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Questions tagged [threshold]

The starting point for a new state.

715 questions
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Clusters merge threshold

I'm working with Mean shift, this procedure calculates where every point in the data set converges. I can also calculate the euclidean distance between the coordinates where 2 distinct points converged but I have to give a threshold, to say, if…
Federico Catalano
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Double Thresholding with opencv

I'm writing code using visual c++ with opencv libraries. Can I do a double threshold on a grey image (like a band pass)? For example I want to set at MaxValue all the level between 100 and 176 and at Zero all the remaining values. Is it possible…
tiavec88
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Improve the quality by applying adaptive threshold in javacv/opencv ?

I'm try to improve my image quality by applying following shareholding to input image. CvSize sz = cvSize(img.width(), img.height()); IplImage gry = cvCreateImage(sz, img.depth(), 1); cvCvtColor(img, gry, CV_BGR2GRAY); …
LkDev
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Detect the circle and measure pixels

In this image I need to detect the vehicle rims and measure the pixel length of the rims via image processing. I think I should follow the circular Hough Transform for circles. can you guys please advice me which steps to follow to acquire the…
Visuddha Karunaratne
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Vega-Lite gradient for line chart

I would like to colour a line above a certain threshold in one colour and below the threshold another colour (see image below). How would I go about doing this? I've tried using gradients and the colouring of the line works fine but I cannot figure…
pac w
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Photoshop like Magic Wand for selecting pixels of a similar color, but in VB.NET

Im a noob. I need to write some vb.net code that looks at a picture and "removes" the blackish pixels. Here's the scenario. A wound care doctor takes a picture of a persons hand on a flat bed scanner. The nice pink palm print is there but it is…
BlueStar
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Fill between two horizontal lines thresholds in matplotlib

Dears, I need to make a fill between two thresholds in my chart I have tried with my code but it does not display, could you please tell me what I am doing wrong? I would like my figure like contour red like figure 2 fig = plt.figure(figsize=(15,…
Juan Carlos
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Finding consecutive values beneath a threshold

I am trying to write some code to define some boundary layers. The data is arranged in the table like this (but there are many more rows): Depth (um) Replicate 1 (O2 Sat %) Replicate 2 (O2 Sat %) Replicate 3 (O2 Sat…
Achilles_03
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Best way to choose a threshold for a multiclass classification problem

I have build a model using Keras. My main aim is to classify animals belonging to 10 different categories. The model is performing well. However, when I am testing the images with non animal images, the model is trying to fit the image between the…
ndr
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Extract text from image using pytesseract in two-tones background

I'm trying to extract text from an image using pytesseract on Python. This is the image where I want to extract the text: Original Image This is the image after applying threshold: Image with threshold Console Output: 20 hours 20…
Kyokko
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set movmean values to NaN if large number of original data points in window are missing

I have a 1-d data file with occasional NaN values. If I apply movmean to this input data, is there a simple way to set the movmean value to NaN if the number of input values within the moving window is greater than a threshold value? For example,…
Jim W
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R Tuning Binary Prediction Threshold

I am running a multilevel binary logistic regression (MLBLR) model using glmer. After having trained the MLBLR on the training data (which was created using Tidymodels), I now intend to tune/calibrate the prediction probability threshold. I hereby…
LB.
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R: create boolean matrix based on data matrix and thresholds data frame

Say I have a data matrix like this one: > data(mtcars) > my_mat <- as.matrix(mtcars[,1:7]) > head(my_mat) mpg cyl disp hp drat wt qsec Mazda RX4 21.0 6 160 110 3.90 2.620 16.46 Mazda RX4 Wag 21.0 6 160 110…
DaniCee
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Pettitt - significance levels in R

I am trying to implement the Pettitt test on R. I am coding by myself but with the reference of the built-in function pettitt.test of R.(https://www.rdocumentation.org/packages/trend/versions/1.1.4/topics/pettitt.test) I could implement it…
Sss
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OpenCV - Draw contours on fingers using convex-hulls & adaptive thresholding

I am pretty new to OpenCV and am trying to achieve drawing simple contours along the outline of my hand using a webcam. I decided on using cv2.adaptiveThreshold() to deal with the different light intensities when the camera adjusts to the hand…
itsolidude
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