Questions tagged [opencv]
OpenCV (Open Source Computer Vision) is a library for real time computer vision. When using this tag, please add a language specific tag (python, c++, ...), if relevant.
opencv
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How to get centers of circles arranged in a grid in specific order in opencv
I have some approximate circles in an approximate grid shape, but there is distortion.
How can I get the centers in the order of left to right, top to bottom?
I tried findCirclesGrid, but I don't ...
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How to identify the similarity(in %) between 2 "Black & White" only images / similarity between shapes ignoring colors?
I've searched all possible related keywords that I can think of, but the results are not really what I'm looking for, as most algorithm I found puts high concern on COLOR.
The idea of my application ...
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Why is OpenCV's matrix addition function not clipping when I add a uint8 variable with a value of 200 to a uint8 variable with a value of 100? [duplicate]
I am working my way through PyImageUniversity and am familiarizing myself with matrix addition and subtraction in Python using NumPy and the OpenCV library.
I have Python 3.11.4, OpenCV 4.10.0-dev, ...
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I get this error: (-215:Assertion failed) npoints >= 0 && (depth == CV_32F || depth == CV_32S) in function 'contourArea'
when I run the ros2 run self_driving_car_pkg computer_vision_node
this I get this error from termiinal =
area = cv2.contourArea(cnt)
cv2.error: OpenCV(4.10.0) /io/opencv/modules/imgproc/src/...
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24
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Find the best convergence point of multiple particules trajectories? [closed]
In my project, I would like to find the best convergence point of trajectories of tracked points (done with cv2.calcOpticalFlowPyrLK...).
I know all the points of each trajectory.
My goal is to find ...
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47
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How to add horizontal lines to the table in image opencv
I want to add horizontal lines to the below image
resultant output should be like:
Any methods on how to work it out, even if there are diff images which don't have horizontal lines.
I've tried ...
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Python - errors when calling cv2.ml.TrainData_create(): - responses data type = 19 is not supported - Expected Ptr<cv::UMat> for argument 'responses'
I am following the following tutorial:
https://www.opencvhelp.org/tutorials/deep-learning/training-models/
Following the instructions using the Caltech-101 dataset, I preprocessed the images (...
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43
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How to extract a rectangle in an image from identified lines
I have thousands of images that look like this:
I need to run an OCR algorithm on the "1930 E.D." column. I find that when I crop the image down to just that column, I get much better ...
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71
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Conway's GOL rules not implemented correctly [closed]
I am using OpenCV and a kernel to count neighbors of each pixel, the pixel's value then becomes the number of neighbors that it has, and then I apply Conway's rules, but the output is not as expected, ...
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165
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Compromise between quality and file size, how to save a very detailed image into a file with reasonable size (<1MB)?
I am facing a small (big) problem: I want to generate a high resolution speckle pattern and save it as a file that I can import into a laser engraver. Can be PNG, JPEG, PDF, SVG, or TIFF.
My script ...
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36
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Create a window in Qt not blocked by modal windows [closed]
I am creating an application in Qt (for Windows), which has a main window and many dialogs, which are opened in modal mode. But I also need to create windows that are not affected (blocked) by the ...
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3
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68
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Extract Shapes from an image with black background
I have a task to bulk extract shapes from an image. The image is with black background and the shapes are with white border.
The main goal is to extract the fruits from the image.
How do you that ...
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39
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How can I build my Flutter app to use Python for OpenCV and Numpy? [closed]
I'm developing a Flutter app for iOS that requires image processing using Python, specifically with OpenCV and NumPy. I'm facing several challenges and would appreciate guidance on the best approach:
...
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OpenCV GStreamer VideoWriter write hangs in a Python multiprocessing Process
I'm working on real-time image processing using a Raspberry Pi camera. To optimize processing times, I'm trying to separate some image transformations and video encoding in a separate Process:
import ...
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Improve signature quality extracted using OpenCV from scanned sheet paper
I extracted a signature from a scanned sheet of paper. Users know there should be only the signature on a white sheet of paper.
I implemented the signature cropping from the uploaded image using the ...
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43
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OpenCV contours sorting x-axis and y-axis
I am working on a python program to solve a wordsearch. I am using pytesseract and opencv to process an image of the wordsearch and the solution will be displayed as a text. The script processes the ...
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63
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Why is the color of the line black if the BGR Code I have is red?
When running this code the desired outcome is for the line drawn to be red but it is drawing a black line. I am confused since I wrote the BGR code for white but it seems that is it is just working in ...
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1
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63
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PS Camera taking too much light on OpenCV
I installed a third-party driver and firmware to use my PS 4 Camera on PC and I need it to do a object detection project. Everything works fine on camera on Windows (the screen resolution looks buggy ...
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41
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I'm getting an "src is not a numerical tuple" for an opencv program I'm developing that works in their official documentation but not for me [closed]
I'm creating a python program and trying to get feed from a camera and then perform a fourier transform on it to see its spectrum. I've been trying to initialize the camera with cv2.imread() but for ...
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29
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OpenCV program cannot detect more than one frame [closed]
I wanted to try using opencv for some simple face recognition (not specific faces, just if it sees a human face or not). I was using this model, installed both opencv and opencv-contrib, and it does ...
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21
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Opencv module dnn inference with batch greater than 1
I want to perform inference using the dnn module of opencv. This is my code:
static cv::Mat inputBlob2;
static std::vector<cv::Mat> outputs2;
cv::dnn::blobFromImages(images, inputBlob2, 1.0 / ...
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how to open windows when ı run the computer_vision.py [closed]
ı didn't open the windows like frame,white_region,extended_midlane.. etc. I think ı wrote the codes correctly. but it can be mistake. I don't know.I'll share my codes with you.
this computer_vision.py
...
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28
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crop document within an image
enter image description here
enter image description here
Hello to everyone. I am working on a project as a student. I have many such documents and my task in the project is to write a function that ...
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OpenCV with a FLIR Lepton
I Have a FLIR Lepton hooked up to a raspberry pi 5. I have been able to confirm the Lepton works, and run it by following the instructions from the GroupGets Github repo.
import cv2
cv2.namedWindow(&...
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CUDA Kernel Taking: Large Amount of Process Memory
I have total 811 images with each RGB image dimension of 1440x1080. Therefore total 3.52 GB. I'm using CUDA v12.2, NVIDIA RTX 3090 GPU, and Visual Studio 2019. I'm facing two issues
After readImage() ...
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1
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59
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How can I optimize the process to find the best 4-sided shape that contains my mask?
I am currently working on a project where I need to detect pool table and pool balls from a video frame.
I then need to recreate the state of the game in a 2D mini-map, and in order to do so I need ...
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40
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Capture image from android camera [closed]
I am working on an application that works with cameras in android using java and android studio.
in python or cpp we can access camera with something codes like this:
import cv2 # opencv
vc = cv2....
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I'm struggling to compile anything with OpenCV using g++ [duplicate]
For some reason none of the commands I try are working.
Command: g++ file.cpp -o file -I C:\Users\Username\vcpkg\installed\x64-windows\include -L C:\Users\Username\vcpkg\installed\x64-windows\lib -...
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26
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Generate graph edges based on region boundaries on image
I want to analyze experiment data of particle packing, and specifically calculate things like coordination number. I've managed to autodetect the centroids of each particle using OpenCV thresholding ...
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39
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Low-latency RTSP stream using OpenCV and ffmpeg seems to ignore flags
I'm writing a Qt6 application in C++ which should display and optionally store mutltiple RTSP streams. Currently, I'm using OpenCV to capture the stream:
m_capture = new cv::VideoCapture("rtsp://...
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