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).

47 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
6
votes
0answers
582 views

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 ...
6
votes
0answers
2k views

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 ...
4
votes
1answer
414 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, ...
3
votes
0answers
304 views

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?
2
votes
0answers
430 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 ...
2
votes
0answers
21 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
votes
2answers
44 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 ....
2
votes
1answer
58 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 ...
1
vote
0answers
16 views

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?
1
vote
0answers
131 views

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 ...
1
vote
0answers
25 views

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 ...
1
vote
0answers
32 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 ...
1
vote
2answers
222 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 ...
1
vote
0answers
18 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 ...
1
vote
0answers
94 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
vote
0answers
27 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. ...
1
vote
1answer
59 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: ...
1
vote
0answers
86 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
vote
0answers
28 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 ...
1
vote
0answers
416 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
vote
1answer
1k 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 ...
1
vote
0answers
1k 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 ...
1
vote
0answers
45 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 ...
1
vote
0answers
140 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
vote
0answers
530 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. ...
0
votes
0answers
9 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: ...
0
votes
0answers
25 views

Dataset for OCR from aerial view using YOLOv5s

The task is to detect rotated alphanumeric characters embedded on colored shapes. We will have an aerial view of the object (from a UAS: Unarmed Aerial System). Something of this sort: (One Uppercase ...
0
votes
0answers
38 views

How to draw a line on video frames using opencv?

I have following code for object tracking and have x and y coordinates in a dataframe for a few frames of the video. I would like to draw a line using these coordinates so that my output looks like ...
0
votes
0answers
19 views

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 ...
0
votes
0answers
17 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 ...
0
votes
1answer
39 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 ...
0
votes
1answer
15 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. ...
0
votes
0answers
10 views

Why do images in Open CV template matching get matched to the templates more than once?

The following code reads the set of input tiff files under tiffile and template tiff files under files and performs template matching on them. After the image gets matched, opencv contour extracts the ...
0
votes
0answers
13 views

Detection of vortex and numbering on basis of rotation

Problem Statement: I have a video of ANSYS Simulation of vortices formed due to flat plate plunging. The video contains vortices (in simpler terms blobs), which are distinguished according to their ...
0
votes
0answers
17 views

Why does model CNN with high accuracy but give low prediction on handwriting input images?

I'm trying to train the CNN model with the MNIST dataset expand with my own images handwriting, so I have merged them together, ...
0
votes
2answers
23 views

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?
0
votes
0answers
224 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: ...
0
votes
0answers
61 views

how to detect bifurcation, trifurcation, and crossover on image with python opencv

how to detect bifurcation, trifurcation, and crossover from the branch point with OpenCV when the input like this Expect output : I'm trying to use binary_hit_or_miss but I don't know how to display ...
0
votes
0answers
58 views

What is the closest interpolation method to INTER_AREA in KERAS for shrinking images

What is the closest interpolation method to INTER_AREA in Keras from the following: nearest, bilinear, bicubic, hamming, box, lanczos. I always used INTER_AREA for shrinking images but for some reason,...
0
votes
0answers
34 views

How does the below calculation help to create a PNG from a floating point depth map?

What is the effect of max_val * (depth - depth_min) / (depth_max - depth_min) in the below function? ...
0
votes
0answers
22 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 ...
0
votes
0answers
133 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 ...
0
votes
1answer
101 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 ...
0
votes
1answer
80 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.
0
votes
0answers
88 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
votes
1answer
514 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.