How to Get Past the Infamous “Insufficient Count of Samples” Error in OpenCV Cascade Training

Many people who have tried OpenCV’s traincascade tool know about a very disturbing error which (at least at the moment) seems to have no good solution, but nevertheless this issue has a solution (even if not convenient) so we need to stick to what we have at hand. My Cascade Trainer GUI app which also uses OpenCV as the underlying framework is also seen to produce this error with many users so I decided to discuss this and share my solution with you all, but please make sure you put your comment below if you’ve got any questions or better suggestions. So, let’s get down to it.

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How to Use OpenCV in Unity (Example Project)

This is a post that many people have requested recently. I’m going to describe how you can use OpenCV in Unity. Of course we’ll be using official OpenCV libraries and not any assets or existing plugins.  For those of you who aren’t familiar with the subject, Unity is a very popular game engine which allows building games, apps and so called experiences with much ease. Unity allows some modified form of JavaScript and also C# for its scripting. In this example project I’ll use C# since that’s the language I’m familiar with but it shouldn’t be hard to adapt this to JavaScript (but you’re gonna do it yourself if needed, sorry) so let’s start.

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How to Use C++/Qt/QML/OpenCV to Write Mobile Applications

I have avoided using QML for long time and always wrote even the most simple applications using Qt Widgets and C++ code but the release of Qt’s Quick Controls 2 and Material Style just made it very irresistible and I had to go for it. Well it didn’t take too long to get a hold of things (for a newcomer) since I had enough programming experience and QML is just too well-structured and easy to learn and use. In this post I’m going to share a project that demonstrates using OpenCV in QML to write beautiful and powerful Android (and other platforms) apps.

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Diffuse Shading in OpenGL Using Qt

This one is taken from one of my favourite books (OpenGL 4.0 Shading Language Cookbook) and the relevant chapter’s title for this tutorial in the book is called “Implementing diffuse, per-vertex shading with a single point light source”. Of course it’s modified to use OpenGL ES in Qt which is more cross-platform and creates less issues with building and running on different operating systems (including Android and iOS)

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Sır aşikar olmaz meğer
Aşkın şarabından eğer
İçsen görürsün gördüğüm
Görmek bu aşuba değer

How to Read Wavefront OBJ Files Using C++/Qt

First of all let’s briefly go through what’s an OBJ File. Here’s a very brief description from Wikipedia: “OBJ (or .OBJ) is a geometry definition file format first developed by Wavefront Technologies for its Advanced Visualizer animation package. The file format is open and has been adopted by other 3D graphics application vendors.” Anyway, I’ll assume that now that since you’re here you already know what an OBJ File is and How and Where to use it.

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How to Show a Toast Message in Qt for Android

If you’re a regular Qt user (like me) and have tried writing Android applications with Qt then you must have come across situations where you’ve needed some very simple capabilities of Android API but it wasn’t present in the Qt library. Displaying a Toast message in Qt for Android is one of those situations. In this post I’m going to describe how to display Toast messages in Qt for Android, and it’s also a very good example of showing how to use JNI (QAndroidJniObject class in Qt, along with Java code) to access Java code from within C++/Qt code.

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Bu iki beyti yine yazmalıyımdır meleğim
Nefesi sözlere aktarmalıyımdır meleğim

Bu işin kürdü de yok, türkü de yok
Arap, acem, hepsi yalandır meleğim

Bu yalanlarla bizi hep ayırırlar
Seni benden, beni senden meleğim

Bizi düşman kılıp asude olurlar
Ama her şey, sonu vardır meleğim

Bu dövüşler, bu savaşlar, bu ölümler
Bir sabah uyandığında bitecektir meleğim

Geriye toz bile kalmaz göreceksin
İzleyen sen olacaksın meleğim

Ne olursak olalım, bu can emanet
Vereni bizleri hep izleyecektir meleğim