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Questions tagged [haar-classifier]

Visual Neural Network recognizer that breaks up an image into digital image features (nose, mouth, etc) to improve accuracy in object recognition.

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OpenCV detectMultiScale() minNeighbors parameter

I'm currently using Haar classifiers, to detect objects. On my way, I didn't understand what is the minNeighbors parameter, what is it representing? Actually I don't understand what are the neighbors of the detection candidate rectangle. Please can…
blakeO
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Java and haarcascade face and mouth detection - mouth as the nose

Today I begin to test the project which detects a smile in Java and OpenCv. To recognition face and mouth project used haarcascade_frontalface_alt and haarcascade_mcs_mouth But i don't understand why in some reasons project detect nose as a mouth.…
Adamo
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OpenCV Haar Classifier result table explanation

I am trying to create a Haar classifier to recognise objects however I can't seem to figure out what the results table that is produced at each stage stands for. E.g. 1 ===== TRAINING 1-stage =====
Colin747
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Getting the confidence level of detectMultiscale in OpenCV with Python?

I'm using a trained opencv cascade classifier to detect hands in video frames, and would like to lower my false positive rate. Reading up on the net, I saw you can do so by accessing the rejectLevels and levelWeights information returned by the…
RonenKi
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How to use openCV and HAAR Cascades to blur faces?

I would like to know is there is a way to blur the faces that have been automatically identify by the haarcascade face classifier. using the code below, I'm able to detect the faces, crop the image around this face or draw a rectangle on it. image =…
Arnaud Geotribu
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Not able to find faces(face-detection) in django (using python-opencv) project

This block of code (in views.py) is triggered by a URL.No problem in importing cv2.(Same thing tried with virtualenvwrapper shows same result (after adding all required libraries) Camera initializes and .... def caminit(request): cam.open(0) …
Mohit Kumar
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CascadeClassifier in OpenCV generates error

I am trying to develop a simple application to detect faces as well as eyes in a given image: from cv2 import * face_cascade = CascadeClassifier('haarcascade_frontalface_default.xml') eye_cascade = CascadeClassifier('haarcascade_eye.xml') img =…
Namit Juneja
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haar cascade positive example image sizing

Im taking my first steps in making a haar cascade for custom object recognition. Ive spent time getting a fair bit of data and wrote some preprocessing scripts to convert videos to frames. My next step is to crop the object of interes in order to…
YesIndeedy
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OpenCV for Android: failed to load cascade classifier error

This is the first time I use openCV library. I want to use it to detect the eyes. I have used the FdActivity code available in this tutorial: http://romanhosek.cz/android-eye-detection-updated-for-opencv-2-4-6/ The tutorial uses OpenCV 2.4.6, but I…
Dania
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Generating good training data for haar cascades

I am trying to build haar cascades for doing OCR of a specific font; one classifier per character. I can generate tons of training data just by drawing the font onto images. So, the plan is to generate positive training data for each character, and…
Dave
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Haar Training: error (-215)_img.row * _img.cols == vecSize in function

I am trying to train a Haar Cascade to detect hands. I have a vec file of size 1000. I have 40 positive images and 600 negative images. I have tried both dropping my positive images and negative images. When I run the following command I receive the…
dylan7
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Recognising objects in images using HAAR cascade and OpenCV

(This came out a bit long, but it's mostly an hardly hard to understand explanation :) For a project I have I need to recognise objects that, in general form, look like this - Inside a bigger image that contains different shapes, like this one -…
Dan
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Detecting mouth with openCV

I am trying to detect the mouth in an image with openCV, so I am using the following code: #include "face_detection.h" using namespace cv; // Function detectAndDisplay void detectAndDisplay(const std::string& file_name, cv::CascadeClassifier&…
minomic
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Quick way to distinguish similar objects from each by distinct features on one object

I've made a classifier (based on HoG features) that can recognize big vehicles (buses and trucks). But I want to be able to distinguish between buses and trucks, too. This causes problems since both vehicles are big and long. Here's a an example…
user961627
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Hand detection and tracking methods

So, guys, please help me with detecting/tracking hand for user who are sitting at the computer in front of computer(laptop) frontal camera. I've tried these methods: Colour based detection(I've detected the human face by opencv haar cascade face…
timKa
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