Questions tagged [opencv]
Open Source Computer Vision Library (OpenCV) is an open source machine learning library used primarily for computer visions applications. OpenCV contains over 2,500 optimized algorithms (including state of the art computer vision ones).
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Compare two pdfs Visually
I have two pdfs and want to get the differences through visual representation where it will highlight the differences by some color or drawing a box.
What are the ways to perform this activity and ...
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Tracking people problem
I am trying to implement a system for counting people in a building using Python and OpenCV, but I have one problem. The system for tracking people doesn't work very well; it can't track a person all ...
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CNN to estimate a density map of an image, used to predict the object count
I'm trying to count the number of objects (larvae in this case), from a video. The constraint is, I cannot use any ML model, nor can I train my dataset as there are no annotations available.
This ...
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How to get the wattage recorded by a dlsr from an image?
I am doing a physics lab where I need to take photos of a light and the intensity of the light changes. I have the photos but I need to understand how to get the average wattage from the images. There ...
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How to run our python scripts utilizing our device's GPU?
My laptop has NVIDIA GeForce GTX1650 GPU. I want to utilize this GPU to run my Python script. Any help in the form of code would be really helpful. I mean tried researching this so much but I couldn't ...
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Use computer vision to detect door blockage
I want to detect door blockage on a camera. Basically if the exit door is blocked by an object, it detects it as an anomaly. How can we do it? Is it possible to do it using OpenCV?
Remember, it doesn’...
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Highlight specific paragraphs from documents
I have a bunch of documents in which I want to highlight certain paragraphs/keyphrases. I have a list of the most frequently appearing sentences and I want to search for these paragraphs/keyphrases in ...
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How to remove the hotspots from given image by using Python and opencv?
In the picture below there are some regions which are very bright (i.e. more white). Some bright regions are wide and some are narrow or thin. The red box covers one such wide bright spot, and blue ...
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Difference in .copy() vs = for copy image into new variable
First, my 3 separate scenarios and my input image
Scenario 1: Copying input image onto new variable by " = "
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Special criteria for histogram equalization measure
let us consider following code -which reads image, applies histogram equalization procedure and display both result :
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OpenCV add/subtract functions produce different results from numpy array add/subtract
Im trying to brighten and dim an image using OpenCV with two approaches.
Approach 1: Used OpenCV's add and subtract functions to ...
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Get multiple predictions from a knn model
I want to my code to return multiple(5) predictions from my trained knn model. I've tried using predict_proba() but it just returns the probabilities and not the names
Here is my code:
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215
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Tensorflow Text Segmentation or Open CV Text Segmenation
I want to extract text data from the image, however not sure what approach I should take.
Steps successfully performed
Dataset collection
Image Preprocessing done
Image Augmentation done
Final Image ...
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OpenCV isn't processing all the images in a directory
I'm really trying to apply CLAHE to a directory of about 700 images. However, once I manage to get it running, for some reason the code stops before all the images are processed.
When I run it on ...
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Rotating and cropping scanned images with OpenCV2
I wrote a script to take scanned images and crop out the background from them as well as rotate them to the proper orthogonal orientation (my set of images were not initially scanned properly and many ...
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Converting images in a directory into a vector to calculate cosine distances?
I'm currently going through issues in terms of acquiring multiple images at once to convert them to a vector for calculating the cosine distance to get similarity between say an image from the ...
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How to mathematically calculate individual pixel values after each image rotation?
If I have an image that is being rotated using OpenCV in python, about its centre, How do I mathematically calculate the pixel values after each rotation?
A python code for this operation would be ...
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How to solve this ValueError: Dimensions must be equal
I'm trying to train an autoencoder model with colored image samples but I got this error
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How to solve MemoryError problem
I've created and normalized my colored image dataset of 3716 sample and size 493*491 as x_train, its type is list
I'm tring to convert it into numpy array as follows
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Read all files from all the folders
I am using Windows, Jupyter Notebook, OpenCV, Mediapipe, Tensorflow.
Hello. I have a video Dataset with 100 action folders and each folder has 100 videos(.avi). Frames Per Second is 25. I want to read ...
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AttributeError: 'NoneType' object has no attribute 'landmark'
I am on windows, using jupyter notebook, Mediapipe:Holistic Solution, Python, tensorflow.
I am using a Holistic solution and trying to get the left hand, right hand and pose landmarks. I am giving my ...
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Converting RGB values to contour values
I am using matplotlib to generate a filled contour plot, please consider the below example as a sample contour plot. I want to read off the contour values from such a filled contour plot using opencv'...
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Normalizing images with OpenCV (divide by 255)
I'm loading images from my dataset, which are all of resolution 200x200 and in RGB format.
I'm loading them using OpenCV for Python, with the following code:
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error: (-215:Assertion failed) [closed]
I was testing OpenCV with their code provided within the documentation. Unfortunately, I'm facing an unexpected error. I think, it might be due to the newer version that I've. I've tried the fix of ...
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Object Detection, custom dataset, algorithm [closed]
I'm looking for a solution to detect objects and classify them, using a custom dataset.The overall goal is to detcet objects using my webcam.
So far I've wanted to use YOLO in combination with OpenCV, ...
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measure the tracking error on object detection algorithms?
I have done object detection on my video data using trackers such as CSRT, KCF and got the detection part.I have ground truth coordinates (x,y) values for few frames from the original video which ...
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how to make image classification model to detect object and track object in a video
i have built a disaster classification model . now i want to use this classification model to detect ex- cyclone in a video to draw bounding box around it and track the cyclone if possible.is it ...
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OpenCV2 resizing image: recommended size [closed]
I am working on image processing project. I see that it's recommended to resize the image in the data pre processing step.
How do I decide what size to to resize it to? The tutorial I am following ...
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679
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Detection of a specific shape in an image
I want to create an algorithm in order to detect the following shape (in the blue region) in videos or images:
I have no dataset from the corresponding object so I thought that if I define it ...
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207
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How to convert the image into frontal?
I have to complete the project in which I have to apply some techniques or model to images . My aim is to convert the image to frontal/straight when it comes to skewed , sheared or any transformation. ...
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Which library is better to go with for text recognition(CNN+RNN+CTC), OpenCV vs Keras vs Tensorflow?
I want to build a model to recognize text form images, for this purpose I need CNN stacked with Bidirectional LSTM and CTC. I would like to know which library would be better and how?
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Is it ok that my computer vision dataset just is loads of frames and images instead of video?
I am new computer vision and I am having a dataset with consecutive frames of videos. I want to ask that is it okay? How will you deal with it to output a video with some detections?
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Real distance between bounding box centers
Assume that I have a camera pointing in a specific direction. I know the Euclidean distance (Real world distance) of the camera to a fixed point, X (mm). Using ...
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crop part of image from image, change it and put it same place in original image
I have image (think of image of small plant) with bounding box. For data augmentation I want to rotate (45 degrees) the image (plant) in bounding box, and place it at same place in original image. so ...
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Using machine learning to find the most similar image that contains another image
As the title states I want to use ml (maybe some kind of CNN autoencoder?) to find the most similar image (I have a list of 10k+ images) within another image. I am currently just using opencv with ...
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Converting pixel values to temperature OpenCV
I am converting a pixel values to temp (values of a thermal image). But after conversion output image is not except able. Here is my code:
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ImportError: cannot import name 'cv2' from 'cv2' [closed]
I'm using anaconda and installed OpenCV using conda-forge.
conda install -c conda-forge opencv
In my notebook I run this line of code
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error in running exe file after changing .py to .exe
I have changed my python code to an .exe file using pyinstaller and anaconda. In my python script ("untitled.py") I import opencv which I have already installed from source using cmake. ...
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Which openCv function can be used to compute BEV perspective transformation given a point coordinates and the camera extrinsics/intrinsics?
I have the 3x3 intrinsics and 4x3 extrinsics matrices ...
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What is the use of applying img_to_array() after cv2.imread()
In a book, I saw the following code to load images from a directory:
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Object detection stops predicting well according to how I collect the images
On my problem I have to use 4k resolution (3840x2160) to record images and detect qrcodes at the same time. The images I end resizing it to 1920x1080 to save it on disk.
The problem is that if I train ...
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Where is the rotated angle actually located in fitEllipse method?
Main task: I fit the ellipse using the fitEllipse() method and then I'd like to count the rotation angle between the horizontal axis and the major axis of the ...
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Does resizing the image size, reduce the quality of the images in CNN?
I am doing a project for cancer recognition. My data set has hunderds of images but not of equal size. I wanna resize them to the size of the smallest image. But I am wondering do you think using the <...
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Find missing object(s) in image with a priori knowledge about the missing object(s) (w.r.t base image)
Problem Statement:
I am working on developing a method, or borrow/modify/combine existing ones, where given an golden image (reference or base with all expected objects to be present), it is able to ...
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Difference between two images but in certain region only
I have two images, where i need to find the difference. i can easily did with the help of SSIM function. Now i want to find the difference between two images but only selected region (i want to ignore ...
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Cable angle measurement (rotation)
I need to detect the rotation of a cable (degree) in the x-axis with high precision [0.2 (or more) degree detection] from its original state.
Detailed description:
I have a cable that is set in its ...
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Canny edge detection not working on Gaussian blurred images
I am trying to detect edges on this lane image. First blurred the image using Gaussian filter and applied Canny edge detection but it gives only blank image without detecting edges.
I have done like ...
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Facial recognition on offline images
I want to do facial recognition on wide varieties of images captured at various ages of my family members. Below are some of the questions I have.
If a person uses glasses of different types, do I ...
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Object identifaction with trained CV model
I am rather new to Computer Vision and Neural Networks, but I already build the following setup:
I have a robot which crawls through the grass with a live video feed.
I build an OpenCV filtering and ...
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Distance of a people in an image [closed]
What is the best approach to find the distance of a person/people from camera, using an image?
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