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Questions tagged [calibration]

Use this tag for questions related to the process of adjusting the output or indication on a measurement instrument.

443 questions
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Model Probability Calibration in Pyspark

I am using PySpark to implement a Churn classification model for a business problem and the dataset I have is imbalanced. So when I train the model, I randomly select a dataset with equal numbers of 1's and 0's. Then I applied the model in a…
ekorkmz
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flutter package - compass calibration

Is there a way in Flutter Dart to calibrate the sensors of a mobile phone? In my case I need the compass sensor. This is because I am developing an app with the help of one of the Flutter compass packages (flutter_compass…
Mike Noon
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Calculate Intrinsics for a Thermal Camera?

I"m using a Thermal camera for a project and I'm a little stumped so as to how to think about calculating intrinsics for it. The usual camera's would determine different points on a chessboard or something similar, but the thermal camera won't…
sparkFinder
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How to get the 3D position from a 2D with opencv

I'm trying to get the 3D coordinates and orientation of an object from its projection onto an image with a single camera with openCV. I have been reading and the steps to follow are: calibrating the image to get the rotational and translational…
Juan Alvarez Fernandez
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h2o.ai Platt Scaling calibration

I noticed a relatively recend add to the h2o.ai suite, the ability to perform supplementary Platt Scaling to improve the calibration of output probabilities. (See calibrate_model in h2o manual.) Nevertheless few guidance is avaiable on the online…
Giorgio Spedicato
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Camera Calibration: How to do it right

I am trying to calibrate a camera using a checkerboard by the well known Zhang's method followed by bundle adjustment, which is available in both Matlab and OpenCV. There are a lot of empirical guidelines but from my personal experience the accuracy…
user3667089
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iPhone Accelerometer calibration

How do I properly calibrate the accelerometer for my iPhone game? Currently, when the phone is on a flat surface, the paddle drifts to the left. High or Low Pass filters are not an acceptable solution as I need complete control over the paddle even…
user2393462435
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ios magnetometer: force display of calibration view

As an user of a mechanical compass, I noticed that the heading that the magnetometer delivers, is often off by 45 degrees or more, although the calibration display did not appear in that cases. If I test, or use my app outdoors, I ever calibrate the…
AlexWien
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How can I display a 5mm grid at the proper scale in a web browser?

I'm creating a web application for displaying ECGs, which are conventionally drawn at fixed scales (10 mm/mV and 25 mm/s) on a 5mm square grid. It's important to use the correct size, because readers compare what they see on-screen with other ECGs…
GBM
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Distortion correction with open CV

I am trying to correct image distortion with open CV. The theory for the distortion I am trying to correct is a combined barrel and pincushion distortion like this: I am not working with a normal camera here, but with a galvanometer scanning system…
user3696412
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Calibration of magnetometer doesn't give expected results

I want to have a "compass heading" (I want to know the angle upon the north) using a magnetometer. I have seen on several tutorials that first, I need to calibrate it. When I looked up on how to do it I saw graphics comparisons of magnetometer value…
MelKoutch
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Real-time camera self-calibration OpenCV

I'm developing an augmented reality application - a virtual try-on, using OpenCV + OpenGL + QtCreator - and I'm stuck now at calibrating the camera. I found a lot of resources about the calibration process in OpenCV using the chessboard pattern, but…
joanna
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How does Kinect calculates depth?

I'm getting a little bit confused here. How does Kinect calculates depth: What I understand is that The IR projector throws out a pattern which is reflected back and read by the IR camera. Now the IR camera knows the pattern for a particular depth.…
Shashwat
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How to simulate distortion with opencv based on real data, generated by camera calibration (C++)?

I am looking for a way to create (barrel) distortion with OpenCV in C++ that is based on real camera data, that are generated by camera calibration. So my target is to simulate real lens distortion with opencv. Therefor I calibrated a camera with…
user2428883
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Touch screen calibration values, How is it done in Android/Kernel?

I'm porting Android Gingerbread to my custom board (with a Samsung S5PV210 processor). I have a touch screen with an ESC7000 chip. I found a driver in /kernel/drivers/input/touchscreen/usbtouchscreen.c . It almost worked but the bit range, order and…
Sylvain Huard
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