change in my approach.
Step 1:
Uninstall the previously install opencv library
pip uninstall opencv-python
Step 2:
Install opencv contrib library due to copyright issue. Here, we are using version 3.4.2.17
pip install opencv-contrib-python==3.4.2.17
opencv contrib library installation error
The above figure shows version 3.4.2.16 not found error. Hence, I tried with version 3.4.2.17. If this version doesn't work, try other versions of 3.4.x.
Step 3:
Then run the following
import cv2
sift = cv2.xfeatures2d.SIFT_create()
That's all. It works for me. I hope it works for you as well.

I had the same issue, after a lot of attempts, I tried installing opencv-contrib-python several times, but it worked just today. Just to be sure I installed both opencv-python and opencv-contrib-python.
pip install opencv-python
And
pip install opencv-contrib-python
The version that installed was 4.4.0.46 for both opencv-python and opencv-contrib-python. In case the later versions don't support it (A few of the previous versions didn't support SIFT, the one from a month ago, the latest opencv-contrib-python patch was released on Nov 2nd, 2020).

The solution to your problem should be installing opencv-contrib-python-nonfree (available via pip).
$ pip install opencv-contrib-python-nonfree
As the error states SIFT is patented and therefore not included into OpenCV for license reasons. It's included in the nonfree part.