OpenCV 3.2.0 windows, OpenCL shows devices in C++ but not in python

I am using 2 sample scripts to check if python 3.6 can make use of the OpenCL functionalities of Opencv on windows. I have tried to run a couple of examples related to CAMSHIFT provided in samples...

how to fix 'undefined reference to `main' collect2: error: ld returned 1 exit status'

When I am trying to compile the host code using make command. It gave me this error: `/usr/lib/gcc/x86_64-redhat-linux/4.8.5/../../../../lib64/crt1.o: In function `_start': (.text+0x20):...

Running R from cmd in windows

I'm trying to install rtools, so that I can install another package (Google's causalimpact) and the process has indicated I have a problem with my path environment for R. Main issue I can't run...

compiling c++11 using make command

I am trying to compile my code on CPU using MobaXterm terminal and I use make command to compile my code. But many errors appears starting with the ones bellow. I searched online and understand...

How to go about compiling opencv for 32bit for visual studio 2015

I've been trying to get the 32bit compilation of opencv but am struggling to do so. I have followed the tutorial here but with still no success. I already installed all mentioned programs in the...

Unable to install scikit-learn-intelex in Colab

I failed to install scikit-learn-intelex (ver. 2021.2.2) in Colab. Here was what I did in Colab: shell ! python -m pip install --upgrade pip ! python -m pip install scikit-learn-intelex As a...

Windows PATH variable doesn't work if path of the executable isn't on disc C

I had some needs in setting up the Windows enviroment variable PATH in order to use some executables from console. I wrote path to the executable in the PATH variable, but it doesn't work,...

Can't access webcam OpenCV 3.3 Python 3

OpenCV on Python 2.7 has no problem accessing my webcam. For some reason it can't in Python 3. VideoCapture::read always returns none... I even tried compiling from source. This is my cmake (I...

No cv2.pyd file after cmake build

I am hoping to use additonal algorithms in opencv-contrib in opencv. I am trying to build opencv with the Non Free Algorithms in contrib. I am new to using cmake. I was able to complete the...

Open VideoStream using OpenCV 4.5.1 works on Windows but fails on Docker python:3.9.2-slim-buster for specific IP cam

I have 2 ip cameras - one of Hikvision and another of Provision ISR. Both use Onvif and work on VLC. I've written a simple python script to record images every 5 sec from their video stream. On...

Error building OpenCV 3.0.0 rc1 on Windows 7 (64-bit): Cannot compile/link cv2.pyd for Python 3.4

I am going through some beginner computer vision lessons and I would like to use Python 3.4 instead of 2.7 for the lessons, and I have both versions installed on my computer in C:/Python34 and...

OpenCV 4.4.0 no built-in GPU support?

I am having trouble playing with GPU support in OpenCV 4.4.0 downloaded from https://opencv.org/releases/. The changelog has 23 hits for CUDA. The last one in under 4.4.0. Yet when I run a simple...

OpenCV Can't Access Webcam in Python

Python 3.6.1, opencv-python 4.1.1, Windows 10. Code: import numpy as np from cv2 import cv2 cap = cv2.VideoCapture(0) while True: ret, frame = cap.read() cv2.imshow('frame',...

When I try to compile OpenCv with inference engine enabled, I am getting an error

If I try to build OpenCV 4.0.0 with inferenca Engineen enabled, I am getting this error: 1>------ Build started: Project: opencv_dnn, Configuration: Release x64...

Build and Compile OpenCV with Python and GPU Support on Windows 10 VS2015

As the question title states, I am trying to compile my own binaries for the Python3 OpenCV library on Windows 10, with CUDA support and the contrib files. I have been following this guide on...

OpenCV3.3 CUDA stack smashing

I installed OpenCV3.3 with CUDA in ubuntu 16.04. I tried to build OpenCV with CUDA sample code. Code compile succeeded but I faced following error message when I executed binary. error message...

Errors in building Opencv with extra modules in Visual Studio 2015

I have configured and generated opencv 3.2 with extra modules on CMAKE successfully using a 32-bit compiler of Visual Studio 2015 (vs14). However, when building this project in Visual Studio I get...

Opencv 3.2 Visual Studio Build Error

I have tried too many times to build Opencv 3.2. on VS 2017. Cmake gives me Conf and generation is okey, but when i compile on VS 2017, just 12 packeges is builded. Rest of them gives me error. My...

OpenCv ImgShow Buttons

I had to reinstall anaconda and its relatives. After I done this, opencv imshow buttons(such as zoom, save, etc.) didn't show. I tried to reinstall pyqt5, opencv-python(via conda and pip) but not...

Correct codec to write video with .mpg extension

I am wondering if anyone can tell me what the correct codec is to write .mpg format in opencv. I can successfully write in the .avi format using the following codec...

The possible reason for opencv cannot find .png format images

I just find my opencv cannot find .png format images, but works fine with loading other format like .jpg images. I built opencv4.01 with vs2015. Here below are the CMake configurations I saved...

"Pixel format of incoming image is unsupported by OpenCV" on Jetson Nano

This code cap = cv2.VideoCapture('/dev/video0', cv2.CAP_V4L2) gives > VIDEOIO ERROR: V4L2: Pixel format of incoming image is unsupported by OpenCV Here is the output of v4l2-ctl -d...

OpenCV 3.2 for python with CUDA in Windows

I build opencv3.2 with cmake and Visual Studio 12 (2013) with CUDA support and python3.5. All the libraries were build successfully and I can run opencv commands with python. Here is the output...

cv::parallel_for_ not very big improvement

I'm testing the class cv::ParallelLoopBody for image processing code. I first started implementing the normalization, where I've to divide all the pixels with certain values for each channel,...

C++ openCV - createFisherFaceRecognizer was not declared in this scope

I am trying to make a facerecognizer in C++ using openCV. But keep getting the following errors: 1) cv::face::createFisherFaceRecognizer(int, double), but this gives: main.cpp:(.text+0x6a8):...

Can't execute a simple program using opencv, error "Can't find the entry point of the procedure"

The following code compiles with no error, but when I try to execute it i got "The procedure entry point _ZSt24__throw_out_of_range_fmtPKcz could not be located in the dynamic link library...

opencv - cmake error : No such file or directory on Ubuntu

I have been trying to install opencv from source rather than pip since I could not read a VideoCapture successfully. Installing opencv-3.2.0 on Ubuntu 16.04.3 LTS. Followed the details mentioned...

cv::imwrite causes access violation... sometimes

I was trying out the example on OpenCV Documentation on imwrite, and I seem to have sporadic problems with it. The code below runs most of the time, but every now and then it fails with the...

OpenCV installation with cuda9 error: Makefile:160: recipe for target 'all' failed make: *** [all] Error 2

I am trying to install OpenCV 3.3 on Ubuntu 16.04 with CUDA 9 and Caffe framework. I am following this guide: https://github.com/BVLC/caffe/wiki/Op... I already changed the FindCUDA. cmake and...

cannot load a VIDEO with opencv c++

i'm trying to load a video in c++ by using VideoCapture ( I'm using windows)... the video name is 'A.avi' and this is the path "C:\Users\anton\Desktop\eyeVideos\" searching online I found that the...