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
73,452
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Calculate distances in a shape with python
I want to calculate the min vertical distance and max horizontal distance of this image.
Like the lines.
I was trying:
_, binary_image = cv2.threshold(image, 0, 255, cv2.THRESH_BINARY)
...
- 21
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0
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27
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OpenCV findContours() only draws round area around object, doesn't detect actual contour
I am trying to create an automatic instance segmentation dataset generator using Unity and OpenCV for Unity. Basically, the app takes pictures of objects at different angles and lighting situations ...
- 1
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17
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Invert undistortion done in OpenCV (recover the original image)
I have an application where I use a 3D model developed through photogrammetry to map between a 2D -> 3D space and back (3D -> 2D). The photogrammetry software (reality capture) "undistorts&...
- 44
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0
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52
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Floodfill filling part of the image and not all background
I have a screenshot taken from a chat platform and want to fill all the image of the chat in white, including profile pictures of participants while keeping the chat boxes. The code from this Question ...
- 379
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25
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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 ...
- 434
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42
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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 ...
0
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34
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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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0
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38
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I get this error: (-215:Assertion failed) npoints >= 0 && (depth == CV_32F || depth == CV_32S) in function 'contourArea' [closed]
when i run the ros2 run self_driving_car_pkg computer_vision_node
this i'm getting this error from terminal =
area = cv2.contourArea(cnt)
cv2.error: OpenCV(4.10.0) /io/opencv/modules/imgproc/src/...
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0
answers
27
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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 ...
- 318
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0
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54
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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 ...
- 19
-1
votes
1
answer
40
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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 (...
- 109
1
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0
answers
45
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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 ...
- 4,436
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votes
1
answer
73
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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, ...
4
votes
3
answers
179
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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 ...
- 2,308
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37
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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 ...
