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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How can I detect blocks of text from scanned document images
ORIGINAL IMAGE:
GOAL:
I want to separate texts into individual paragraphs by placing bounding boxes over them (as shown above).
I tried it do this via traditional computer vision approach using ...
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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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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 ...
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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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Why image is more blurred through PIL?
I was using PIL library to open an image and then convert it into array later on for DL operations. However I found out that image opened was blurry as opposed to the original image. Why is the image ...
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How can I detect partially occluded objects using Python?
I'm building a computer vision application using Python (OpenCV, keras-retinanet, tensorflow) which requires detecting an object and then counting how many objects are behind that front object. So, ...
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how to apply similarity algorithm(or comparision) of over one million vectors with other one million vectors?
How can I apply similarity algorithm (or comparison) of over one million vectors with another one million vectors?
I am following this pyimage search tutorial but don't know how to scale up the ...
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FREAK feature extraction OpenCV
I want to know how to use FREAK feature extraction in python,
I read the documentation but I need some examples.
I wrote this code :
...
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Identify credit card shape using machine learning
I have to approach this task: identify credit card from an image. I am attaching example image below:
I have to identify and localize the credit card from this image. The real challenge is that the ...
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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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Train ML algorithm to find edges
I have input RGB images as follows:
I have a dataset of manually annotated images highlighting the outline(edges) from the input images I am attaching an example.
My aim is to train a ML algorithm ...
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TypeError: 'tuple' object cannot be interpreted as an integer
I have an image (480,640,3) and I am trying to resize it to (150,150,1). Since my Keras model has been trained on images of shape (150,150,1), unfortunately I cannot seem to resize it using the PIL ...
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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?
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What is the origin of YOLO/darknet coordinates
I am aware of that darknet/yolov3 outputs relative coordinates, would the coordinate (0,0) be at the bottom left, or at the top left?
I am confused as opencv2 seems to have the ...
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How to Extract Information from the Image(PNG)
I'm trying to extract some particular information from the image(png).
I tried to extract the text using the below code
...
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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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What is difference between "cv2.filter2D" vs Keras "Conv2D" function
When I have to sharpen an image using opencv, I use:
...
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What's the difference between Haar-like Features and Haar Cascades?
Are they the same in terms of their algorithm? Or do they differ in their respective detection methods?
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Skin Detection From a Face Image
I have photos of people's faces, and I want to detect each person's skin color for later use. I don't want to use predetermined color ranges, instead I want to determine each person's color and then ...
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Detecting unique icon on video in real time
For a project I am working on I'd like to be able to detect unique icons/barcodes in video footage. Suppose you have 10 people in the frame where each person is wearing a t-shirt with a similar but ...
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Uniformity of color and texture in an image
I am new to the field of deep learning and have a problem in determining whether two images have uniform color and texture. For example, I have a
Master image -
Now, with respect to this image i ...
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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 ...
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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 ...
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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 ....
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Ellipses detecting at the image
I have the following image:
I need to get two ellipses which will 'describe' my 'ring'.
I have the following code at the moment:
...
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Is there a way (like planning algorithms) to draw a successive polyline to fill a specific shape (like triangle)?
there is a specific shape (like triangle) area, i am trying to develop an program to draw a successive polyline inside the triangle to fill the triangle, one line 3 layers
this post demonstrates some ...
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Is it possible to detect a person using facial recognition on the fly?
I am working on a small app for face detection in Python using face_recognition and opencv libraries.
I have trained the data ...
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Classifier not predicting real data
I'm trying to train a classifier to recognize my own signature. This is how I built my classifier
How did I collect data?
Signed on a piece of paper for 50 times and created 50 images out of it.
for ...
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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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illumination problem for face landmark detection
I trained dlib face landmark detection model using ibug and yaleB datasets. Accuracy of the model is dropping when a bright light or a shadow appears on the side face. Used default parameters and ...
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People detection methods
In my problem I want to distinguish people from other shapes in images e.g I want to accurately know how many people are in specific region of image (at least for small number of people, for crowded ...
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cv2.error: OpenCV(3.4.3) (-215:Assertion failed) !empty() in function
Would anyone have a tip on how to fix this empty function error in OpenCV? I am attempting to follow the guides on OpenCV.org
The script will detect a face in an image and draw boxes around ...
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Keypoint matching using HoG and SIFT
I have two images and I've found their keypoints using sift keypoint detector,
Now I have to match their keypoints with HoG features,
I know how to extract HoG description,
but I dont know how to ...
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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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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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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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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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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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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 ...
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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.
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White circles extraction from a little darker background
I'm trying to extract three white circles on the top left corner from the image below:
I've tried to use:
...
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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. ...
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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 ...
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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 ...
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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 ...
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