# Top **URL:** https://forum.opencv.org/top.md [Latest](https://forum.opencv.org/latest.md) · [Categories](https://forum.opencv.org/categories.md) · [Tags](https://forum.opencv.org/tags.md) --- ## [Laser pattern rangefinding using a diffraction grating](https://forum.opencv.org/t/laser-pattern-rangefinding-using-a-diffraction-grating/24564)
**Author:** [@salukikev](https://forum.opencv.org/u/salukikev)\ **Replies:** 10\ **Last updated:** [June 7, 2026, 9:28pm UTC](https://forum.opencv.org/t/laser-pattern-rangefinding-using-a-diffraction-grating/24564 "2026-06-07T21:28:47Z")
Hi all! I’m experimenting with a RPI5-1gb and green laser diffraction grating (nearly coaxial with Pi camera module 3). The goal is to reference the projected pattern, and calculate range and angles based upon the sca… --- ## [Wide-baseline stereo on circles grid, enormous stereo RMS](https://forum.opencv.org/t/wide-baseline-stereo-on-circles-grid-enormous-stereo-rms/24595)
**Author:** [@marisano](https://forum.opencv.org/u/marisano)\ **Replies:** 11\ **Last updated:** [June 26, 2026, 11:48am UTC](https://forum.opencv.org/t/wide-baseline-stereo-on-circles-grid-enormous-stereo-rms/24595 "2026-06-26T11:48:29Z")
Thanks so much for providing this test code! I’ve used it as the basis of my own asymmetric circle grid stereo calibration code. Intrinsic camera parameter determination functions well (0.3 and 0.5 rms error), but when I… --- ## [OpenCV GSOC 2026](https://forum.opencv.org/t/opencv-gsoc-2026/24324)
**Author:** [@Pragya\_Agarwal](https://forum.opencv.org/u/Pragya_Agarwal)\ **Replies:** 0\ **Last updated:** [January 24, 2026, 3:18am UTC](https://forum.opencv.org/t/opencv-gsoc-2026/24324 "2026-01-24T03:18:27Z")
Hi! I am Pragya Agarwal. I have been working on computer vision projects for almost an year now. I have a certification from openCV University and I have already done one summer internship in CVDL where I trained a model… --- ## [Introducing PureCV: A Pure Rust Port of OpenCV](https://forum.opencv.org/t/introducing-purecv-a-pure-rust-port-of-opencv/24409)
**Author:** [@kalwalt](https://forum.opencv.org/u/kalwalt)\ **Replies:** 5\ **Last updated:** [July 6, 2026, 4:51pm UTC](https://forum.opencv.org/t/introducing-purecv-a-pure-rust-port-of-opencv/24409 "2026-07-06T16:51:24Z")
Introducing PureCV: A Pure Rust Port of OpenCV :warning: Experimental Phase: PureCV is currently in an experimental stage. There is no stable release or LTS version yet, and the API is subject to change. We recommend usi… --- ## [Introduce CV DebugMate C++: a VS Code extension for debugging with OpenCV](https://forum.opencv.org/t/introduce-cv-debugmate-c-a-vs-code-extension-for-debugging-with-opencv/24268)
**Author:** [@dull\_bird](https://forum.opencv.org/u/dull_bird)\ **Replies:** 0\ **Last updated:** [December 20, 2025, 9:00am UTC](https://forum.opencv.org/t/introduce-cv-debugmate-c-a-vs-code-extension-for-debugging-with-opencv/24268 "2025-12-20T09:00:33Z")
Hey everyone, As a developer working on SLAM and Computer Vision projects in C++, I was constantly frustrated by the lack of proper debugging tools in VS Code after moving away from Visual Studio’s Image Watch. Staring … --- ## [VS code won't install opencv](https://forum.opencv.org/t/vs-code-wont-install-opencv/24245)
**Author:** [@Fred](https://forum.opencv.org/u/Fred)\ **Replies:** 5\ **Last updated:** [December 11, 2025, 9:14am UTC](https://forum.opencv.org/t/vs-code-wont-install-opencv/24245 "2025-12-11T09:14:20Z")
I have a new computer so have installed python v 3.14, and the newest VS Code IDE. But when I try to install opencv (pip install opencv-python) I get the following. (myvenv) C:\\Users\\xxx\\Documents\\MyPythonFolder\>pip i… --- ## [When will OpenCV support Python 3.14 version, since this version has removed the GIL?](https://forum.opencv.org/t/when-will-opencv-support-python-3-14-version-since-this-version-has-removed-the-gil/24198)
**Author:** [@Neil](https://forum.opencv.org/u/Neil)\ **Replies:** 2\ **Last updated:** [November 13, 2025, 1:14pm UTC](https://forum.opencv.org/t/when-will-opencv-support-python-3-14-version-since-this-version-has-removed-the-gil/24198 "2025-11-13T13:14:13Z")
When will OpenCV support Python 3.14 version, since this version has removed the GIL? --- ## [OpenCV cannot access to UVC camera properties](https://forum.opencv.org/t/opencv-cannot-access-to-uvc-camera-properties/24154)
**Author:** [@Blues\_Traggler](https://forum.opencv.org/u/Blues_Traggler)\ **Replies:** 8\ **Last updated:** [October 29, 2025, 3:47pm UTC](https://forum.opencv.org/t/opencv-cannot-access-to-uvc-camera-properties/24154 "2025-10-29T15:47:16Z")
I’m able to read a USB/UVC camera in python through vc = cv2.VideoCapture(0) rval, frame = vc.read() etc. but I cannot change properties through vc.set(…) which always return False whatever the property is (gain, b… --- ## [Making a desktop app using opencv in java/kotlin on Linux (Ubuntu)](https://forum.opencv.org/t/making-a-desktop-app-using-opencv-in-java-kotlin-on-linux-ubuntu/24239)
**Author:** [@Samuel\_Le](https://forum.opencv.org/u/Samuel_Le)\ **Replies:** 4\ **Last updated:** [August 3, 2026, 8:29pm UTC](https://forum.opencv.org/t/making-a-desktop-app-using-opencv-in-java-kotlin-on-linux-ubuntu/24239 "2026-08-03T20:29:27Z")
Hi, I am trying to make a desktop app in kotlin to experiment with various ideas to analyze videos. However I am unable to get opencv on my app. Things I have tried: importing opencv as a dependency by adding it to m… --- ## [Eye To Hand Calibration Using LeRobot](https://forum.opencv.org/t/eye-to-hand-calibration-using-lerobot/24195)
**Author:** [@Sergio\_Orozco](https://forum.opencv.org/u/Sergio_Orozco)\ **Replies:** 2\ **Last updated:** [July 15, 2026, 10:16pm UTC](https://forum.opencv.org/t/eye-to-hand-calibration-using-lerobot/24195 "2026-07-15T22:16:38Z")
Hello! I am trying to do Eye-to-Hand calibration using a LeRobot SO-101 and stationary Realsense camera. Here is a google drive link which links all the appropriate and necessary information. Link: Opencv Post - Google … --- ## [\[MinGW64 on Win11\]Failed to build OpenCV-Python-headless via pip install](https://forum.opencv.org/t/mingw64-on-win11-failed-to-build-opencv-python-headless-via-pip-install/24176)
**Author:** [@UltraBlackCat](https://forum.opencv.org/u/UltraBlackCat)\ **Replies:** 4\ **Last updated:** [November 1, 2025, 2:14am UTC](https://forum.opencv.org/t/mingw64-on-win11-failed-to-build-opencv-python-headless-via-pip-install/24176 "2025-11-01T02:14:45Z")
Mingw64 on Windows11 Python 3.12.12 \[GCC 15.2.0 64 bit (AMD64)\] on win32 MSYS2 Package ,mingw-w64-x86\_64-python-opencv goes very well with no trouble, However, I was encountered one issue: the import process takes an … --- ## [OpenCV Rodrigues And RVECS](https://forum.opencv.org/t/opencv-rodrigues-and-rvecs/24348)
**Author:** [@khwarizman](https://forum.opencv.org/u/khwarizman)\ **Replies:** 4\ **Last updated:** [March 22, 2026, 12:03am UTC](https://forum.opencv.org/t/opencv-rodrigues-and-rvecs/24348 "2026-03-22T00:03:51Z")
Based On my understanding RVECS - Provide the axis angle representation lets say of the object in the world coordinate system.In short they provide rotation of an angle about an arbitrary axis passing through the origin… --- ## [Detecting the edges of striped fabric on a chessboard](https://forum.opencv.org/t/detecting-the-edges-of-striped-fabric-on-a-chessboard/24217)
**Author:** [@JIN\_PRO](https://forum.opencv.org/u/JIN_PRO)\ **Replies:** 7\ **Last updated:** [December 4, 2025, 7:43am UTC](https://forum.opencv.org/t/detecting-the-edges-of-striped-fabric-on-a-chessboard/24217 "2025-12-04T07:43:00Z")
When detecting striped fabric, my solution performed poorly, resulting in fragmented and incomplete detection. Here are my steps: Grayscale conversion Opening Operation: Denoising Gaussian blur Calculate the … --- ## [Issues on building OpenCV 5.0.0](https://forum.opencv.org/t/issues-on-building-opencv-5-0-0/24690)
**Author:** [@jg98](https://forum.opencv.org/u/jg98)\ **Replies:** 0\ **Last updated:** [August 21, 2026, 3:49am UTC](https://forum.opencv.org/t/issues-on-building-opencv-5-0-0/24690 "2026-08-21T03:49:02Z")
I built couple version of 4.xx successfully but there are some issues on building OpenCV 5 in same way. there is a link error on building gapi, I need to add “ws2\_32.lib” dependency manually the built library format is… --- ## [Opencv camera calibration](https://forum.opencv.org/t/opencv-camera-calibration/24388)
**Author:** [@GaoDa](https://forum.opencv.org/u/GaoDa)\ **Replies:** 5\ **Last updated:** [May 19, 2026, 10:13am UTC](https://forum.opencv.org/t/opencv-camera-calibration/24388 "2026-05-19T10:13:00Z")
As I can see in the offical document，the param discoff of the function “cameracalibration” can only take concern about the tilt angle of the image sensor. If I want to calculate the roll/yaw angle of that，how to do? --- ## [What Constitutes a Good Calibration and Acceptable Variance?](https://forum.opencv.org/t/what-constitutes-a-good-calibration-and-acceptable-variance/24169)
**Author:** [@youndahee](https://forum.opencv.org/u/youndahee)\ **Replies:** 4\ **Last updated:** [November 4, 2025, 6:26pm UTC](https://forum.opencv.org/t/what-constitutes-a-good-calibration-and-acceptable-variance/24169 "2025-11-04T18:26:39Z")
I’m currently studying calibration. When I calibrate with different image sets, the calibration results slightly change, which I understand is natural. My question is, is there a standard for what constitutes a good ca… --- ## [Isolating & Tracking Methane Bubbles from Underwater Video(s)](https://forum.opencv.org/t/isolating-tracking-methane-bubbles-from-underwater-video-s/24345)
**Author:** [@daskinner](https://forum.opencv.org/u/daskinner)\ **Replies:** 4\ **Last updated:** [February 4, 2026, 8:47am UTC](https://forum.opencv.org/t/isolating-tracking-methane-bubbles-from-underwater-video-s/24345 "2026-02-04T08:47:09Z")
Hello, I am tracking gas bubble plumes (CO2/Methane) rising from a seafloor source, filmed in 4K (downsampled to 1080p). There are many different short video clips, taken over the course of 153 days, from a camera stati… --- ## [AR rock climbing wall](https://forum.opencv.org/t/ar-rock-climbing-wall/24138)
**Author:** [@imavirgo](https://forum.opencv.org/u/imavirgo)\ **Replies:** 3\ **Last updated:** [May 30, 2026, 5:41pm UTC](https://forum.opencv.org/t/ar-rock-climbing-wall/24138 "2026-05-30T17:41:27Z")
Howdy folks. I have a strong strategic interest in building something like this; I know Python and basic cpp and js, and I understand the basics of opencv. Any hints? --- ## [HoughCircles - finding false positives - help with parameters?](https://forum.opencv.org/t/houghcircles-finding-false-positives-help-with-parameters/24654)
**Author:** [@descott12](https://forum.opencv.org/u/descott12)\ **Replies:** 6\ **Last updated:** [August 5, 2026, 12:46am UTC](https://forum.opencv.org/t/houghcircles-finding-false-positives-help-with-parameters/24654 "2026-08-05T00:46:15Z")
Hello all. Pretty new to Python and Open CV. The following code is detecting circles that don’t exist. I have tweaked the parameters quite a bit but can’t quite get rid of them. In the image, only the two on the right a… --- ## [\[Help\] Struggling to detect pool pockets and place these pockets in live video](https://forum.opencv.org/t/help-struggling-to-detect-pool-pockets-and-place-these-pockets-in-live-video/24487)
**Author:** [@Acookook](https://forum.opencv.org/u/Acookook)\ **Replies:** 5\ **Last updated:** [May 5, 2026, 6:33pm UTC](https://forum.opencv.org/t/help-struggling-to-detect-pool-pockets-and-place-these-pockets-in-live-video/24487 "2026-05-05T18:33:13Z")
I am working on a master’s thesis project -an augmented-reality training system for eight-ball pool. The goal is to detect the real pool-table state from an overhead phone camera, map balls and pockets into table-plane c… --- ## [Iterative Phase Correlation PR](https://forum.opencv.org/t/iterative-phase-correlation-pr/24234)
**Author:** [@zdenyhraz](https://forum.opencv.org/u/zdenyhraz)\ **Replies:** 1\ **Last updated:** [December 1, 2025, 4:37pm UTC](https://forum.opencv.org/t/iterative-phase-correlation-pr/24234 "2025-12-01T16:37:57Z")
OpenCV already has cv::phaseCorrelate function to find the shift between two images. I am the author of the Iterative Phase Correlation algorithm, which is an extension to this algorithm, that significantly improves sub… --- ## [\[GSoC 2026\] RISC-V Optimizations for DNN Module (Starting with Winograd/Winograd63)](https://forum.opencv.org/t/gsoc-2026-risc-v-optimizations-for-dnn-module-starting-with-winograd-winograd63/24238)
**Author:** [@\_Sk\_iitd](https://forum.opencv.org/u/_Sk_iitd)\ **Replies:** 5\ **Last updated:** [January 5, 2026, 10:55am UTC](https://forum.opencv.org/t/gsoc-2026-risc-v-optimizations-for-dnn-module-starting-with-winograd-winograd63/24238 "2026-01-05T10:55:06Z")
Hi everyone, I am an Electrical Engineering student from IIT Delhi interested in the RISC-V Optimization project for GSoC 2026. My Analysis so far: I have been auditing the modules/dnn kernels and noticed that while AV… --- ## [Build OpenCV 5 with CMake failed](https://forum.opencv.org/t/build-opencv-5-with-cmake-failed/24592)
**Author:** [@Simon1](https://forum.opencv.org/u/Simon1)\ **Replies:** 3\ **Last updated:** [July 1, 2026, 6:59am UTC](https://forum.opencv.org/t/build-opencv-5-with-cmake-failed/24592 "2026-07-01T06:59:12Z")
I build opencv 5 with following command but failed cmake -G “Visual Studio 18 2026” -A x64 -S C:/Github/opencv-5.0.0 -B C:/Github/opencv-5-build -D CMAKE\_BUILD\_TYPE=RELEASE -D BUILD\_CUDA\_STUBS=ON -D BUILD\_JAVA=OFF … --- ## [Trouble building a FULL version of OpenCV (C++) with open source QT5](https://forum.opencv.org/t/trouble-building-a-full-version-of-opencv-c-with-open-source-qt5/24153)
**Author:** [@htartisan](https://forum.opencv.org/u/htartisan)\ **Replies:** 6\ **Last updated:** [October 28, 2025, 8:33pm UTC](https://forum.opencv.org/t/trouble-building-a-full-version-of-opencv-c-with-open-source-qt5/24153 "2025-10-28T20:33:29Z")
I have been trying to build a full version of OpenCV for C++/Windows/x86\_64, that includes QT5 (open source) integration. (I want to use it to help me test some embedded software that I developed.) It has been a real h… --- ## [Stitching without Image Transforming](https://forum.opencv.org/t/stitching-without-image-transforming/24213)
**Author:** [@Prof\_Huster](https://forum.opencv.org/u/Prof_Huster)\ **Replies:** 5\ **Last updated:** [November 20, 2025, 6:27pm UTC](https://forum.opencv.org/t/stitching-without-image-transforming/24213 "2025-11-20T18:27:21Z")
I have IR videos from a drone with very little image distortion or rotation. The video follows small prey (rabbits) and dogs in a field. I am careful not to change the heading or altitude of the drone, and at the height … --- ## [Static linking with vcpkg installation](https://forum.opencv.org/t/static-linking-with-vcpkg-installation/24144)
**Author:** [@mjan](https://forum.opencv.org/u/mjan)\ **Replies:** 0\ **Last updated:** [October 24, 2025, 9:02am UTC](https://forum.opencv.org/t/static-linking-with-vcpkg-installation/24144 "2025-10-24T09:02:57Z")
Hi, this might be one of those beginner questions you guys have seen alot already and you’re probably thinking: “why didn’t the guy just use the search function”, but I did and I couldn’t find a topic regarding both vcp… --- ## [KNN background subtraction algorithm](https://forum.opencv.org/t/knn-background-subtraction-algorithm/24406)
**Author:** [@sdg](https://forum.opencv.org/u/sdg)\ **Replies:** 6\ **Last updated:** [April 22, 2026, 2:58pm UTC](https://forum.opencv.org/t/knn-background-subtraction-algorithm/24406 "2026-04-22T14:58:00Z")
We are implementing a video‑based motion detection feature (detecting all moving objects) on an ARM architecture. When using OpenCV’s KNN background subtraction algorithm, we observe high CPU usage while processing multi… --- ## [Recommended OpenCV version, CMake flags, or pre-built binaries for CUDA 13.2 & cuDNN 9.2](https://forum.opencv.org/t/recommended-opencv-version-cmake-flags-or-pre-built-binaries-for-cuda-13-2-cudnn-9-2/24407)
**Author:** [@emanuele](https://forum.opencv.org/u/emanuele)\ **Replies:** 1\ **Last updated:** [March 27, 2026, 3:52pm UTC](https://forum.opencv.org/t/recommended-opencv-version-cmake-flags-or-pre-built-binaries-for-cuda-13-2-cudnn-9-2/24407 "2026-03-27T15:52:36Z")
I am planning to use OpenCV with CUDA support and I would like some advice on version compatibility, the build process, or alternative solutions. My current environment setup is: CUDA Toolkit: 13.2 (correctly install… --- ## [Failed to parse ONNX model](https://forum.opencv.org/t/failed-to-parse-onnx-model/24494)
**Author:** [@Cawa](https://forum.opencv.org/u/Cawa)\ **Replies:** 3\ **Last updated:** [May 6, 2026, 8:48pm UTC](https://forum.opencv.org/t/failed-to-parse-onnx-model/24494 "2026-05-06T20:48:34Z")
Hello, I’m trying to make a face recognition with OpenCV and ONNX models on a Raspberry Pi 5 but while I’m running my program it can parse ONNX shown as below (I’m using face\_detection\_yunet\_2023mar.onnx and face\_recogni… --- ## [Heap error from cvtColor](https://forum.opencv.org/t/heap-error-from-cvtcolor/24677)
**Author:** [@mael15](https://forum.opencv.org/u/mael15)\ **Replies:** 4\ **Last updated:** [September 16, 2026, 8:39am UTC](https://forum.opencv.org/t/heap-error-from-cvtcolor/24677 "2026-09-16T08:39:06Z")
Hi everyone! Why does this simple code result in a heap error? auto img = std::make\_unique\(); bool success = img-\>LoadFile(wxGetUserHome() + wxT("\\\\Desktop\\\\circleTest.jpg")); cv::Mat src(img-\>GetHeight(), img… --- ## [ArUco relative displacement measurement between markers - precision issues when object rotates](https://forum.opencv.org/t/aruco-relative-displacement-measurement-between-markers-precision-issues-when-object-rotates/24444)
**Author:** [@Ruben\_Mendez\_Valles](https://forum.opencv.org/u/Ruben_Mendez_Valles)\ **Replies:** 5\ **Last updated:** [May 15, 2026, 2:06pm UTC](https://forum.opencv.org/t/aruco-relative-displacement-measurement-between-markers-precision-issues-when-object-rotates/24444 "2026-05-15T14:06:07Z")
Hello, I am working on a project where I need to measure the relative displacement of three ArUco markers with respect to a reference marker (ID 0). One marker fixed on the top as reference, and others placed on the bo… --- ## [Can't Read YUV HDMI IN with VideoCapture](https://forum.opencv.org/t/cant-read-yuv-hdmi-in-with-videocapture/24523)
**Author:** [@KotorIzzZ](https://forum.opencv.org/u/KotorIzzZ)\ **Replies:** 5\ **Last updated:** [June 2, 2026, 2:03pm UTC](https://forum.opencv.org/t/cant-read-yuv-hdmi-in-with-videocapture/24523 "2026-06-02T14:03:54Z")
I am developing on the RK3588 platform. The signal from the HDMI IN interface comes through the device node /dev/video40. When the input signal is in RGB format, cv2.VideoCapture("/dev/video40") works perfectly. However… --- ## [Sub-pixel tracking of an optical fiber tip in microscopy images: Challenges with reflections and drift using Lucas-Kanade](https://forum.opencv.org/t/sub-pixel-tracking-of-an-optical-fiber-tip-in-microscopy-images-challenges-with-reflections-and-drift-using-lucas-kanade/24394)
**Author:** [@luisecheve](https://forum.opencv.org/u/luisecheve)\ **Replies:** 5\ **Last updated:** [March 20, 2026, 10:06am UTC](https://forum.opencv.org/t/sub-pixel-tracking-of-an-optical-fiber-tip-in-microscopy-images-challenges-with-reflections-and-drift-using-lucas-kanade/24394 "2026-03-20T10:06:45Z")
I am working on a closed-loop alignment system for an optical fiber using a microscope (Dino-Lite). The goal is to track the XY coordinates of the fiber tip with high precision to provide feedback to a piezo-stage contro… --- ## [VideoCapture crashes on Windows 11 after KB5077181 update (CAP\_DSHOW heap corruption, MSMF warnings)](https://forum.opencv.org/t/videocapture-crashes-on-windows-11-after-kb5077181-update-cap-dshow-heap-corruption-msmf-warnings/24373)
**Author:** [@Kyrylo\_Semenko](https://forum.opencv.org/u/Kyrylo_Semenko)\ **Replies:** 2\ **Last updated:** [March 12, 2026, 7:01am UTC](https://forum.opencv.org/t/videocapture-crashes-on-windows-11-after-kb5077181-update-cap-dshow-heap-corruption-msmf-warnings/24373 "2026-03-12T07:01:37Z")
I’m using OpenCV, Windows 11 64-bit, and a Logitech C920 PRO USB camera. OpenCV 4.9.0 from https://opencv.org/releases/. Same behavior with version 4.12.0. VideoCapture with CAP\_DSHOW had been working reliably for sever… --- ## [\[Hiring\] AI Systems Engineer — Industrial Computer Vision / Edge AI (Remote US/CA/MX)](https://forum.opencv.org/t/hiring-ai-systems-engineer-industrial-computer-vision-edge-ai-remote-us-ca-mx/24696)
**Author:** [@Jaimz](https://forum.opencv.org/u/Jaimz)\ **Replies:** 1\ **Last updated:** [September 5, 2026, 5:54pm UTC](https://forum.opencv.org/t/hiring-ai-systems-engineer-industrial-computer-vision-edge-ai-remote-us-ca-mx/24696 "2026-09-05T17:54:49Z")
I’m the Executive Chairman of LuxTronic (https://www.luxtronic.ai). We build computer-vision systems that run inside manufacturing plants — cameras, edge compute, inference, networking and industrial equipment. We’re hi… --- ## [calibrateHandEye and calibrateRobotWorldHandEye with 3 dof camera on hand](https://forum.opencv.org/t/calibratehandeye-and-calibraterobotworldhandeye-with-3-dof-camera-on-hand/24133)
**Author:** [@mynickmynick](https://forum.opencv.org/u/mynickmynick)\ **Replies:** 1\ **Last updated:** [November 18, 2025, 1:52pm UTC](https://forum.opencv.org/t/calibratehandeye-and-calibraterobotworldhandeye-with-3-dof-camera-on-hand/24133 "2025-11-18T13:52:17Z")
I need to calibrate a multisensor machine with a camera and other sensors on hand. The camera hand has only 3 deg of freedom (translations x,y,z, NO ROTATIONS) therefore to calibrate the camera I have to acquire a calibr… --- ## [Implementing GTK4 in highgui](https://forum.opencv.org/t/implementing-gtk4-in-highgui/24357)
**Author:** [@AdityaMishra3000](https://forum.opencv.org/u/AdityaMishra3000)\ **Replies:** 4\ **Last updated:** [February 7, 2026, 11:23am UTC](https://forum.opencv.org/t/implementing-gtk4-in-highgui/24357 "2026-02-07T11:23:53Z")
Hi everyone, I’ve been working on a GTK4 backend for HighGUI and wanted to get some feedback before turning this into a formal PR, mainly around scope and whether some of the changes cross lines that shouldn’t be crosse… --- ## [cv2.fisheye.undistortPoints with fisheye camera is not working](https://forum.opencv.org/t/cv2-fisheye-undistortpoints-with-fisheye-camera-is-not-working/24344)
**Author:** [@NMO](https://forum.opencv.org/u/NMO)\ **Replies:** 3\ **Last updated:** [February 15, 2026, 3:42pm UTC](https://forum.opencv.org/t/cv2-fisheye-undistortpoints-with-fisheye-camera-is-not-working/24344 "2026-02-15T15:42:26Z")
I want to to estimate the motion of a monocular camera with a fisheye lens. The camera is a Raspberry Pi cam with 222° fisheye lens. The image resolution is 640x480. I calibrated it using cv2.fisheye.calibrate(). I undi… --- ## [RaspberryPi 4 with Trixie X Wayland question](https://forum.opencv.org/t/raspberrypi-4-with-trixie-x-wayland-question/24258)
**Author:** [@jogl](https://forum.opencv.org/u/jogl)\ **Replies:** 1\ **Last updated:** [December 16, 2025, 4:11pm UTC](https://forum.opencv.org/t/raspberrypi-4-with-trixie-x-wayland-question/24258 "2025-12-16T16:11:01Z")
I am setting up a RaspberryPi4 with 4 Mb RAM to run OpenCV. It will be running on an isolated safe LAN headless. I am using Vinagre VNC client on a number of computers to access a number of other headless RPi’s. The n… --- ## [Why are the stubs for OpenCV's Python bindings still so incomplete?](https://forum.opencv.org/t/why-are-the-stubs-for-opencvs-python-bindings-still-so-incomplete/24377)
**Author:** [@ho1\_tian](https://forum.opencv.org/u/ho1_tian)\ **Replies:** 2\ **Last updated:** [February 28, 2026, 1:25am UTC](https://forum.opencv.org/t/why-are-the-stubs-for-opencvs-python-bindings-still-so-incomplete/24377 "2026-02-28T01:25:53Z")
I think solving this problem is not difficult, but I don’t understand why it hasn’t been resolved until now. The following are my proposed solutions to this problem: types-opencv-python Generated based on pyopencv\_sig… --- ## [cv::VideoCapture.isOpen() returns TRUE even on some errors (bug?)](https://forum.opencv.org/t/cv-videocapture-isopen-returns-true-even-on-some-errors-bug/24512)
**Author:** [@dave-007](https://forum.opencv.org/u/dave-007)\ **Replies:** 1\ **Last updated:** [May 19, 2026, 4:15pm UTC](https://forum.opencv.org/t/cv-videocapture-isopen-returns-true-even-on-some-errors-bug/24512 "2026-05-19T16:15:38Z")
i’m very new to opencv, so i don’t know if this is expected behaviour or not (but it’s certainly not intuitive…). it seems that when trying to read an MP4 video, even though openh264 returns an error (and emits it to th… --- ## [EU AI Act compliance](https://forum.opencv.org/t/eu-ai-act-compliance/24607)
**Author:** [@Namrata\_Raina](https://forum.opencv.org/u/Namrata_Raina)\ **Replies:** 2\ **Last updated:** [July 10, 2026, 4:49am UTC](https://forum.opencv.org/t/eu-ai-act-compliance/24607 "2026-07-10T04:49:46Z")
@philnelson Does OpenCV 4.5.3 and OpenCV 4.13.0 comply with the EU AI Act? --- ## [Can't get waitKey() to work](https://forum.opencv.org/t/cant-get-waitkey-to-work/24257)
**Author:** [@jogl](https://forum.opencv.org/u/jogl)\ **Replies:** 3\ **Last updated:** [December 16, 2025, 4:09pm UTC](https://forum.opencv.org/t/cant-get-waitkey-to-work/24257 "2025-12-16T16:09:36Z")
My head is getting sore. What am I doing wrong? This: import cv2 print(“here”) cv2.waitKey(5000000) print(“jp”) cv2.destroyAllWindows() does not wait whether I have 5,000,000, 0 (zero), or 1 as argument. Just print… --- ## [Microscope/Telephoto Camera Calibration](https://forum.opencv.org/t/microscope-telephoto-camera-calibration/24695)
**Author:** [@XYYY\_S](https://forum.opencv.org/u/XYYY_S)\ **Replies:** 4\ **Last updated:** [September 3, 2026, 7:37am UTC](https://forum.opencv.org/t/microscope-telephoto-camera-calibration/24695 "2026-09-03T07:37:57Z")
Some problems we’re encountering right now: even though the RMS is small in microscope calibration, the stability of each calibration is really poor. When calibrating two sets of data consecutively, the resulting focal l… --- ## [Looking to contribute to OpenCV — GSoC 2027 aspirant with C++ background](https://forum.opencv.org/t/looking-to-contribute-to-opencv-gsoc-2027-aspirant-with-c-background/24486)
**Author:** [@tanishk\_kh\_07](https://forum.opencv.org/u/tanishk_kh_07)\ **Replies:** 1\ **Last updated:** [July 30, 2026, 4:01pm UTC](https://forum.opencv.org/t/looking-to-contribute-to-opencv-gsoc-2027-aspirant-with-c-background/24486 "2026-07-30T16:01:13Z")
Hi, I’m a C++ developer and just built OpenCV from source on Apple Silicon M4. I’m looking to start contributing and eventually apply for GSoC 2027. What areas are currently most in need of contributors for someone start… --- ## [Relative position of two ArUco markers](https://forum.opencv.org/t/relative-position-of-two-aruco-markers/24495)
**Author:** [@konrad818](https://forum.opencv.org/u/konrad818)\ **Replies:** 2\ **Last updated:** [May 5, 2026, 6:05am UTC](https://forum.opencv.org/t/relative-position-of-two-aruco-markers/24495 "2026-05-05T06:05:17Z")
Hi everyone, I need help determining the position and rotation of an ArUco marker relative to another QR marker using stereo vision and OpenCV. Brief introduction I’m working on a 6DOF robot and planning to implement a… --- ## [Cant use yolov10 in ONNX format with opencv](https://forum.opencv.org/t/cant-use-yolov10-in-onnx-format-with-opencv/24321)
**Author:** [@Nazar\_Pankov](https://forum.opencv.org/u/Nazar_Pankov)\ **Replies:** 1\ **Last updated:** [January 22, 2026, 10:21pm UTC](https://forum.opencv.org/t/cant-use-yolov10-in-onnx-format-with-opencv/24321 "2026-01-22T22:21:26Z")
I’ve trained yolov10 model and exported it in .onnx. Then I want to use it in my c++ code, but getting error during processing node with 2 inputs and 2 outputs. Here is full output with this error: \[ERROR:0@0.126\] glob… --- ## [Any other socials I should visit?](https://forum.opencv.org/t/any-other-socials-i-should-visit/24137)
**Author:** [@imavirgo](https://forum.opencv.org/u/imavirgo)\ **Replies:** 1\ **Last updated:** [October 21, 2025, 5:55pm UTC](https://forum.opencv.org/t/any-other-socials-i-should-visit/24137 "2025-10-21T17:55:40Z")
I seem to recall a Reddit but I don’t know how active it is. A discord maybe? Thanks so much Joe --- ## [Matchtemplate SQDIFF has minValue != 0 for identical image/template](https://forum.opencv.org/t/matchtemplate-sqdiff-has-minvalue-0-for-identical-image-template/24518)
**Author:** [@kinram](https://forum.opencv.org/u/kinram)\ **Replies:** 4\ **Last updated:** [May 29, 2026, 4:14pm UTC](https://forum.opencv.org/t/matchtemplate-sqdiff-has-minvalue-0-for-identical-image-template/24518 "2026-05-29T16:14:04Z")
Based on the SQDIFF formula: OpenCV: Object Detection I expected to get a minValue of 0 when the template and the image are identical, because the square difference is 0 for each pixel in each channel, so the sum must b… --- ## [ArUco detection on macOS (AVFoundation → OpenCV 4) intermittently returns no markers — sanity check on params/pipeline?](https://forum.opencv.org/t/aruco-detection-on-macos-avfoundation-opencv-4-intermittently-returns-no-markers-sanity-check-on-params-pipeline/24590)
**Author:** [@jmachler](https://forum.opencv.org/u/jmachler)\ **Replies:** 4\ **Last updated:** [June 17, 2026, 3:19pm UTC](https://forum.opencv.org/t/aruco-detection-on-macos-avfoundation-opencv-4-intermittently-returns-no-markers-sanity-check-on-params-pipeline/24590 "2026-06-17T15:19:43Z")
ArUco detection on macOS (AVFoundation → OpenCV 4) intermittently returns no markers — sanity check on params/pipeline? Hi all — I’m running an ArUco detector on macOS using AVFoundation for capture and OpenCV 4 (Homebr… [Next page](https://forum.opencv.org/top.md?page=1&per_page=50)