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by HoshiKata
Practical on the fly fast mesh generation from arbitrary points.
by Phil Hopley
Second part in a series on a ROS (Robot Operating System) House Bot
by Ansel Castro
The article shows how to render 3D graphics with C# in .NET using an API Igneel.Graphics.
by Phil Hopley
In this article, we will add AI to an existing ROS (Robot Operating System) House Bot.

Latest Articles

by Edward Sulistijono
Face Recognition with Python Programming Language using Haarcascade
by Markus Koppensteiner
Python code for image-blending based on an image mask
by Dawid Borycki
In this last article of the series, we improve our Python console application for AI-powered social distancing detection.
by Dawid Borycki
In this article, we will use those centers to estimate distances between people and indicate people that are too close.

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OpenCV 

12 Nov 2012 by HoshiKata
Practical on the fly fast mesh generation from arbitrary points.
16 Jan 2019 by Phil Hopley
Second part in a series on a ROS (Robot Operating System) House Bot
20 Jan 2017 by Ansel Castro
The article shows how to render 3D graphics with C# in .NET using an API Igneel.Graphics.
28 Apr 2019 by Phil Hopley
In this article, we will add AI to an existing ROS (Robot Operating System) House Bot.
11 Jun 2020 by Glenn Prince
This article gives you a good starting point for your own object detection projects.
14 Mar 2016 by V.
Case study on how to solve a complex problem by dividing it into smaller problems.
29 Aug 2017 by morzel
OpenCV in .NET for beginners (Emgu CV 3.2, Visual Studio 2017)
8 Jun 2020 by Glenn Prince
In this article, we'll have a look at some of the pretrained models we can use in ImageAI to start detecting people in images.
4 Jun 2020 by Glenn Prince
In this article, we'll set up everything we need to build a hardhat detector with OpenCV.
19 Jun 2015 by Tareq_Gamal
Workaround to run and exchange data between .NET and other platforms
26 Jun 2019 by hemanthk119
Image Classification implementation using Deep Belief Networks and Convolutional Neural Networks in .NET
9 Jun 2020 by Glenn Prince
In this article, we train our own custom model to detect if people are wearing hardhats.
28 Aug 2017 by Ravimal Bandara
A new contrast enhancement algorithm which is fast, simple and powerful by means of boosting and illumination normalization. It was invented accidentally but the performed well in 2 different applications i.e. superficial vein enhancement and blood vessel enhancement in retinal fundus images.
10 Jun 2020 by Glenn Prince
In this article, we begin the process of creating a custom object detection model.
17 Jul 2020 by Sergey L. Gladkiy
In this article, we'll begin the process of how to use a deep neural network to estimate a person's age from an image.
14 Aug 2014 by Android on Intel
For those of you who are interested in developing your own “smart” drone, this article provides easy directions for making an intelligent, autonomous drone using an Android* smartphone, OpenCV*, C++, and Java*.
5 Jun 2020 by Glenn Prince
In this article, we create an object detection model.
25 Apr 2012 by CodeProject, Michael Hopke
Welcome to our continuing series of Code Project interviews in which we talk to developers about their backgrounds, projects, interests and pet peeves. In this installment we talk to Michael Hopke, who helped launch a game and a game development company while still in college.
8 Feb 2015 by tkontos
A WTL based, XML driven shortcut replacement
8 Jul 2013 by pasztorpisti
To be honest I haven't checked out all your code just check out what synchronization primitives are you using in coda_concorr and that is already suspicious. The same is true for your thread funcs that use ugly lockings and antipaterns like "try". You are not using the right synchronization...
22 Jul 2013 by pasztorpisti
Eclipse is an excellent (and my favorite) IDE for java. I wouldn't say the same about it if it comes to C/C++. Instead check out this: http://www.codeblocks.org/[^]. Most of the time I work on windows platform with Visual C++ but when I have to check out a linux bug in crossplatform code I use...
21 Dec 2014 by Vangos Pterneas
How to use Kinect v2 Face basics
30 Apr 2019 by Apriorit Inc, Semyon Boyko
The approach that allows you to make a neural network analyze the current frame while remembering the state of previous frames
29 Oct 2020 by MehreenTahir
In this article we will compare training our models from scratch with more advanced and pre-trained approaches like YOLO.
10 Dec 2020 by Dawid Borycki
In this article, we will use those centers to estimate distances between people and indicate people that are too close.
31 May 2012 by enhzflep
A couple of things spring to mind for such a task.Create a copy of the image and convert to grey-scaleRun an edge-detect filter on it (this will highlight the differences in contrast at feature boundariesI vaguely recall reading of an adaption to the Hough transform that allows circles to be...
26 Jul 2012 by Sergey Alexandrovich Kryukov
Please see the CodeProject articles:Neural Network OCR[^],Creating Optical Character Recognition (OCR) applications using Neural Networks[^],Neural Network Classifier[^],A C# Project in Optical Character Recognition (OCR) Using Chain Code[^],Unicode Optical Character...
15 Jan 2013 by ShubhamSaxena
About how to create your first Emgu CV project
24 Sep 2013 by pi19404
In this article we will look at the application of Mean Shift Tracking for color based tracking.
27 Nov 2013 by User 59241
It is always easier if you post your own code. This is straight out of the documentation:cv::Mat img = cv::imread("lenna.png", 0);if(img.at(y,x) == 255)etchttp://docs.opencv.org/doc/user_guide/ug_mat.html[^]
9 Mar 2014 by SOHAM_GANDHI
How to convert iplimage and Mat to Picture Box in VC++
11 Dec 2014 by Aescleal
You're pushing N values into your vector. For every n
3 Jan 2015 by Richard J. Algarve
Emgu CV - Select ROI (Region of interest) with the mouse in images that do not have the same measurements. This tip was prepared using the framework Emgu CV and C # .NET language.
28 Dec 2015 by Kornfeld Eliyahu Peter
The basic idea of CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) is not to let computers to solve it, so if you can analyse the image by software it is a bad CAPTCHA...And to be honest, the idea of trying to break it smells wrong - don't go that path!!!
30 Aug 2017 by morzel
Detecting a drone - OpenCV in .NET for beginners (Emgu CV 3.2, Visual Studio 2017)
17 Aug 2017 by Intel
Two of our interns in the DPI Community Evangelism group, Isabel Zhang and Milly Xun, have created an interesting IoT/Robotics project over the past two months.
23 Jul 2020 by Sergey L. Gladkiy
In this article we train the CNN for age estimation.
11 Dec 2020 by Dawid Borycki
In this last article of the series, we improve our Python console application for AI-powered social distancing detection.
5 Dec 2023 by Richard MacCutchan
See OpenCV: Feature Detection and Description[^]
19 Mar 2011 by Du Sijun
Latest update! Problem solved!This happen to be one of OpenCV 2.2′s bugIn $(OpenCV Folder)\modules\highgui\src\precomp.hpp around line 60+ replace following#if !defined WIN32 && !defined _WIN32#include “cvconfig.h”#elsevoid FillBitmapInfo( BITMAPINFO* bmi, int width, int...
26 Feb 2012 by BupeChombaDerrick
Try checking out this linkTrackEye : Real-Time Tracking Of Human Eyes Using a Webcam[^]I understand what you are trying to do.But instead of detecting rapid eye blinks why not detect whether one closes a right or left eye instead. With this suggestion, you need to detect faces first, see...
1 Apr 2012 by Richard MacCutchan
Nobody is going to do your work for you, and if this is supposed to be complete for May, then you have left it rather late to complete. There are lots of articles available on the internet via Google[^] but, as I advised another poster today, it is no good downloading code from the internet and...
19 Apr 2012 by Sergey Alexandrovich Kryukov
What you need is called OCR — Optical Character Recognition. Please see:http://en.wikipedia.org/wiki/Optical_character_recognition[^].For starters on OCR with OpenCV, please see this nice and short article:http://blog.damiles.com/2008/11/basic-ocr-in-opencv/[^].You can find...
1 Jun 2012 by nv3
This requires some more preprocessing steps. Not easy to describe in a quick answer. it is more like a full image processing project. What you have to do in my opinion is: * apply a pepper and salt filter to get rid of the structure (median filter) * apply a 2D edge finder (Canny...
14 Jul 2012 by El_Codero
Hi,please have a look at this CP Articles, they should teach you how it works, it's a huge topic:A C# Project in Optical Character Recognition (OCR) Using Chain Code[^]Contour Analysis for Image Recognition in C#[^]Unicode Optical Character Recognition[^]Best Regards
20 Mar 2013 by nv3
The problems was actually OP was uncertain on how to extract the line images from the main image after having calculated the position of the line gaps. As a result of the discussion in the comment section (see above) the case could be resolved.
26 Mar 2013 by Zoltán Zörgő
As SA Sergey mentioned, it seems not trivial at all. Finding fingernails is one task, detecting fungus is an other. I have only suggestions for the first one. I suppose you can use Haar Cascade to find fingernails - you can train OpenCV cascade. Choosing OpenCV (more preciesely EmguCV) is a...
29 Apr 2013 by Jake Drew
Image thinning using R.
29 May 2013 by Sergey Alexandrovich Kryukov
Please see my comment to the question. Imagine all your calculations are correct, which is pretty likely. It could be just withing the accuracy of the method. But then, if you re-sample some image, it is not exactly the same image. Think of this in this way: you image itself isexpressed in pixel...
2 Sep 2013 by PeterHall
Hi Just a quick question, i've got this bit of code (below) and this is in my main form, it defines a glyph or symbol thats used in augmented reality, problem is that each symbol is different and say if i had 50 of these then the sourcecode would be quite big, and if i needed to add new symbols...
2 Sep 2013 by Keith Barrow
In this case I'd question the need to store these in a database: 7x7bytes x 50 glyphs = 2450 bytes ~ 2.5kB, which isn't very much. Also you only seem to have "1"s in your matrix, you could use booleans and convert, this would save space. Including a database on the target device will swamp any...
20 Sep 2013 by CPallini
The documentation[^] (concisely) explains it all. For instance, it states that cvCreateMat is a just shortcut (or a 'convenience function') for the sequenceCvMat* mat = cvCreateMatHeader(rows, cols, type);cvCreateData(mat);
26 Sep 2013 by User 59241
This is a big subject but very easy to research using Google. Handwritten makes it quite difficultUsing Hough lines in printed text is a common approach which may not work here.This paper is somewhat related to your problem.http://www.sersc.org/journals/IJAST/vol48/5.pdf[^]Some...
26 Sep 2013 by enhzflep
Quite some time ago, I ran across the following article: How to deskew an image[^]The code as presented is in VB.NET, though porting it to c++ is a fairly quick task. There's roughly 350 lines of code for the body of the 'deskewing' (rotation angle detection) class.Since there are a huge...
15 Oct 2013 by Sergey Alexandrovich Kryukov
Agree with nv3, this is not a subject for a Quick Answer. This task will need some research. As you say it should not protect against counterfeit bills, it makes the solution of the problem quite realistic.I would suggest to try out the following route:First, you can to create bitmaps of...
8 Nov 2013 by Sergey Alexandrovich Kryukov
You don't need this function from some API. Why do you think that someone will develop function for all partial cases from elementary geometry. I would not make any sense.I answered to the question on this topic here: C++ how make an Array of recursive Objects like 8-branches...
26 Nov 2013 by Domus1919
I want to ask a question: I'm using OpenCV 2.4 and I have to check the value (time by time) of a pixel addressed (X,Y) in a binary thresholded OpenCV Mat image.I have to check if the pixel at the X,Y that I want to verify (and pass to a fuction) if is black or white (0 or 255)...what is the...
4 Apr 2014 by SoMad
I think you are looking for this: OpenCV - How to Use Background Subtraction Methods[^]Take a look at this answer on SO in case you have a problem similar to the poster: http://stackoverflow.com/questions/19221877/opencv-how-to-use-createbackgroundsubtractormog[^]Soren Madsen
4 May 2014 by Legor
You can't just directly calculate the distance between two pixels in real world units. You will need some more information which may be obtained in several ways: - Considering the person is passing the camera almost horizontal (not walking away from or up to the camera) you may use the...
28 Jun 2014 by nv3
First of all, why do you post hundreds lines of code in a quick question. Do your really expect people to read your entire program?The error message obviously comes from the SVM.train call in your svm function. So that would have been all you should have posted.Now, if you read the error...
12 Sep 2014 by Sergey Alexandrovich Kryukov
Please read Open CV documentation:http://docs.opencv.org/modules/core/doc/old_basic_structures.html[^],http://docs.opencv.org[^].The question is not very productive. It's pretty apparent that you are asking on the code which you did not write by yourself. Why trying to dig in it if you...
10 Dec 2014 by matthias-hahn
The Intel® Internet of Things (IoT) Developer Kit (dev kit) is a complete solution for creating and testing applications targeted for Intel® IoT platforms like the Intel® Galileo board.
20 Feb 2015 by Sergey Alexandrovich Kryukov
Epigraph:The steering mechanism of the tank is used for turning left, right, and other directions.:-)Here is what I would advise: don't do background subtraction, and even less try to get the object outline. Do something, in a way, opposite: blob...
28 May 2015 by KarstenK
It is a linker problem, which means that the declared function isnt available for the linking stage. You must inlcude the implementatiion (file) of this function or add the lib to linked libraries. (Possible a namespace issue?)
23 May 2016 by Dave Kreskowiak
If the videos are already encrypted, I doubt you're going to get any compression at all, if not very little.For the best result, the video would have to be compressed first, then encrypted.
27 Nov 2016 by Member 12761317
I'm using IP webcam android app(It converts mobile camera into IP web camera). I'm running below code in Visual Studio 2015 with OpenCV 3.1. VideoCapture cap; Mat img; cap.open("http://192.168.0.101:8080/video?x.mjpeg"); while(waitKey(33)!=27) { try{ ...
7 Mar 2017 by OriginalGriff
The whole of idea of "i need a new code which is not in existance" means one of three things:1) You want something you can hand in as your own work.2) You want something written specifically for you.Or3) You want something that doesn't exist yet.So:1) We do not do your homework: it...
18 Aug 2017 by Intel
This paper addresses how the Smart Video (SV) system architecture is increasing in complexity and evolving into new industries and use cases.
25 Jan 2018 by Intel
This tutorial will walk you through the basics of using the Deep Learning Deployment Toolkit's Inference Engine (included in the Intel® Computer Vision SDK).
26 Oct 2018 by Dave Kreskowiak
First, you're going to have to learn how to use OpenCV. We can't tell you everything you're going to need to know in a few forum posts. You can start here[^]. Next, you're going to have to dig into object recognition. Be warned, this is far from a trivial tasks. DO NOT EXPECT TO DETECT...
13 Nov 2018 by lessthanoptimal
This article demonstrates how BoofCV greatly simplifies working with cameras on Android.
14 Nov 2012 by Du Sijun
Hi, I can not capture image from my webcam using following OpenCV code.The code can show images from a local AVI file or a video device. It works fine on a "test.avi" file.When I make use my default webcam(CvCapture* capture =cvCreateCameraCapture(0)), the program can detected the...
25 Jan 2012 by Tarakeshwar Reddy
It is your project and you would have to do it. If time is not enough, go to your prof and ask an extension of time. If you do not know the technology, I would suggest taking something simpler which you understand and implement. Taking a complex project will not help you get good grades. A...
26 Feb 2012 by BupeChombaDerrick
Trying checking out this articlehttp://www.eecs.umich.edu/~silvio/teaching/EECS598/papers/leibe-dynamic3dscene-cvpr07.pdf[^]But be specific, what you are trying to do is not even a well understood problem, so you must do most of the research yourself.
14 Mar 2012 by nv3
Here are some suggestions about how you might tackle the problem. First of all you need to decide by which criteria you want to detect a finger in the image. This decision depends mostly on the physical details of your setup. For example: - The person might wear a thimble that is...
1 Apr 2012 by Pranit Kothari
I think you should read this[^]
2 Apr 2012 by zarunz
We want to extract an adaptive background from a video sequence. Can you please suggest an effective and simple method.
14 Apr 2012 by BupeChombaDerrick
The code below is a slight modification of code from openCv 2.3 tutorial.You can use it to find image A in Image B. It uses SURF (Speeded Up Robust Features)http://www.vision.ee.ethz.ch/~surf/eccv06.pdf[^]FLANN (Fast Library for Approximate Nearest Neighbors)...
26 Apr 2012 by Lakamraju Raghuram
You should have read their documentation or atleast googled.Check out herehttp://www.cs.iit.edu/~agam/cs512/lect-notes/opencv-intro/opencv-intro.html[^]
29 Apr 2012 by jk chan
you can use Hough Transform to detect rectangles. see...
23 May 2012 by Prosan
you can save image in database of sql as Varbinary(Max) datatype and saving image in database. First save image at particular path than readallbyte from this image and save these byte in your database table as describe in this code:-using System.IO;using System.Data.Common;using...
26 May 2012 by BupeChombaDerrick
Color processing or color vision may sound simple but i suggest you think again. With some inspiration from human visual system. http://en.wikipedia.org/wiki/Color_vision[^]It starts out as an opponent process http://en.wikipedia.org/wiki/Opponent_process[^]In which color channels R,G,B...
26 May 2012 by Member 9033457
I'm planning on doing an project related to Augmented reality, which will be focusing on developing a calculator for the primary children. Therefore i will be using a set of cards(15) which will have numbers from 0-9 and the 4 operands(adding, subtraction , division and multiplication) together...
29 May 2012 by nv3
Beware, thinning is not equal to erosion! You find a good article about thinning here: Thinning Algorithm[^]
6 Jun 2012 by arthur.rafa10
hi does anyone have an example of invariant moments implemented with OpenCV? preferably in C # or C + +. please someone help me? Thank you!
14 Jul 2012 by R. Giskard Reventlov
Start here[^].
14 Jul 2012 by Sandeep Mewara
How about going through this article: Multiple face detection and recognition in real time[^]
15 Sep 2012 by Mehdi Gholam
It's very hard to help you with the information you provided.Having said that, debug your app and look at the inner exception, it is possible that some assemblies can not be found or you have licensing problems.
17 Sep 2012 by Sergey Alexandrovich Kryukov
Look at the documentation of EMGU you have: it should tell you the target version of .NET it's using. Find out what .NET version do you need and install it. Do you use Visual Studio? What version? If you have VS 2005, you can develop only the applications targeted to .NET v.2.0, VS 2008 covers...
25 Sep 2012 by manoranjan
If you want to capture video (from your webcam) using OpenCV, check out the following sample at OpenCV wiki: http://opencv.willowgarage.com/wiki/CameraCapture[^]If you want to use Win SDK, use either Video for Windows (WfW) or DirectShow. WfW provides capCreateCaptureWindow() API to...
7 Nov 2012 by Richard MacCutchan
You cannot merge DLLs into an executable, they are stand-alone loadable modules. You need to copy them with your executable to the other computer. you can do this manually or by creating a setup program. You did not give details of the problems you had trying to rebuild as static libraries so we...
5 Jan 2013 by Dilan Shaminda
Hi,i am an undergraduate student and our group hope to do a research on sign language Recognition area.In there we have a problem of breaking down a sentence into words which is shown by a deaf student.ex: He goes to school we want to track above sentence word by word.but the problem...
20 Jan 2013 by Grasshopper.iics
Detecting Eye is moreover a template matching problem which can be done through cross correlation of a template image and main image.Here is a simple method in OpenCV C for detecting eye.locate_eye(IplImage* img, IplImage* tpl, CvRect* window, CvRect*...
19 Mar 2013 by Matthew Faithfull
By the look of it that one doesn't work so well. Perhaps this one[^] or one of the others thrown up by a Google search is better.
20 Mar 2013 by Legor
An implementation of the Kalman-Filter is available in openCV as well. Since you allready use openCV you should start with their implementaion of this too.See the documentation...
8 Apr 2013 by Sergey Alexandrovich Kryukov
I think that your circles you observe on the finger tip are all nested in each other. And I think that you want to have only the outer nested circle, remove all inner ones. If this so, you can develop a simple algorithm: find a convex hull of each "circle". Say, collect all hull points and...
1 May 2013 by YDaoust
If you detected all five tips and know the direction of the hand, it suffices to realign the hand in the vertical direction. You can sort the tips left to right; thumb is the lowest of leftmost and rightmost.
25 May 2013 by Santhosh G_
for(int i=0;i
29 May 2013 by David Jhones
it is mentioned as Hu-moments are invariant from scale, rotation and orientation. But when i compared the Hu-moments by using same image with different sizes and angles, i got slightly different values.i get image with 100,75(height,width) at first time and then same image with...