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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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Haar Cascades vs. LBP Cascades in Face Detection

I have been experimenting with face detection in OpenCV (Open Source Computer Vision Library), and found that one could use Haar cascades to detect faces as there are several of them provided with OpenCV. However, I have noticed that there are also…
Bojoeb
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Wavelet transform in openCV

did someone tried to implement DWT in opencv or in C++? I saw older posts on this subject and i didn't find them useful for me, because I need a approximation coefficient and details as a result of wavelet transformation. I tried to add this to my…
la lluvia
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How can I detect yawn using Open CV

I am developing an application for iOS that needs to detect when the user yawns. What I did is include Open CV and find faces using a haar cascade, and then find mouth inside the faces (too using a haarcascade). The trouble that I have is that I…
iVela
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What is the best solution for rotation invariant detector?

I'd like to create an object detector based on cascade classifier, the only problem is that LBP and Haar features are not rotation invariant. The first thing that comes to my mind is to rotate the training sample at different angles, but I doubt…
lizarisk
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How to use Haar wavelet to detect LINES on an image?

So I have an image like this: I want to get something like this (I haven't drawn all lines I want but I hope you can get my idea): I want to use SURF ( (Speeded Up Robust Features) is a robust image descriptor, first presented by Herbert Bay et…
Rella
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C/C++ Wavelet library, non-GPL

Ideally what I'd like to find is something with a simple, straightforward interface to multiple wavelet categories, like the GSL, but which has a license that lets me use it in proprietary software. The top answer here lists 10 Wavelet libraries,…
Matt Phillips
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How to find out whitePixelValue when person smile?

using CvRect i am able to detect faces coordinate detectFace(IplImage * pImg, CvHaarClassifierCascade * pCascade, CvMemStorage * pStorage) But my problem is How to find out whitePixelValue when person smile ? And what Smile offset is appropriate ?…
Tariq
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How can DWT be used in LSB substitution steganography

In steganography, the least significant bit (LSB) substitution method embeds the secret bits in the place of bits from the cover medium, for example, image pixels. In some methods, the Discrete Wavelet Transform (DWT) of the image is taken and the…
Reti43
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haar training OpenCV assertion failed

I am trying to train a haar-like classifier for pedestrians in OpenCV using 3340 positive images and 1224 negative images. (in a .txt file I keep the negative image names i.e negatives(1).bmp, and in a txt file I keep the positives i.e.…
valentin
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Image size consideration for Haar cascades

The OpenCV Haar cascade classifier seems to use 24x24 images of faces as its positive training data. I have two questions regarding this: What are the consideration that go into selecting the training image size, besides the fact that larger…
angelatlarge
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Explanation of cascade.xml in a haar classifier

It would be best if someone could explain the numbers/values in the cascade.xml entirely. Example in: <_> 3 -8.8384145498275757e-001 <_> …
Yaobin Then
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Soccer ball detection and tracking - using AI techniques?

I've asked a similar question before, but felt my question wasn't really answered. I'm using the Circle Hough Transform to detect and track a ball. However, I now need an extra check to find out whether the detected circle, is in fact, a…
Adam
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Head and Shoulder Detection (looking from the top)

This is my first post here since I cannot find any suitable answer for my research. I want to use openCV to detect the Head-shoulder pattern to be use in some project. Camera setting is in the ceiling directly facing down to be used in apps for like…
mabg
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HAAR wavelet transform in CUDA

I have Tried to Implement the HAAR wavelet transform in CUDA for a 1D array. ALGORITHM I have 8 indices in the input array With this condition if(x_index>=o_width/2 || y_index>=o_height/2) I will have 4 threads which should be 0,2,4,6 and I plan to…
Code_Jamer
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Plotting Haar functions in R

I want to plot Haar functions, which are defined as: h_1_0 = function(t){ if ((t >= 0) & (t <= 1/2)){return(1)} else if ((t >= 1/2) & (t <= 1)){return(-1)} else{return(0)} } Then k-th Haar function is: h =…
alperovich
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