How to find each black bar's begin and end row numbers ?
 ... (in vertical direction) A `cv::Mat` binarized image. Thanks I tried like following, `img` is given image in this question. bitwise_not(img,...
View ArticleOpenCV in platform indepentent Gradle project (for Android and Desktop)
I'm using Gluon Mobile plugin in Eclipse to deploy a basic imaging project to Desktop and Android. Gluon Mobile creates a Gradle-based project and uses javafxports. So the idea is write once - run...
View Articlewhy my rectified image is like this
Hello, i have run the stereo calib simple and it have detected 80 pairs with an error equal to 0.5 but it give me a rectified image like this : ...
View ArticleOpenCV: how to set the number of octaves in SIFT?
The number of octaves is a crucial parameter in the SIFT algorithm. However, according to [SIFT documentation](http://docs.opencv.org/trunk/d5/d3c/classcv_1_1xfeatures2d_1_1SIFT.html) in OpenCV you can...
View Articlecan i use Class FaceRecognizer in java native library ?
**i'm first opencv . i used opencv with java programming language and i used java native that opencv give me in folder build . when i need create face recognition application i can not use class about...
View Articledetecting a photograph
Hi all, I'm trying to detect a photograph, maybe up to 3 or 4 at a time. I tried using https://github.com/opencv/opencv/blob/master/samples/cpp/squares.cpp But it works a bit too good (detecting lots...
View ArticleWhat is the best way to detect white blood cells among the red blood cells in...
Please suggest an AI based approach. Thanks.
View ArticleDoing an adaptive thresholding to a grayscale image
I have a png image which is in grayscale 'test.png'. I need to do an adaptive thresholding to this image. I am using opencv2. image = cv2.imread('test_big.png') im = cv2.adaptiveThreshold(image, 255,...
View ArticleDemo Failure : Cannot detect face .Why?
This is the result:  You can see there is no detect rectangle. Where is wrong? Thanks! Below is my codes: import numpy as np import cv2 face_cascade...
View ArticleRemove camera lag in opencv python
i am working on Odroid and running a face detection using open cv python on it. but there is too much lag in the camera. i have tried a lot of things but couldn't remove the lag. please suggest how...
View ArticleHow to construct 3D representation of the scene with more than 2 images?
From a video, I have took three images: i1, i2 and i3. The steps in getting the keypoints in each of the image are: 1. I detect keypoints from i1 and track it with optical flow up until i2. 2. From i2,...
View ArticleUsing Accelerated (OpenVX) with OpenCV 3.2
I noticed in later OpenCV 3.2 changelog that "NVidia corporation has donated ARM optimizations for OpenCV, the Carotene library (https://github.com/opencv/opencv/tree/master/3rdparty/carotene)." Is it...
View ArticleCIE-Lab color value of pixel
Does CIE-Lab value of pixel changes as the object containing the pixel moved in different position in image?
View ArticleHow do I convert 2d matrix in to a grayscale image in java????
double[][] x=new double[800][600]; Now I want to convert x into a grayscale image. I want functionality of matlab function mat2gray. https://in.mathworks.com/help/images/ref/mat2gray.html
View ArticleConverting 2D image to a 3D model
Hello everyone, I am an absolute beginner to the realm of Computer Vision. I realize it is a rather complex subject. However I am not new programming. I discovered this page here:...
View ArticleCanny using separate functions
Hi! I've tried to write Canny edge detector using OpenCV's functions for better understanding. As I can see, my own pipeline has wrong results after non-maximum suppression. cv::GaussianBlur(input,...
View Articletracking movement in a
Hello Forum. Need some help (well a lot really please). I am trying to track movement in an area. Imagine a cat walking across a lawn, it starts at one side and walks across to the other, how do I...
View ArticleObject detection rectangle doesn't cover whole object
Hello everyone, I just started to work with openCV. I decided to use this library to detect an object on image and cut it from them. I trained cascade, unfortunately it doesn't work very well. I tried...
View ArticleDefault color space for frames in video
Hai, I have a video which is having yuv color space and H264 codec. I am using Opencv videocapture function to read a frame. I just want to know whether the frame's mat object is in BGR or YUV color...
View ArticleGeneralized hough transform implementation in Opencv?
From [this](http://stackoverflow.com/questions/25669494/generalized-hough-transform-for-shape-detection) question on stack overflow i know there is no opencv implementation for generalized hough...
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