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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Python : Feature Matching + Homography to find Multiple Objects

I'm trying to use OpenCV via Python to find multiple objects in a train image and match it with the key points detected from a query image. For my case, I'm trying to detect the tennis courts in the ...
Reward's user avatar
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Importing TensorFlow trained model in OpenCV

I want to import a TensorFlow pretrained model in OpenCV dnn C++ module. How can this be done? Are there any examples available?
Naser Piltan's user avatar
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Difference detection between two images

I am trying to compare two images and detect the difference between them whether in shape or color. -The change in shape: the number of parts has changed ( increased or decreased). -The change in ...
fracv's user avatar
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orientation detection - images of govt. issued documents

Trying to figure out a macro approach to detecting the orientation of documents that works across document types (maybe a pipe dream). We successfully used SIFT to detect orientation in documents ...
Vikram Murthy's user avatar
2 votes
2 answers
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shapes recognition for shapes formed by dotted points

In the image, below right corner there is circle shape and triangle shape made with set of co-ordninates.I have searched extensively in the net for algorithm or approach to classify shape correctly ....
Papasani Mohansrinivas's user avatar
1 vote
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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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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?
maryam mehboob's user avatar
1 vote
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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 ...
Serge de Gosson de Varennes's user avatar
1 vote
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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 ...
venkysmarty's user avatar
1 vote
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292 views

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 ...
mike_gundy123's user avatar
1 vote
2 answers
345 views

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 ...
Akash's user avatar
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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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Detect the presence/absense of simple components from a circuit board using object detection

In this case I have a challenge of inspecting a recently mounted product, using computer vision, to detect the absence of any component that I have to check. For this task, I tried the concept of ...
denisb411's user avatar
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Paragraph extraction from text

I am trying to separate scanned pages of a 3 column book into paragraphs. On the pages there can be images located in an arbitrary location, occupying part of one, two or all three of the columns. ...
dmayilyan's user avatar
1 vote
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134 views

Improve results of image stitching using OpenCV (material science)

I'm trying to improve image stitching results with a series of pictures taken via microscope. The object I've photographed is a 3D printed cube that has a number of repeating shapes on the surface. ...
jsifferman's user avatar
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how to update a face recongition ( e.g facenet)

I'm searching for a face recognition that detects new faces not just faces getting from the datasets, for example, facenet is a project that can detect and recognize a face from labels. I would like ...
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how to resize image without changing DPI in opencv for detecting text and feeding into OCR?

i resized the image using open cv and it changed the dpi of the image from 300 dpi to 90 dpi . What is the correct way to resize image without changing its dpi in open cv . if we feed the resized ...
star's user avatar
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Detect blur image using ssdmobilenet and tensorflowlite

I have clear images of cards vs blurry images of card. My task is to capture photo when the image is not blurry, as you can see from the description I need this code to run in real time on android ...
Ajinkya's user avatar
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Implement and train YOLO 3 with Opencv and C++

I want to implement and train YOLO 3 with my dataset using Opencv and C++. I can't find an example to start with, or a tutorial to explain how to train YOLO with my own data. All of the tutorials I ...
all.west's user avatar
1 vote
0 answers
51 views

Semantic Segmentation using Scipy or Scikit-image

Many days ago I saw a user using scipy function to get region of interest (RoI) in an image using different colors. I believe it was some sort of filter. Now I'm trying to do the same but I'm not able ...
Nikhil.Nixel's user avatar
1 vote
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How to detect only the lane boundaries using Hough transform?

This is my code to detect the lane boundaries. But only one line(left most) is detected here. Is there a way to remove other objects from the picture (remove bushes and trees) and detect only the ...
Kushani5j's user avatar
1 vote
0 answers
892 views

Detecting blinking light on a device

Can anyone tell me good approaches to detect blinking light in a video? The background may change constantly. As of now, the color would remain same but the intensity and angle of vision can change. ...
Vampavi's user avatar
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i got the following error : 'numpy.ndarray' object has no attribute 'detectMultiScale' to show image in python?

...
Maulina Safitri's user avatar
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26 views

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 ...
Watch With Veer's user avatar
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Extracting values from a map image (jpg)

Not sure if this is the right platform but I'm in a bit of a fix here. I'm trying to convert this image(jpg) to a raster wherein, the colormap attached shows the values. I'm aware I need to use openCV ...
Ayushi Sharma's user avatar
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16 views

How to rotate a rectangle which has been formed by cv2.rectangle function

Exactly as the question says. Constraints: You cannot do anything to the image itself. Any and all operations has to be on the rectangle formed.
Academic's user avatar
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Techniques for training a CV model based on PDF markup

Given a PDF of a home blueprint (e.g. https://www.roomsketcher.com/content/uploads/2023/04/blueprint-maker.jpg), what are techniques and approaches for training a CV model to lean how a user would ...
Vendetta's user avatar
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0 answers
7 views

YOLOV4 model training

I can't start my model tutorial. I ran it correctly, I tried it before, but now it doesn't even start. why could it be? Did the update come?
Elif Deniz's user avatar
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0 answers
193 views

Rotation invariant template matching using CNN or openCV??

I have 4000 unique images of sample data from intersections and the start and end point from all lanes (approach and exit lanes) on it. I want to train a neural network on these images to find the ...
max's user avatar
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0 votes
0 answers
198 views

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 ...
ZKS's user avatar
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1 answer
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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 ...
brosefzai's user avatar
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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 ...
Max_GD's user avatar
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0 answers
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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 ...
giantjenga's user avatar
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0 answers
2k views

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 ...
nmorsi's user avatar
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39 views

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 ...
Escanor6's user avatar
0 votes
1 answer
218 views

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'...
Digvijay Rawat's user avatar
0 votes
0 answers
2k views

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: ...
Tegig's user avatar
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0 votes
0 answers
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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 ...
ketan 's user avatar
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0 answers
20 views

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 ...
Adithya Adi's user avatar
0 votes
1 answer
480 views

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 ...
Capdi's user avatar
  • 111
0 votes
1 answer
137 views

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. ...
Hamza's user avatar
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2 answers
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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?
Lucifer's user avatar
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0 answers
1k views

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: ...
Sayantan's user avatar
0 votes
0 answers
90 views

Opencv installation problem

I tried to install opencv using cmake to work with gpu. After installation, I try to confirm installation. So, I open anaconda prompt and python >> then import cv2. However, I got the error of ...
Carol's user avatar
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0 votes
0 answers
408 views

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 ...
soumyajeet's user avatar
0 votes
1 answer
154 views

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 ...
Demon's user avatar
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0 votes
1 answer
438 views

Comparing two images and showing the difference in a new image?

I would like to compare two web pages images using computer vision techniques. Show what are non-unique portions comparing both images. Which part image1 not exist in image2 vice versa.
prashanth's user avatar
0 votes
0 answers
131 views

Orange widget with OpenCV setMouseCallback

I am designing an Orange Widget for facial recognition. I would like to draw a rectangle around faces captured in video by setting mouse events with ...
Vernica Jain's user avatar
0 votes
1 answer
538 views

Bounding box coordinates prediction

How to pass multiple bounding boxes coordinates to CNN model?My goal is to predict the coordinates of texts in an image.
vikram_reddy's user avatar
-1 votes
1 answer
3k views

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 ...
Escanor6's user avatar