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Questions tagged [haar-wavelet]

In mathematics, the Haar wavelet is a sequence of rescaled "square-shaped" functions which together form a wavelet family or basis. They are similar to techniques used in facial recognition.

In mathematics, the Haar wavelet is a sequence of rescaled "square-shaped" functions which together form a wavelet family or basis. Haar-like features are digital image features used in object recognition. They owe their name to their intuitive similarity with Haar wavelets and were used in the first real-time face detector.

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Refining Haar detection

I'm trying to make a hand detection program by using OpenCV and Haar cascade. It works quite well but it's very jerky. So I'm asking myself if this is a trouble of the haar file that would be too 'cheap' or if there's a way to refine the detection…
Benoît Lahoz
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Hand gesture recognition using haar training and hidden Markov model

I am doing a project on hand gesture recognition using hidden markov model (HMM). For the detection of the hand, I have narrowed down to two techniques: haar training and skin color based detection. Haar training looks more promising, could you…
Vanya
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Converting CWT from MatLab to Python

I am working on converting the following MatLab code into Python: function [pos,dx]=cwt_local_maximum(x,hpw) dx = -cwt(x,2*hpw,'haar'); pos=find(sign(-sign(diff(sign(dx))+0.5)+1))'; end I have investigated different means to achieve this…
TimeTravelPenguin
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Implementing Haar wavelet in python without packages

I am trying to write a code to implement discrete wavelet transform (haar wavelet dwt) without using packages in python. So far I've found a link where they implemented something similar, the link Is this wavelet transform implementation correct?.…
Siddhant Samal
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what values of an image should I use to produce a haar wavelet?

I currently have a Java program that will get the rgb values for each of the pixels in an image. I also have a method to calculate a Haar wavelet on a 2d matrix of values. However I don't know which values I should give to my method that calculates…
user643290
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Discrete wavelet transformation on image using 'haar' wavelet in python

I am trying to apply haar wavelet on an image in python. Here is the code from pywt import dwt2, idwt2 img = cv2.imread('xyz.png') cA, (cH, cV, cD) = dwt2(img, 'haar') Then I modify coefficients embedding some data like given…
Shaan
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matlab implementation of DWT using matrix multiplication?

i'm trying to implement the haar wavelet transform of a 128×128 lena image by multiplying it by the transform matrix H as below: x=imread('lena.jpg'); x=imresize(x,[128…
zahraesb
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Input to the Haar Wavelet Transform is not power of 2

If the input data is not even, what should I do? And what if the input data is not power of 2? Should I just ignore the rest of the numbers?
Yuhang Lin
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Haar Transform matric from Matlab to Python

i've recreated a code of Haar Tranform matrix from matlab to python it's a success upon entering the value of n for 2 and 4 but when i'm trying to input 8 there's an error "Traceback (most recent call last): File "python", line 20, in ValueError:…
r0selle
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Parallelize C code for 2D Haar wavelet transform with OpenMP

This is my first question. I'm trying to parallelize with openMP a 2d haar transform function in C. I obtained it here and modified accordingly. The program takes a black&white image, puts it into a matrix and computes one level of the haar wavelet…
p_koelio
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Haar wavelets - Partial signal reconstruction

I'm trying to approximate a time series/vector usind dwt. I can apply the full dwt and idwt reconstruction, but i don´t know how to reconstruct/approximate the original signal based on just a few coefficients (not all). I tryed…
Nelson
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Are Wavelet Coefficients simply the pixel values of decomposed image in 2D Discrete Wavelet Transform

I've been working with Discrete Wavelet Transform, I'm new to this theory. I want to access and modify the wavelet coefficients of the decomposed image, Are those wavelet coefficients simply the pixel values of the decomposed image in 2D DWT? This…
mfathirirhas
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matlab discrete wavelet transform wfastmod in wmulden

I am interested to derive the discrete wavelet transform for noise reduction of more than 50,000 data points. I am using wmulden - matlab tool for wavelet tranform. Under this function, wfastmcd, an another function is being called which takes only…
Mambo
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Haar Lifting scheme

I am trying to apply lifting scheme version haar to an image. I started to apply it using the code posted on the internet: image = imread('cameraman.tif'); % Applying Lifting scheme lshaar = liftwave('haar'); els = {'p',[-0.125…
Christina
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compressive sensing and Haar wavelet

I want to use CS to reconstruct an image from fewer samples. I use Gaussian random matrix as measurement matrix. My problem is with Psi matrix which I want to be Haar wavelet coefficients but I don't know how to define it. I have used DCT and…
Haybert Markarian
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