MVLab's Activity

Serious problem

2008-12-23T17:28:00.000+08:00

[vnl_quaterion] I made a mistake when coding with quaterion related sections!! the paper format [R X Y Z] vnl coding format [X Y Z R] damn!!! That means I have to compare the version between vnl_quaterion and VW::QUATERION [vnl_matrix_fixed] "fill" member related The source of the problem is that VXL uses explicit instantiation of Templates as opposed to ITK that uses implicit

Few problems u might possibly encounter when deriving class from base class

2008-12-08T15:07:00.000+08:00

1. undefined reference to `vtable for XXXXXXX' vtable means virtual table, all errors about undefined reference to vtable are caused due to virtual function in class!This error might raised due to you declare the virtual functions which are inherited from base class in derived class without implementation. e.g.class Base{ public: Base(); virtual ~Base(); virtual void

Coding Log

2008-09-24T15:44:00.000+08:00

2008 08/27 Prymidal down sampling using Class method performance: ~1.8 ms @ Pentium M 1.73GHz 2008 08/29 Lucas-Kanade Optical Flow tracker ( tracking 1 feature point ) performance: ~0.13 0.7 ms @ Pentium M 1.73GHz 2008 09/11 demo: Drift problem is still not solved. 2008 09/14 when coding matrix operation in the way like matlab, must add library "

Difference between structure of image and frame

2008-09-03T22:29:00.001+08:00

If you have a static image, the pixel sequence of the data structure is top-to-bottle and left-to-right 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Method of processing pixel of image

2008-08-19T17:55:00.001+08:00

1. Include file: #include Pre defination: typedef wxPixelData PixelData;Code example: unsigned char grey = 0;wxBitmap* m_pbmp = new wxBitmap(wxT("name.bmp"), wxBITMAP_TYPE_BMP);PixelData data(*m_pbmp);PixelData::Iterator p(data);p.Offset(data, 0, 0);for ( int y = 0; y < data.GetHeight(); y++ ){ PixelData::Iterator rowStart = p; for ( int x =

Integral table computation

2008-08-06T03:47:00.001+08:00

The raw data: a b c d e f g h i j k

Building Boost C++ lib for MINGW and coding in Code::Blocks

2008-05-18T21:34:00.001+08:00

+ Boost C++ Libraries is one of the most highly regarded and expertly designed C++ library projects in the world. It provides many efficient algorithms to help App developers to improve their program. However, the Boost's official website offers only source files and Build Tools ( Boost JAM ), we must build the suitable Lib according to the compiler ( like GNU GCC Compiler, Borland C++

Configuration of Qt4 in Code::Blocks

2007-11-07T05:08:00.001+08:00

Qt sets the standard for high-performance, cross-platform application development. It includes a C++ class library and tools for cross-platform development and internationalization. Qt is also available to Java programmers through Qt Jambi.This article is NOT a tutorial for programing Qt4 application. It's only made as a note for setting Qt4 in Code::Blocks. Just following the steps below you can

A test for display the cpp code section

2007-11-06T20:15:00.000+08:00

class MyCanvas : public wxPanel{ public: MyCanvas(wxWindow *parent, wxImage img); virtual ~MyCanvas(); wxBitmap* GetBmp(); void OnPaint(wxPaintEvent& event);// void OnCanvasMouseMove(wxMouseEvent& event); protected: wxBitmap* m_bmp; private: DECLARE_EVENT_TABLE()};

int to string code in wxwidgets

2007-09-24T20:01:00.001+08:00

I've been looking for a method that can cast int type to string typeHere are some solution you can useFor console mode by standard C1. int sprintf( char *buffer, const char *format [, argument] ... );ex:char *str;int num = 66;sprintf(str, “%d”, num);printf(”str = %s\n”, str);2. char *_itoa( int value, char *string, int radix );　ex:#include char buffer[20];int i = 1234;_itoa( i, buffer,

Model matching

2007-09-19T13:31:00.000+08:00

You can minimize the 2D distances between the model lines (projectedwith the previous position) and the lines detected in the image.Here are some usefull links.http://svr-www.eng.cam.ac.uk/~gswk2/http://cvlab.epfl.ch/research/augm/augmented.phphttp://mi.eng.cam.ac.uk/~twd20/

Color space conversion for IplImage

2007-06-05T15:16:00.000+08:00

In my application, the color image is captured from my USB webcam.IplImage* frame = cvQueryFrame( capture ); // depth 8 channel 3IplImage* blackwhite = cvCreateImage( cvGetSize(frame), frame->depth, 1 ); //depth 8 channel 1IplImage* differentdepth = cvCreateImage( cvGetSize(frame), IPL_DEPTH_32F, 1); //depth 32 channel 1cvCvtColor(frame, blackwhite, CV_RGB2GRAY); // to convert greyscaleReference

Day record - 2007 May 23

2007-05-23T02:15:00.000+08:00

Finally, I made it. I found out a little GOD DAMN BUG!!That is the type of IplImage image data format is "char".That means if it is bigger than 128, while changed to "int", it will appear as a negative one. In computer vision, the range of each pixel's value is 0 ~ 255. In order to process correctly, each pixel value must be converted from (char*) to (unsigned char*) by cast for IplImage

Day record - 2007 May 15

2007-05-15T16:47:00.000+08:00

convert wxImage to IplImage by "WxImageToIplImage(const wxImage* wx_Image)"Image processing(as the picture show above)convert IplImage to wxImage by "IplImageToWxImage(const IplImage* cv_Image)"Load the wxImage(processed) into my test application and show it./*********************************Convert wxImage to IplImage format.*********************************/IplImage* GUIFrame::WxImageToIplImage

Day record - 2007 May 14

2007-05-14T22:31:00.000+08:00

Build GUI interface for a really poor webcam.Camera selection dialog.Camera resource, format and control menu.A simple callback function to paint 10 by 10(pixels) grid lines on each single frame.callback(IplImage* image)

Installing Code::Blocks and using Nightly Builds

2007-04-27T21:21:00.000+08:00

Here I only show the installation for WinXP. First of all, you must download the Code::Blocks on it's website. It's a good choice to install the Code::Blocks v1.0 RC2 with MinGW compiler. After finishing the installation, go to the Nightly Builds page and choose the newest release page. It looks like below.download the two zip file(*.7z) marked with red box and unzip them.Copy "

A tutorial of WxSmith in Code::Blocks

2007-04-25T21:44:00.000+08:00

http://wiki.codeblocks.org/index.php/WxSmith_Tutorial_%26_Pointers

Compile WxWidgets with Code::Blocks by MinGW

2007-04-25T14:29:00.000+08:00

First step:download the Code::Blocks v1.0 RC2 with MINGW compiler and install it to your systemSecond step:download WxWidgets 2.6.2(might in .7z or setup file format) and then install it to the dictionary C:\wxWidgets-2.6.2, or you can choose the other dictionary.And then we need to compile WxWidgets with Code::Blocks by MINGWThird step:In command prompt, enter the following commandsC:\cd

Errors Logged about CODE::BLOCKS

2007-04-24T17:32:00.000+08:00

I found a powerful C++ IDE called "Code::Blocks" recently. It's a cross platform IDE and the most important thing is "It's FREE and easy to use". In it's website, the author supplies the patch to improve the program and fix the bug every night which is called "Nightly Builds". However, I found there's a little problem after updating the Code::Blocks with the newest Nightly Builds. A warning

Mono SLAM

2007-03-16T11:25:00.000+08:00

Tool box about SLAM ( Simultaneous Localization And Mapping ) http://www.vision.caltech.edu/bouguetj/calib_doc/index.htmlSource Code for FAST Corner detection A Structure and Motion Toolkit in Matlabhttp://homepages.inf.ed.ac.uk/rbf/CVonline/LOCAL_COPIES/TORR1/index.html FAST Corner Detection -- Edward Rostenhttp://mi.eng.cam.ac.uk/~er258/work/fast.html Peter's Functions for Computer

Amazing Robot

2007-02-05T20:33:00.000+08:00

Robot's skateboarding...So Cooooool!!

Wiki of Normal distribution

2007-01-28T21:04:00.000+08:00

Here is a link of Normal Distribution from wikipedia.It will help to understand how to model a pixel with Gaussian Kernel. However, the method is the most useful way for background modeling technology of scene surveillance system to handle non-stationary background scene (e.g, swaying tree branches).

Background Modeling Techniques in Scene Surveillance System

2007-01-17T20:18:00.000+08:00

Pixelwise Median filter:Median filtering is one of the most commonly-used background modeling techniques [1,2,3].The background estimate is denoted to be the median at each pixel location of all the frames in the buffer.The assumption is that the pixel stays in the background for more than half of the frames in the buffer.Therefore, it is applied to several seconds of video to distinguish moving

Baye's Rule & 失落的氫彈

2006-12-02T05:21:00.000+08:00

1966年一月，一架B-52轟炸機在西班牙外海上空與一架加油機相撞，四顆氫彈沈入海底，其中三顆馬上被尋獲，但是第四顆怎麼找都找不到，當時主管核子武器的副國防部長傑克．霍華(Jack．Hayward)親自打電話要求美國海軍深海研究計畫的首席科學家約翰．P．克拉芬博士(John．P．Craven)主持搜尋行動的規畫。當時海軍相關人員大部分都認為不可能找得到該顆氫彈更遑論落入蘇聯手中的機會，但是詹森總統不願意冒任何可能的危險，堅持一定要找到，而唯一對這個任務有信心的人，大概只有克拉芬博士自己一人。條件雖如此惡劣，克拉芬博士於接受任命後首先派出搜尋隊到失事的海域，自己則留在岸上協調搜尋的工作，嘗試推敲出氫彈可能的落點，指引搜尋隊集中搜尋。這真的是所謂大海撈針，他們唯一慶幸的是失事地點附近是大陸棚的一部分，水深約3,000英呎，還在小型的有人深海探測潛艇的作業範圍內，以當年的科技而言，

The Ghostrider Robot

2006-11-28T18:01:00.000+08:00

The Blue Team is developming cutting edge technology to solve difficult problems in robot navigation using inovative approaches.　　The Ghostrider Robot (aka Dexterit), an entrant to the upcoming "Grand Challenge" race sponsored by DARPA, is an autonomous self-balancing robotic motorcycle.　　Science fiction fans may remember the smart bike in Bruce Sterlings 1998 novel Distraction, which he

DIP resources

2006-11-26T01:22:00.000+08:00

http://iria.pku.edu.cn/~jiangm/courses/dip/html/node1.htmlThis website contains lots of knowledge of Digital Image Process, including low-level to high-level technology. Enjoy it!

Understanding of Gaussian noise

2006-11-25T23:29:00.000+08:00

void GrayImage::addGaussianNoise (double mean, double variance){　　cout << " Adding Gaussian noise with mean = " << mean << "and variance = "　　<< variance << " to the image..."　;　　cout.flush();　　srand(1);　　#define unit_random() (1.0*rand()/RAND_MAX)　　#define TWO_PI 6.28318530717958647688　　double temp, u1, u2;　　int ix, iy;　　int num = width*height;　　int tempint;　　u1=0.0;　　for(int i = 0; i < num/2; i

Chroino from Robo-Garage

2006-11-24T05:05:00.001+08:00

Chroino is a small humanoid robot with friendly appearance and sophisticated movements. A newly-developed outer covering that serves also as a frame is called a “monocoque frame” and is made of carbon and plastic, giving Chroino a friendly appearance, light weight and strong frame.Using a new technology named SHIN-Walk, Chroino has the ability to walk more naturally than traditional robots that

Scene Features in Vision-SLAM

2006-11-21T16:08:00.000+08:00

A.J Davison's map-building and localization system is based on discrete features, like the majority of robot navigation systems. Discrete features are easier to represent than continuous objects or regions, and provide unambiguous information for localization. The spatial density of features used can dier depending on how well it is required to represent the world, and individual ones can easily

Robot Senses Damage, Learns to Walk Again

2006-11-21T02:20:00.000+08:00

November 17, 2006—It may look like a metallic starfish, but scientists say this robot might have more in common with a newborn human. The four-legged machine is a prototype "resilient robot" with the ability to detect damage to itself and alter its walking style in response. Josh Bongard, an assistant professor of computer science at the University of Vermont in Burlington, and his colleagues

Announcement

2006-11-13T18:11:00.000+08:00

To be a contributor of this blog,you need to have an account of Google Mail to login.If you have something new to contribute and do not have any Google account, please leave your email (currently use) in comment. I'll invite you to get one.

The salt&Pepper and Gaussian Noise generate Code

2006-11-13T16:28:00.000+08:00

Click "Read more" to read full post.#include #include #include /* ANSI C standard library routines */#include /* ANSI standard string routines */#include #include #include #include "image.h"//****************************************************void GrayImage::addSaltandPepperNoise (double percent){ cout << " Adding " <<

Configuration of static executable program in Borland C++ Builder

2006-11-13T14:01:00.000+08:00

所謂的靜態可執行檔就是一種不需要搭配其他的DLL就可以直接使用的執行檔。很多人常常在問，為何自己做出來的檔案在其他沒有安裝BCB的電腦就不能執行？主要的原因就是在於當你用BCB寫一個程式時，無論這個程式有多簡單。或多或少都會用到一些BCB所提供的動態程式庫。當把執行檔拿到一台沒有安裝BCB的電腦時，因為沒有這些DLL，所以就沒有辦法執行了。要製作一個靜態執行檔其實很簡單，只要簡單的將兩個Project的Option設定好，再重新Compile就可以了。這兩個Option如下：Project->Options->Packages->Runtime packages->Build with runtime packagesProject->Options->Linker->Linking->Use dynamic RTL請確定這兩個選項在你的Project是處於Disable，也就是『