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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Change color background of chat screenshot with multicoloured background
I have a screenshot taken from a chat platform and want to change the background of the chat to white, including profile pictures of participants. The code from this Question works fine if the name of ...
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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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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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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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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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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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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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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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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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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 ...
