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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).

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). OpenCV was built natively with C++, but includes interfaces for C++, Java, Python, and MATLAB. This software is popular for large-scale commercial, startup, and individual applications.

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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 identify the missing objects and draw a bounding…
TwinPenguins
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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 opencv. I plotted character level bounding…
DGS
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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 image provided below. I looked at the online…
Reward
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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, objects are often overlapping. For example: How…
Mark Presser
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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 box covers one thin bright spot. Thin bright spots…
S. M.
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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 coming out the way it is? and what can be done to…
anon012358
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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 algorithm when I have millions of images to compare.…
Lalit Vyas
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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 : freakExtractor = cv2.xfeatures2d.FREAK_create() keypoints,descriptors= freakExtractor.compute(image,None) but the…
Saha
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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 card can be placed on any background and the color…
Ajinkya
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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 generated ellipse. I'm going to do this using the 3rd returned argument from the…
Demon
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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 which learns how these outlines are mapped. And…
Ajinkya
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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 library. Any suggestions on how to fix this? This…
Zahid Ahmed
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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
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Distance of a people in an image

What is the best approach to find the distance of a person/people from camera, using an image?
Karthik Sunil
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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 y=0 at the top of the image as is usual when working with matrices. Yet…
LMB
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