python cv2 calls from c++
Hi, I have embedded python in my c++ code. All other modules work fine, except for the `cv2` module. Any call to `cv2` functions hangs. For instance `cv2.imread` I'm using python 2.7.12 Here is the...
View ArticleError loading OpenCV4 libraries after cross compiling: No such file or directory
I'm having problems to load share libraries after cross-compiling my C++ code using Docker Buildx, having a Raspberry Pi Zero W as the target. After I perform the build, I copy the generated binary to...
View ArticleDistortion correction
I've some unknown distortion like in the picture below, is there any solution to solve those distortion based on lines or squares for example? 
View Articlecompare two pictures of color
Hi, Whats the best method to compare two pictures of mainly black color , (or two pictures of mainly red color) I'm looking at a specific location on an image and am hoping to see a black colored wire...
View Articlec++ imread filepath in windows
Greetings, I've tried to google this to no avail. Please help me understand what is wrong with this file path: Mat lena =...
View ArticleCapture Video from Camera using cv2.VideoCapture(0) not working
Hi, I am trying to execute the following code regarding video capture from webcam on my laptop. I am using Python3 with OpenCV4 on windows 7. import numpy as np import cv2 cap =cv2.VideoCapture(0)...
View ArticleIs it possible to use tee in gstreamer pipeline inside VideoCapture() API?
I am trying to use same camera source for reading frames using opencv `videoCapture(`) API and RTMP streaming.For this I am using tee in gstreamer pipeline inside `Videocapture ()` api as shown below:...
View ArticlecreateVideoReader > 4096 px
Hello, I am currently developing a program for the distribution of video (or others) on giant LED screens. Some video exceeds 4096px and I can't open them via the "cv::cudacodec::createVideoReader"...
View Articleglobal /io/opencv/modules/videoio/src/cap_v4l.cpp (880) open VIDEOIO(V4L2):...
I keep getting this error when I run this code on the ubuntu bash 18.04 terminal: Here is my code, the tensorflow part works just fine it's only the opencv part that is giving me an error. import cv2...
View ArticleWhy GaussianBlur is not multi-core on 32bit OS?
Hi. It's really strange to see that GaussianBlur works single-threaded on 32bit OS while it works multi-threaded on 64bit OS! I have built OpenCV 3.4.5 with TBB on both the operating systems. The CPU...
View ArticleWINDOW_NORMAL worked weird after uncheck WITH_QT
hi, not sure whether Qt has something to do with this, I took a look at the qt window of opencv by make the opencv from source with "WITH_QT" flag and find that the qt window block my right mouse...
View ArticleTrack Edges and get Camera Transformation
I am looking for advice what the best approach would be to achieving my goal. This is my first project using opencv so sorry for the noob questions, I am learning. The goal: I want to use webcam to...
View ArticleExtract secondary video streams
Hello, Some video formats (e.g. mkv) can contain multiple video streams. How do I extract the number of video streams in a video and the secondary video streams themselves, with OpenCV? Thanks!
View ArticleHow to develop a model to detect a point crossed a line?
# How to develop a system which detects if a object crosses a line. I am developing a system, basically which tells a object crossed a line. Do I need to get the camera calibration matrix ? Do I need...
View ArticleOptimize CSRT tracker?
I'm new to OpenCV and was hoping that someone more experienced might be able to point me in the right direction. I'm doing motion tracking on black-and-white videos of insects in flight. Running CSRT...
View ArticleImporting Bidirectional LSTM model via onnx shows an error
Hi, I'm trying to export model from [easyOCR](https://github.com/JaidedAI/EasyOCR) to ONNX and import it through openCV. I successfully exported it to ONNX, checked that it runs well, but failed to...
View ArticleDisable file system cache during imwrite
I am trying to build a application with opencv and c++ in Linux env to capture and save 10000 images, But after saving 800 images System buff/cache is increasing and application running slow (system...
View ArticleHow do you identify if the image is cut at the edges using OpenCV?
 Using OpenCV I would like to identify the above image is incomplete due to the right hand side edges are cut. Below is the code I tried...
View Articleerror importing cv2 in python3.6 but it works for python2.7
Error I get when using python3.6 >>> import cv2 Traceback (most recent call last): File "", line 1, in ImportError: /usr/local/lib/python3.6/dist-packages/cv2.so: undefined symbol:...
View Articlewhich is better for opencv ,C++ or java to doing image processing in android...
i want to make a project an android apps with help mage processing with openCv .Now i am confused what i should select for doing this project android ndk or sdk ,which is better for opencv C++ or Java...
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