# Python **URL:** https://forum.opencv.org/c/python/7.md?page=2 [Latest](https://forum.opencv.org/latest.md) · [Categories](https://forum.opencv.org/categories.md) · [Tags](https://forum.opencv.org/tags.md) **Page:** 3 --- ## [Convert this candlestick Full chart](https://forum.opencv.org/t/convert-this-candlestick-full-chart/23960)
**Author:** [@Sachin\_Raghavendra](https://forum.opencv.org/u/Sachin_Raghavendra)\ **Replies:** 1\ **Last updated:** [September 7, 2025, 9:54am UTC](https://forum.opencv.org/t/convert-this-candlestick-full-chart/23960 "2025-09-07T09:54:43Z")
convert this full chart --- ## [Thin Plate Spline & Lanczos Interpolation](https://forum.opencv.org/t/thin-plate-spline-lanczos-interpolation/18912)
**Author:** [@Jason\_van](https://forum.opencv.org/u/Jason_van)\ **Replies:** 0\ **Last updated:** [October 7, 2024, 9:02pm UTC](https://forum.opencv.org/t/thin-plate-spline-lanczos-interpolation/18912 "2024-10-07T21:02:05Z")
Hello all! Apologies for past twice in the past couple of weeks. I’ve been struggling a bit on my project regarding aligning astronomical images nonlinearly. I have a question converting from Scikit-Image to OpenCV: I… --- ## [Thin plate spline warpImage produces only zeros](https://forum.opencv.org/t/thin-plate-spline-warpimage-produces-only-zeros/1125)
**Author:** [@pakoun](https://forum.opencv.org/u/pakoun)\ **Replies:** 14\ **Last updated:** [September 4, 2025, 2:52am UTC](https://forum.opencv.org/t/thin-plate-spline-warpimage-produces-only-zeros/1125 "2025-09-04T02:52:37Z")
Dear all, I am trying to warp an image using the thinplatespline but after warping, the image contains only 0 values. I am attaching a working code example and the datasets as well. I hope for some help to show me the r… --- ## [Drift near FOV edges with ArduCam pose estimation (possible vignetting issue?)](https://forum.opencv.org/t/drift-near-fov-edges-with-arducam-pose-estimation-possible-vignetting-issue/23852)
**Author:** [@Costin](https://forum.opencv.org/u/Costin)\ **Replies:** 1\ **Last updated:** [September 3, 2025, 4:49pm UTC](https://forum.opencv.org/t/drift-near-fov-edges-with-arducam-pose-estimation-possible-vignetting-issue/23852 "2025-09-03T16:49:19Z")
Hi, I implemented a multi-view geometry pipeline in ROS to track an underwater robot’s pose using two fixed cameras: GoPro (bird’s-eye view) ArduCam B0497 (side view on tripod) A single fixed ArUco marker is vis… --- ## [Why are images not warped before feature detection and matching in the stitching pipeline?](https://forum.opencv.org/t/why-are-images-not-warped-before-feature-detection-and-matching-in-the-stitching-pipeline/23861)
**Author:** [@mapf](https://forum.opencv.org/u/mapf)\ **Replies:** 4\ **Last updated:** [September 1, 2025, 10:31am UTC](https://forum.opencv.org/t/why-are-images-not-warped-before-feature-detection-and-matching-in-the-stitching-pipeline/23861 "2025-09-01T10:31:30Z")
Hi, so I am new to image stitching. Ultimately, I would like to implement a pipeline for CUDA (which I am also unfamiliar with), but for now, I am trying to implement a pipeline in Python to understand the processes conc… --- ## [findChessboardCornersSB not working, detects only some corners](https://forum.opencv.org/t/findchessboardcornerssb-not-working-detects-only-some-corners/22844)
**Author:** [@Falco\_Peregrinus](https://forum.opencv.org/u/Falco_Peregrinus)\ **Replies:** 2\ **Last updated:** [August 31, 2025, 2:13pm UTC](https://forum.opencv.org/t/findchessboardcornerssb-not-working-detects-only-some-corners/22844 "2025-08-31T14:13:43Z")
Hi. I have pictures of my checkerboard, but findChessboardCornersSB() or findChessboardCorners() cannot detect all corners, only some of them, or none, regardless of checkerboard dimensions that I input. I tried the… --- ## [Delete keypoints by x and y coordinates](https://forum.opencv.org/t/delete-keypoints-by-x-and-y-coordinates/23901)
**Author:** [@NektoN95](https://forum.opencv.org/u/NektoN95)\ **Replies:** 3\ **Last updated:** [August 27, 2025, 4:24pm UTC](https://forum.opencv.org/t/delete-keypoints-by-x-and-y-coordinates/23901 "2025-08-27T16:24:05Z")
I have series of firstperson game screenshots which will be further used for Simultaneous Localization and Mapping. But the thing is, there are elements of interface you cannot hide. So before searching for similar keypi… --- ## [Disparity map colors keep changing when using stereo camera with OpenCV](https://forum.opencv.org/t/disparity-map-colors-keep-changing-when-using-stereo-camera-with-opencv/23897)
**Author:** [@doumiao2](https://forum.opencv.org/u/doumiao2)\ **Replies:** 4\ **Last updated:** [August 24, 2025, 11:22pm UTC](https://forum.opencv.org/t/disparity-map-colors-keep-changing-when-using-stereo-camera-with-opencv/23897 "2025-08-24T23:22:11Z")
Hello, I am a beginner in OpenCV. I am trying to generate a disparity map from a stereo camera and then reconstruct 3D. However, I found that the colors of the disparity map keep changing over time. I have already ruled… --- ## [Removing the jagedness from the image](https://forum.opencv.org/t/removing-the-jagedness-from-the-image/23855)
**Author:** [@Kunal\_Kewat](https://forum.opencv.org/u/Kunal_Kewat)\ **Replies:** 3\ **Last updated:** [August 21, 2025, 8:57am UTC](https://forum.opencv.org/t/removing-the-jagedness-from-the-image/23855 "2025-08-21T08:57:24Z")
i have images like this and i want to remove all the jageddness while keeping the shape. --- ## [Contactless Fingerprint Processing](https://forum.opencv.org/t/contactless-fingerprint-processing/23846)
**Author:** [@Faisal\_Aldoraihem](https://forum.opencv.org/u/Faisal_Aldoraihem)\ **Replies:** 0\ **Last updated:** [August 19, 2025, 3:12pm UTC](https://forum.opencv.org/t/contactless-fingerprint-processing/23846 "2025-08-19T15:12:16Z")
Hi! I’ve been trying to follow these two research papers, Priesnitz et al, and Rathgeb et al to implement and learn about contactless fingerprint capture, but I’ve reached a wall when it comes to processing the cropped … --- ## [Need Help With OpenCV & RTSP - Python](https://forum.opencv.org/t/need-help-with-opencv-rtsp-python/20193)
**Author:** [@Midhun\_M](https://forum.opencv.org/u/Midhun_M)\ **Replies:** 11\ **Last updated:** [February 22, 2025, 2:33pm UTC](https://forum.opencv.org/t/need-help-with-opencv-rtsp-python/20193 "2025-02-22T14:33:46Z")
I’m working on a Python script that reads multiple RTSP streams using OpenCV, detects motion, and saves frames when motion is detected. Initially, I faced issues with ash-colored frames due to H.265 codec, which OpenCV d… --- ## [Possible Solution for creating KCF tracker error](https://forum.opencv.org/t/possible-solution-for-creating-kcf-tracker-error/23782)
**Author:** [@emre06](https://forum.opencv.org/u/emre06)\ **Replies:** 0\ **Last updated:** [August 15, 2025, 2:03pm UTC](https://forum.opencv.org/t/possible-solution-for-creating-kcf-tracker-error/23782 "2025-08-15T14:03:10Z")
Hello Everyone, I have done too much research in internet but finally found a solution myself. If you cannot create tracker suchlike tracker=cv2.TrackerKCF.create() or similar code due in jupyter environment, first you s… --- ## [OpenCV Bootcamp](https://forum.opencv.org/t/opencv-bootcamp/23752)
**Author:** [@uselton](https://forum.opencv.org/u/uselton)\ **Replies:** 3\ **Last updated:** [August 14, 2025, 10:29pm UTC](https://forum.opencv.org/t/opencv-bootcamp/23752 "2025-08-14T22:29:55Z")
Greetings all. I just started. I am following along with the (first of the) bootcamp tutorials. I do not see anywhere if I can get the Jupyter notebooks, or at least their text. I’m trying to follow along at home, and it… --- ## [Can not install dlib for face\_recognition](https://forum.opencv.org/t/can-not-install-dlib-for-face-recognition/23515)
**Author:** [@zamigmammadzada](https://forum.opencv.org/u/zamigmammadzada)\ **Replies:** 2\ **Last updated:** [August 14, 2025, 8:27pm UTC](https://forum.opencv.org/t/can-not-install-dlib-for-face-recognition/23515 "2025-08-14T20:27:46Z")
Hello everyone, I need to download the dlib library for face\_recognition but every time I get this error: “building wheel for dlib (pyproject.toml) did not run successfully” and even though I downloaded the cmake library… --- ## [How to convert rvects to rotation matrix?](https://forum.opencv.org/t/how-to-convert-rvects-to-rotation-matrix/804)
**Author:** [@jknight](https://forum.opencv.org/u/jknight)\ **Replies:** 6\ **Last updated:** [August 14, 2025, 5:42pm UTC](https://forum.opencv.org/t/how-to-convert-rvects-to-rotation-matrix/804 "2025-08-14T17:42:35Z")
I have successfully calibrated a camera using this link: openCV camera Calibration I get the camera matrix, distortion coefficients, rotation vectors (rvects) and translation vectors (tvects). However, the rvects and t… --- ## [OpenCV NPU support](https://forum.opencv.org/t/opencv-npu-support/23725)
**Author:** [@bluedalmatian](https://forum.opencv.org/u/bluedalmatian)\ **Replies:** 1\ **Last updated:** [August 11, 2025, 7:34pm UTC](https://forum.opencv.org/t/opencv-npu-support/23725 "2025-08-11T19:34:08Z")
I read with interest the press release at Working with Neural Processing Units (NPUs) using OpenCV - OpenCV which shows a nice elegant API for handing off processing to an NPU however it only supports the A311D chip curr… --- ## [OpenCV has been ported to MicroPython!](https://forum.opencv.org/t/opencv-has-been-ported-to-micropython/23667)
**Author:** [@unclere](https://forum.opencv.org/u/unclere)\ **Replies:** 0\ **Last updated:** [August 8, 2025, 2:03pm UTC](https://forum.opencv.org/t/opencv-has-been-ported-to-micropython/23667 "2025-08-08T14:03:36Z")
--- ## [Improving stereovision accuracy - debugging consistent plane fitting errors](https://forum.opencv.org/t/improving-stereovision-accuracy-debugging-consistent-plane-fitting-errors/23656)
**Author:** [@eric](https://forum.opencv.org/u/eric)\ **Replies:** 0\ **Last updated:** [August 7, 2025, 8:55pm UTC](https://forum.opencv.org/t/improving-stereovision-accuracy-debugging-consistent-plane-fitting-errors/23656 "2025-08-07T20:55:34Z")
Hi community, I’m trying to improve the results of my stereo vision system, and I’m encountering a strange result when evaluating my system by fitting my checker board pattern to a plane. I’m evaluating my system with t… --- ## [Opencv CHARUCO Detection off by a few mm in simulation](https://forum.opencv.org/t/opencv-charuco-detection-off-by-a-few-mm-in-simulation/23488)
**Author:** [@Khaboom](https://forum.opencv.org/u/Khaboom)\ **Replies:** 19\ **Last updated:** [August 5, 2025, 3:12pm UTC](https://forum.opencv.org/t/opencv-charuco-detection-off-by-a-few-mm-in-simulation/23488 "2025-08-05T15:12:13Z")
Hi, I am trying to using RODODK for OpenCV simulation. However, I am having trouble figuring out why the position is off by a few mm in the x and y. The reprojection is .15 which should be really good. Is my math wron… --- ## ["Failed to initialize Inference Engine backend" on MyriadX](https://forum.opencv.org/t/failed-to-initialize-inference-engine-backend-on-myriadx/13679)
**Author:** [@triangulum](https://forum.opencv.org/u/triangulum)\ **Replies:** 6\ **Last updated:** [August 1, 2025, 5:24pm UTC](https://forum.opencv.org/t/failed-to-initialize-inference-engine-backend-on-myriadx/13679 "2025-08-01T17:24:44Z")
Note: sorry for string links - since I created this account recently, I can’t include more than 2 links in one post. Note 2: this question was originally asked on OpenVINO github. Using OpenVINO 2022.2 with OpenCV 4.7… --- ## [Cant open 2 camera PS3 Eye](https://forum.opencv.org/t/cant-open-2-camera-ps3-eye/23374)
**Author:** [@Gvit0](https://forum.opencv.org/u/Gvit0)\ **Replies:** 5\ **Last updated:** [July 29, 2025, 7:12am UTC](https://forum.opencv.org/t/cant-open-2-camera-ps3-eye/23374 "2025-07-29T07:12:59Z")
I can’t connect 2 PS3 Eye cameras. There are 2 ports via from pygrabber.dshow\_graph import FilterGraph def get\_available\_cameras() : devices = FilterGraph().get\_input\_devices() available\_cameras = {} for… --- ## [Accuracy improvement for 2D measurement using local mm/px scale factor map?](https://forum.opencv.org/t/accuracy-improvement-for-2d-measurement-using-local-mm-px-scale-factor-map/23109)
**Author:** [@maksnikolaev2306](https://forum.opencv.org/u/maksnikolaev2306)\ **Replies:** 3\ **Last updated:** [July 20, 2025, 10:30pm UTC](https://forum.opencv.org/t/accuracy-improvement-for-2d-measurement-using-local-mm-px-scale-factor-map/23109 "2025-07-20T22:30:22Z")
Accuracy improvement for 2D measurement using local mm/px scale factor map? Hi everyone! I’m Maxim, a student, and this is my first solo OpenCV-based project. I’m developing an automated system in Python to measure d… --- ## [Gray frames/lost pixes](https://forum.opencv.org/t/gray-frames-lost-pixes/23174)
**Author:** [@Fellipe\_Zambrano](https://forum.opencv.org/u/Fellipe_Zambrano)\ **Replies:** 11\ **Last updated:** [July 19, 2025, 7:03pm UTC](https://forum.opencv.org/t/gray-frames-lost-pixes/23174 "2025-07-19T19:03:44Z")
Hello guys. I’m using the opencv\_contrib\_python\_rolling-4.12.0.86-cp37-abi3-win\_amd64.whl, to read a video streaming (RTSP link). What happens, is that, usually video is getting gray frames, in part of image or in tota… --- ## [Camera Calibration on a curved surface](https://forum.opencv.org/t/camera-calibration-on-a-curved-surface/22774)
**Author:** [@swanprince](https://forum.opencv.org/u/swanprince)\ **Replies:** 22\ **Last updated:** [July 18, 2025, 5:37pm UTC](https://forum.opencv.org/t/camera-calibration-on-a-curved-surface/22774 "2025-07-18T17:37:50Z")
Hello, I am trying to use OpenCV’s camera calibration to “flatten” images on a concave surface. The camera is statically positioned facing the center of the surface throughout my experiments, so I think I can get away w… --- ## [Microscopy Background Removal](https://forum.opencv.org/t/microscopy-background-removal/23176)
**Author:** [@elimelanson](https://forum.opencv.org/u/elimelanson)\ **Replies:** 1\ **Last updated:** [July 17, 2025, 9:53pm UTC](https://forum.opencv.org/t/microscopy-background-removal/23176 "2025-07-17T21:53:53Z")
We are processing 16-bit .tif images from a microscope camera (Thorcam Kiralux). We are attempting to remove the background generated by the surface of the observed material and be left with only the magnetic domains whi… --- ## [Simple Blob Detector: How is a blob measured?](https://forum.opencv.org/t/simple-blob-detector-how-is-a-blob-measured/23157)
**Author:** [@CCN](https://forum.opencv.org/u/CCN)\ **Replies:** 4\ **Last updated:** [July 16, 2025, 7:35pm UTC](https://forum.opencv.org/t/simple-blob-detector-how-is-a-blob-measured/23157 "2025-07-16T19:35:08Z")
How is a blob measured in Simple Blob Detector? The equation for detecting the blob size seems to be as follows: Math.PI \* (kp.Size / 2) ^ 2) . According to OpenCV: OpenCV: cv::KeyPoint Class Reference it seems kp.Size i… --- ## [Improve eye image quality](https://forum.opencv.org/t/improve-eye-image-quality/15991)
**Author:** [@amosse](https://forum.opencv.org/u/amosse)\ **Replies:** 3\ **Last updated:** [July 11, 2025, 3:37am UTC](https://forum.opencv.org/t/improve-eye-image-quality/15991 "2025-07-11T03:37:46Z")
Hello, Noob and new opencv user here :grin: I made some research for a personal project about eye iris pictures improvement. My goal is to improve quality of existing iris pics, bad quality (low res, glares, blur, bad … --- ## [Streamer / Twitch Recognition](https://forum.opencv.org/t/streamer-twitch-recognition/23003)
**Author:** [@highheat](https://forum.opencv.org/u/highheat)\ **Replies:** 0\ **Last updated:** [July 8, 2025, 11:30pm UTC](https://forum.opencv.org/t/streamer-twitch-recognition/23003 "2025-07-08T23:30:36Z")
(Star on face for anonymity of user) Hi, I’ve tried a couple things to detect streamer’s picture in picture rectangles on things like zoom screenshares or twitch streams, I’ve done everything that gpt recommended lik… --- ## [Hand-eye calibration advice](https://forum.opencv.org/t/hand-eye-calibration-advice/19429)
**Author:** [@starec.vladimir](https://forum.opencv.org/u/starec.vladimir)\ **Replies:** 1\ **Last updated:** [December 12, 2024, 12:08pm UTC](https://forum.opencv.org/t/hand-eye-calibration-advice/19429 "2024-12-12T12:08:48Z")
Hello, I would be very thankful for any advice regarding openCV hand-eye calibration. I am working on robotic station, where I need to pick planary objects using 7-DOF uFactory Robot Robot is equipped with custom gripp… --- ## [Defining the strategy to perform forgery detection](https://forum.opencv.org/t/defining-the-strategy-to-perform-forgery-detection/22860)
**Author:** [@EngelsLeonhardt](https://forum.opencv.org/u/EngelsLeonhardt)\ **Replies:** 5\ **Last updated:** [July 3, 2025, 3:57pm UTC](https://forum.opencv.org/t/defining-the-strategy-to-perform-forgery-detection/22860 "2025-07-03T15:57:00Z")
Hello community, this is my first post here. I am learning to use OpenCV to help me develop a way to identify video forgeries, such as inter-frame forgery detection. For that, I am using the Gunnar-Farneback method to co… [Previous page](https://forum.opencv.org/c/python/7.md?page=1) [Next page](https://forum.opencv.org/c/python/7.md?page=3)