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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Canny edge detection not working on Gaussian blurred images
I am trying to detect edges on this lane image. First blurred the image using Gaussian filter and applied Canny edge detection but it gives only blank image without detecting edges.
I have done like ...
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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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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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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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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.
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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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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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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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Get specific object dimensional position from image
I need to get specific object like logo dimensional position from an image. I checked open-cv, pillow package etc but it does not help to me. Can anyone advice which is the best process to do this? Do ...
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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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How to create a model to recognize matching label and ROI with OCR
I am trying to make a model in python using Tensorflow to process the Tesseract OCR to detecting and extracting particular ROI from Image. I want to recognize the particular fields and values from ...
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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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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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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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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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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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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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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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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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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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How to convert photo to a vector drawing
I am using the following code to convert photo to a drawing:
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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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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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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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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 ...
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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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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 ...
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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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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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Prerequisites for openCV [closed]
I am looking to start learning openCV to perform a car detection program. Should I know data science and/or machine learning stuff before going for openCV?
If not, where can I start learning openCV ...
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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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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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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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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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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 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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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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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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does tensorflow use opencv to covert image to numpy array
Does tensorflow use opencv to covert image to numpy array ?
How is feature extraction done in tensorflow ? How is it different from opencv model ?
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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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Calculate image width
In this code below, a picture can be loaded into openCV and then the region of interest RIO can be created by just selecting a box around something with the mouse, then press ...
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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. ...
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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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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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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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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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