Questions tagged [opencv]

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656 views

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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0answers
47 views

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 ...
3
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1answer
223 views

How can I detect partially obscured 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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0answers
39 views

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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0answers
14 views

orientation detection - images of govt. issued documents

Trying to figure out a macro approach to detecting orientation of documents that works across document types (maybe a pipe dream). We successfully used SIFT to detect orientation in documents where we ...
2
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1answer
31 views

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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2answers
55 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 ...
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0answers
24 views

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 ...
1
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1answer
39 views

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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0answers
45 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. ...
1
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0answers
19 views

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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0answers
101 views

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 ...
1
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1answer
381 views

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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0answers
36 views

Why when I apply GaussianBlur in my images, my model overfit? CNN KERAS

I have 1400 images (700 each class), and i'm using vgg-16 to classificate between one and other class. But when I apply the preprocess method Gaussian Blur (which seem to be very much clear to see the ...
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0answers
37 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 ...
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0answers
55 views

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 ...
1
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1answer
36 views

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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0answers
285 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. ...
1
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0answers
74 views

Recognize polygons and get coordinates on transparent image

I have to implement a program to recognize polygons on transparent images, like this: So, in this picture we have 4 main polygons, we need to recognize them with a blue background and more dark blue ...
0
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0answers
7 views

Finding bounding box coordinates in Object Detection

In some of the OpenCV implementations for object detection , I don't understand how the co-ordinates of the bounding box of an object are extracted from the image. For example , In Object Detection ...
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0answers
12 views

Training images for gender and and age detection from face

Can someone please tell me if it is feasible to train my own set of facial images to detect gender and age without using any cloud architecture or paying some amount of money ? And , on an average how ...
0
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1answer
47 views

Cable angle measurement (rotation)

I need to detect the rotation of a cable (angle) 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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0answers
14 views

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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0answers
10 views

Why did we label optical flow datasets with dense flow fields?

In optical flow datasets like Chairs or Sintel the ground truth is always a dense opticalFlow field. Why don't we have grounds for a per-block motion vector field?
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0answers
12 views

Accurate circles detection

The main task is to detect all seven white circles precisely ( from the image below): The following parameters are known: Radius is (almost) the same for each circle (can differ only a little). ...
0
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1answer
24 views

how to compare two images and show the difference in a new image?

I want 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.
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18 views

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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0answers
15 views

Find an image in a huge list of other images (feature matching, ORB, BRISK, …)

Imagine I have 20k images of different Beer bottles in different situations, positions, orientations,... I would like to find the picture that contains that specific beer I'm looking for, say a Corona....
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0answers
15 views

Image transformation methods

For OpenCV-python. Could anyone illustrate the difference between the image transformation method like cv2.wrapprespective and cv2.prespectivetransform?
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0answers
8 views

Filters to imitate mobile camera noise

I want to train a super-resolution model that I will further apply to text images. The goal is to work with camera-captured images of text, increase the resolution so that the quality of OCR increases....
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0answers
56 views

What should I do with this cv2 error?

here is my code in python : ...
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2answers
11k views

I get this error Expected Ptr<cv::UMat> for argument '%s' while resizing image in open cv2

This is my code: ...
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0answers
10 views

Scenario description of Roads using Deep learning

I want to do scenario description of road. If there are cars, humans infront of the blind person it should describe the scenario and output should be consumable by blind person. Question: Should it ...
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0answers
41 views

What is the best algorithm for object recognition based on its outline/edge in openCV

I am developing an application that needs to recognize objects based on their outline in any condition. So far I can recognize the objects outline if they have a simple background, however if there is ...
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0answers
668 views

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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0answers
64 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 ...
0
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1answer
489 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.