St. Paul’s hall in sunset.

St. Paul’s hall, taken on my way home.

The sunset scence puts more mysteries on the hall taper.

On my way home, the St. Paul’s hall in Huddersfield.

Happy lunar new year of tiger!!!

Can you imagine the sky rains hamburgs? Here it is, the “cloudy with a chance of meatballs” which presents a vivid story about a young crazy scientist invents a rocket which is able to turn water into food. Be careful of raining meatballs or steaks.

At one time I was asked by Lesley how many films had i watched that, i could tell stories predictably, here my answer is just as average or, even less. Then i know, there needs some strong explanations to address such confusion. The reasons include being familiar to history and its sense of worth, the trail of screenwriters’ thoughts and some knowledge of commercial movie’s publication. No complicated logic is needed.

Clues in movies are subtle and invisible but not undiscovered, they just lay behind scenes which are quite possible to be ignored by audiences. Yes you can say my observation is sharp. However that is not the full answer, the other is thinking. I feel like watching movies very much not because i am presented fun, rather, i feel movies extend my life from single person to multiple dimensions, e.g. being bad guys, falling into love with someone and kind of revenge. I am able to continually experience all kinds of lives unless i quit watching movies. And my life becomes longer in another sense. Besides these experiences present me new feelings, they inspired my mind and equip my insights.

I wish i just made a clear explanation. What extra i’d like to mention here is, movies are movies, and life is still life.

The dramatic contrast between big cities and small villages in China has been witnessed all along my way home. When i was in Shanghai, its modern architectures impressed me very much though i do not feel like them as expected. However these high and low buildings can not be found any warmness but naked commercial competition atmosphere. They appear brand new but no stories behind, neither tenderness as i can find in vast villages in UK. My question is, would that be an ideal place as home for residence in the future ?

Conclusively there are two ways of objects recognition, which are

• combining simple shapes’ recognition to detect complicated objects;
• using pre-trained data to match objects if they are as set.

The ways we used to detect circles and lines by openCV belong to the first category, and training needed recognition ways such as faces detection and hands detection belong to the second category. Recognition can be quite stable after good data training, but it may not recognize other features without pre-defined, so does the rules of faces detection with openCV.

But if recognition is used to design other applications such as objects controlling or multi-touch demonstrations, it could not be better choice adopting training way to set up recognition functionalities. As the picture shown above, i abstract the recognition part from ARtoolkit which is a popular open source library in internet. The training and recognition test results shows that  it can recognize nearly all the patterns pre-trained.

Quite much work has been doing to improve accuracy of pattern recognition, to enable computer applications being sufficiently intelligent facing this dynamic world. ARtoolkit is one of them. By training computers to recognize patterns as shown above, i have opportunities to shift my attention from recognition to applications, which means, representation forms of recognition affect interaction.

By extracting recognition codes from ARtoolkit, it seems easier to train a computer to recognize patterns like letters and other graphics, and its recognizing results seem pretty good. Based on that, creating appropriate applications become urgent.

The reason of that shortage is due to the lacking of appropriate algorithms. In AS3 objects can not be respectively recognized through colors or shapes before. Fortunately through combination of some kinds of image processing functions, we could still be able to find out the exact way of representing objects under webcam, just as processed images shown below.

This progress provides AS3 more potential to build up interactive prototypes through webcam and normal surfaces with kind of semantic objects laid on. Thus the AS3’s abilities of building up flexible interfaces may be well used in afterward works.

Snowed again from andol on Vimeo.

Surprisingly it snowed again in the second day of new 2010.

While i was watching 3D ‘avatar’ in cinema, i never had such strong feelings that i hope human beings failed, in all their invasive missions on purpose. Or after we failed the earth, we would get revenge as well.

Merry Christmas!

One very interesting aspect of human-computer interaction is methodologies and their effectiveness. There is a view bore in my mind that until interaction became invisibly natural, then interaction did its job. Comparing to thousand years’ history of human lives, computer interaction faces its challenge to integrate itself into natural lives.

We use object recognition to simulate original daily domestic interaction like reading mails and leaving notes. Once computers can recognize specific objects as different meanings relating to its huge stored information, we believe that would be a further step towards natural and efficient interaction.

From shallow to deep MFC.pdf

VC++.pdf

While i was starting MFC in visual studio 2008, i got a fatal error in debugging as below:

Your version of the windows SDK is earlier than 6.0. Try setting the ‘WINVER’ and ‘_win32_winnt’ definitions in your project to less than 0×0600.


I tried several ways to fix that issue while nothing happened, also i investigated the documents in internet by Google neither any helpful information was provided. There indeed existed a solution which was as blew:

stdafx.h- add these codes in the header
#ifndef WINVER                  // Specifies that the minimum required platform is Windows Vista.
#define WINVER 0×0500          // Win2k
#ifndef _WIN32_WINNT            // Specifies that the minimum required platform is Windows Vista.
#define _WIN32_WINNT 0×0500    // Win2k

While that solution did not make any differences. And i tried another way- to download the Windows Platform SDK and installed it, and the most important, update the including library files to at least version 6, then try it again, everything was done.

China’s 60th Anniversary national day – timelapse and slow motion – 7D and 5DmkII from Dan Chung on Vimeo.

This is a video clip which was made by Guardian.co.uk. Comparing with CCTV’s video recording, this video has a more interesting lens to watch the parade.

Just on my way home, i saw a squirrel looking for food in the litter. When he saw me he just ran away to the wood near the litter.

Today is Confucius’ birthday and 52 contries’ google logos have changed to Confucius’ birthday celebration. Never saw that before, it is exciting. The Chinese words in the logo mean that ‘a friend comes from far away, itn’t that a very happly thing?’ Yes, it is.

This is a picture i took on my way home while passing the woods near the civic center, the sunshine, and the trees made people so peaceful.

This is a screenshot of demonstration hands detection using the code hsv.cpp. Comparing with the old version within black background and green contours lines, this version actually is based on that. Besides, two functions are added in this new version: using rectangle to locate the hands location, and using eslipe to illustrate the angle of hands motion.

hsv.cpp source code

Related post may interest you

Hand gesture detection and recognition using openCV

Some posts with prototype codes are occasionally requested to share the relevant codes. Due to this, i make a code collection in this post which could be convenient for all the readers. But please note that some codes still need additional image files or haar files that you should pay attention to.

haarFaceDetect
If you can not download the source code file, please refer to below
http://www.andol.info/download/haarFaceDetect.cpp

This is a prototype designed to test face detection using haar training algrithms. Needs image with faces and relevant haar trained xml file.

hsv
If you can not download the sourse code file, please refer to here below
http://www.andol.info/download/hsv.cpp
This is a prototype designed to detect hands ( not hands gesture ) in the dynamic motion images from web-cam. It uses color in a specific range to detect the hands, and then filters all the noises out to get the biggest contours of hands. Several backgrounds are tested by this codes.

HoughCircle
If you can not download the source code file, please refer to here below:
http://www.andol.info/download/HoughCircle.cpp
Static circle objects in the image are quite simple to grab. However, when it comes to combining recognition containing squares and circles, i have to admit that squares are easier to detect.

Andol in Cambridge from andol on Vimeo.

This is a short video of Cambridge tour. Admittedly, Cambridge is of a great place to dwelling.

Due to the previous domain “iandol.com” has been suspended in 13/07/2009, some of contens probably would not work perfectly. I am sorry to that and i will fix it soon.
–
Another bad news, i am indeed sorry that when i was trying to fix the problems above i replace all the post contents by mistake. Fortunately i recovered the data from a backup of 11/06/2009 although some posts got lost.

Thanks for your patient.

BBC has launched a new video channel in which some live webcams are capturing videoes of nature anamals, like swallow, greenfinch and kestrel all the lovely small animals. Through the online video player, we can watch the little birds waiting for being feed and playing in their nest.

This is the little swallows waiting for their parents back feeding them.

And, these are little greenfinchs, just playing in their nest happily.

The live broadcast is always online, but, i am not sure the users out of UK could be able to watch it, the address is here: http://www.bbc.co.uk/springwatch/webcams/#2

Recently, it is being applied to consumer electronic products because companies consider it an important key to their success.

However, there is a difference in the concept of usability between the two applications. Unlike the software user interfaces, the image/impression felt by the users are as important as the performance for a consumer electronic product to be successful. ”

Sunny day, i, with my housemate went out for cycling along the huddersfield canal. It was planed a fantastic routine, unfortunately, the mile reader didn’t work firstly, closely after that, on a short up going bridge, another bicycle’s bearing was not able to afford the weight and it was brocken.

So, we have to change the plan from cycling to walking home. I took some photographs along the cycling way, have a look.

FOR THE MEMORY OF PR RECOVERY

While changing the domain name from andol.info to andol.info, i lost all the page rank datas which was reset to zero. After nearly 2 months’ waiting, finally, the page rank starts to recover. It is back !

As the post ‘10 videoes show some interesting AR applications‘ showed, integrating augmented reality technologies into interactive scenerial building is increasingly enhancing the experiences of interaction, both in the side of realastic world objects recognition and virtual applications.

These 2 pictures showed above are a demonstration of AR technology application with ARToolKit. Especially, i changed the default pattern for recognition and printed my own name on the card instead. After i trained the codes to recognize the new pattern, obviously, i got the satisfactory consequence. The codes recognized that new pattern rapidly and accurately, as well as using openGL to create practical coordinates and virtual 3D cube.

Although this isn’t the newest technology today, it indeed explored a new path to archive another advanced interaction method.

ARToolKit is a software library for building Augmented Reality (AR) applications. These are applications that involve the overlay of virtual imagery on the real world. For example, in the image to the right a three-dimensional virtual character appears standing on a real card. It can be seen by the user in the head set display they are wearing. When the user moves the card, the virtual character moves with it and appears attached to the real object.

— artoolkit programe

And the video show blow, is an extension of artoolkit, worth having a look.

During the past days, i was trying to get the computer recognizing blue and red colors to archive my prototype application. I tested two methods to distinguish the colors recognition effects, that were value-fixed approach and value-dynamic approach. 

What i was doing is to build a simple, flexible and adaptable intellegent colors recognition prototype which could work under varities of spatial environments. First, a fixed value of color was set. Any colors match this value would be recognized as specific one. It is simple and easy, although it is dependentable on the environment light. ( if the environment is controlable, this method would be good one. ) Second approach is that, i devided the picture into 3 channels which are H, S, and V. And then, from H ( Hue), i defined a range of color as one color and other ranges for another. This experiment looks not so difficult and more robust that previous one, however, there’s still one thing which should be cautious: light temperature. Light tempreature changes, color’s hue exceeds.

So, before there invents more advantaged devices, recognizing which colors from which colors is relatively limited.

Well, after watching this clip, i have to admit that augmented reality has the potential of combining the advantages of both well-spatial virtual reality and spatial augmented reality. And, i don’t konw if you have noticed that, actually, the demonstration in the video was made by Actionscript which included pattern recognition and 3D display rendering.

[ For more details, please go to slashgear ]

[Pictures from BBC.co.uk, all rights reserved by original authors]

This is the 2nd part of usability evaluation for go.taobao.com. According to the 1st part evaluation, we found some of unfluent to browse the pictures which is probably due to the networking speed. So, in this review, networking was test 5 times destributed in different times in the day and night.

One random search word was selected on the page which looks quite hot. And, onece the first page was ready, regular click started at the rate of 1 click one second. Looks quite smooth at the first beginning~

Oops, looks something happened accidently, the picture displaying was sucked although the small thumbnails were still working.

Ok, waiting would be the only thing to do…

Getting into the picture detail entry, new window, detailed page and … oops, a small thumb’s missing.

Finally, the pictures caught up with my brouwsing. Wait… what is this, motel ? i found it when i was searching skirt ? Cool~

Again, similar lagging behind things happened, fortunately, i have understood it now.

So, the review conclusions:

1)  Precise picture matching, need be improved ( at least dont mistook motel to women’s dress, ;] ).

2) It is better to improve the rapidly picture browsing, don’t show sucking status in the front of users.

3) Small thumbnails are much faster to be loaded than big ones, why not fill the page with numrous of small pictures ( clear enough ) which would indicate bloody number of pictures.

4) The most important one, fliping from right to left seems not the perfectly effecient way to display information like those thousands of handreds pictures. If it flips fast, it looks blur and the users can not see the contents.

Morning by Krzysztof Browko

Goðafoss by Ragnheidur Arngrimsdottir

Morning impression by Przemyslaw Wielicki

Central Balkan by Vladimir666

Flowing Water & Ice Formations by Doug Roane

Morning Sun by Norbert Maier

Planet Earth by steler

A Reflective Morning by John Parminter

Gold Fields by Janusz Wanczyk

Sea by jtangen

Morning line by Janusz Wanczyk

Mountain Waves by Alan Czekierda

Dream about a green valley by Janusz Wanczyk

Two valley view by Bergljot

Autumn curve by Janusz Wanczyk

Lovely Old Lane by Northman

Morning valley by Janusz Wanczyk

Elf’s Land by Alexander Maslarski

Thin Ice by Doug Roane

In the mist’s sea by Janusz Wanczyk

The Sky Goes All the Way Home by Mark Broughton

Strolling on the Dolomites by Robert Strahinjic

Glacier Formation by Axel Gimenez

Sea by Boots

Pangong Tso by Prateek Dubey

The Other Side by Stefan Bingham

Seljalandsfoss by Henrik Spranz

[From smashingapps.com, all rights reserved by original authors]

There is a comment plugin for wordpress which is called ‘Wordpress Thread Comment‘  which was develped by ‘Author: 偶爱偶家’.

This Plugin is an enhancement for Wordpress’s comment function. It enables users to reply on a exist comment, and the discussion will be displayed threaded or nested.

But, i found a new way to get ‘reply comments’ function working without plugins, it is very simple:

First, check the wordpress version, i hope it would be 2.7.

Second, download ‘comments.php’ from wordpress 2.7’s default thems folder.

Last, replace the new ‘comments.php’ file as the older one and check the wordpress admin’s settings/discuss to enable multi thread comment.

Well, get some CSS style to control the display and start to enjoy it !

This showcase will focus mostly on the layout and organization schemes. Below are about 40 different typographic layouts used in different fields of print such as brochure design, editorial design, and poster design.

Effektive CV/Poster Mailer

Spit Kingdom

Sheridan & Co.

Avant Garde Gothic Typeface Booklet

Akimoto Typeface

NTU Art & Design Prospectus

BABE

Rizzo + Gobart

Mise au point

UsineSonore

Bionic Systems

National Geographic

Colorcubic

Kiosk 37

ALPHA_TXT

Posters by Official Classic

Poster

Stel Christian Cambas Poster

Typography Poster

Beck 8-Bit Variations

Children of the idiom

Commune

Aesthetic Mathematics

What’s the World…

Oscar_Wilde_Retrospective

Play With Colors

Posters by Pablo Alfieri

More Posters by Pablo Alfieri

99 Dingbats

No Lemon Daydream Magazine

Lazydog

Real Dutch Design Books

Macro Micro

Marius Martinussen

DADA Design

Berlin Cafe Posters

[From smashingmagazine.com, all rights reserved by original authors.]

After several weeks’ hard working, finally, the memory leaking problem is fixed. 

In the last post which listed nearly all kinds of variaties declare and delete methods, here i add several tips for memory check while it is leaking:

1) int, double, float … : these kinds of variaties don’t matter so much;

2) IplImage* : this really matters, especially when cvCloneImage is conducted, if the destination variaty was not cleared, the memory would fly up.

3) CvMemStorage: be careful, to delete this data you have to use not ‘cvReleaseData’ but ‘cvReleaseMemStorage’, one declaration, one delete operation.

The main page is quite a little dark with simple search engine like style to lead user easily finding the entance. Some hot search words and pictures, on the left top corner, a even more simpler interface style switch button is there, but not so clear what it is used for until click it. 

Typing some words and click search, there comes results page. Looks the images are quite huge and slow to load, during the tests,  i tried several times to reload to stop page getting down, but at last i gave up to go back. Probably, the web speed would be the first problem.

Finally i saw the pictures, fantastic indeed, except bit of slow speed.

Browsing the page by click or wheel scrolling, either is good to use, nice work.

Oops, got down again. I wonder, why does Taobao sacrify so much waiting time to show such couple of pictures, patient challengable ? It would be nightmare under china’s web speed environments. 

So, i designed an illustration below to compare with the original one: getting smaller pictures which can be enlarged when mouse is over.

Here is just the first sight review, whether it is good to use or not, how easy to use and what exactly the interaction effectiveness it is, all those will come up soon. 

I have a similar problem. On page.php, after the loop I’m using get_posts to grab and display some Posts that are related to the current Page.

Everything is fine except that I’m getting full content without the more link. Does the more quicktag not work with get_posts on page.php?

Here is the solution: 

the “more…” does NOT work on Pages by default – a Page displays just one single entry, so no need for it: there is no “multi-Page” view in WP.

According to some older posts in this forum that you could find by searching – this should address the issue:
<?php $more = 0; ?> if placed before the query.

After much experimentation, here is what I’ve learned:

The more quicktag does not seem to work with get_posts() outside the loop even when using $more = 0; or a custom template instead of page.php.

The more quicktag will work with query_posts() outside the loop if you set $more = 0; even if you use page.php.

A note for people switching functions. Use category= with get_posts(). Use cat= with query_posts().

Next challenge: get tags working on my related posts displayed below a page’s content.

Here’s my query for posterity:

<?php if (isset ($relatedcat)) {
// related cat set in custom field
 $query= 'numberposts=99&cat='.
$relatedcat.'&orderby=date&order=ASC';
 query_posts($query); // run the query
 global $more; $more = 0; // allow more quicktag
 while (have_posts()) : the_post(); // the loop
 setup_postdata($post);
?>
<div class="post" >

It can be a daunting task to hunt exactly where memory needs to be released. So I’ve compiled this short list of places where you should look out for memory leaks.

Create it, then Release it

If you create something, make sure you release it before “returning”. This is probably the very first thing you should check when fixing memory leak problems with OpenCV. For example, if you do a cvCreateImage, make sure you do a cvReleaseImage. There are many things you can create. Here are some functions that “create” and their corresponding “release” functions

One warning though: If you create something and want to return it, don’t release it. Lets say a function that creates a checkerboard image and returns it. If you release the image before returning it, you’re freeing all memory that stores the image data. And when you try accessing memory that isn’t yours, you get a crash.

Release returned structures

This is the second thing you should check for. Often, once you return a structure (say, an image).. you forget about it.

Multiple Memory Allocations

This is the third thing you should check for: Allocating memory, and then changing the pointer itself. Here’s some example code:

IplImage* image = cvCreateImage(whatever);
image = CreateCheckerBoard(whatever);
…
cvReleaseImage(&image);

This function creates a memory leak. First, you allocate some memory for image. Then, you call the function CreateCheckerBoard. This function itself creates new memory. And image now points to this new memory. The memory created in the first step is lost forever. No variable points to it. A memory leak. To fix this, you need to modify the code like this:

IplImage* image = NULL;
image = CreateCheckerBoard(whatever);
…
cvReleaseImage(&image);

If you return a sequence, release its storage

There are many instances where you use the CvSeq data structure. And often you might want to return this structure for further use. If you release its storage (a CvMemStorage structure) within the function itself, you’d free the memory where the sequence is stored. And then you’d try and access it in the calling function. Again, crash.

A temporary fix would be to just erasing the cvReleaseMemStorage statement… but that would mean lots of memory.
To fix this, you don’t release the memory in the function itself. You release it in the calling function like this:

cvReleaseMemStorage(&thesequence->storage);

storage is a member of the CvMemStorage structure that always points to the memory where its stored.

Again, this is just an example. There are more structures where a similar situation could arise.

Dependence on other structures

I quite recently discovered this memory leak. To explain this, I’ll use an example: Lets say you find out the contours of an image. OpenCV would return a “linked list” type structure calledCvSeq. You decide to access the third element of this linked list. OpenCV returns a pointer to the third element. All going great till this moment.

Now you decide to save all the points of this contour (the third element) in a data structure of your own. Since this is an array of points, you do something like:

mystructure->points = thirdcontour->points;

You set the pointer to equal to the thirdcontour. This is the bug. If you release the storage of the sequence (which you should), mystructure has a bad pointer. To fix this, allocate new memory to mystructure->points and then copy contents ofthirdcontour->points… something like this:

mystructure->points = (CvPoint*)malloc(sizeof(CvPoint) * thirdcontour->total);
memcpy(mystructure->points,thirdcontour->points,sizeof(CvPoint)*thirdcontour->total);

This creates new memory for your structure and then copies each element there. Once you’ve done this, you can release the storage of the sequence without fear.

It is a strange thing that,  when i was a tutor, i taught students web design but they all interested in making flashing things like blink texts and cool flash effects. As they thought, flashing things attracted people’s attention, what a pity, they didn’t notice that flashing also took away the attention belonging to some other important contents. Going further, how long could people’s attention be, the answer is 1 to 3 minutes at most. Shocking, isn’t it ?There are several pitfalls of using flash things as important components:

1) SEO issues: google cann’t index the flash as good as normal ones, that is truth, at least until now it is that.

2) Flash player is another issue: nobody could say that every brower is campatible with the flash? The answer is NO.

 3) Some flash effects are not compatible. Like the effect showed in the picture above, it is some kind simulation of Mac’s Dock. What is it used for? Just show that it’s cool, funny or efficient? Neither, i think. 

In my opinion, just like the picture demonstrated below, clear, simple and accessable navigator plus inspirative design would be useful and helpful to all browsers. 

Several days ago, we published a new way to add ‘related posts’ function into wordpress without plugins, that works. And accidently  today, in smashingmagzine i found a similar way to update ‘related posts’ function:

<?php

$tags = wp_get_post_tags($post->ID);

if ($tags) { echo ‘Related Posts’;

$first_tag = $tags[0]->term_id;

$args=array( ‘tag__in’ => array($first_tag), ‘post__not_in’ => array($post->ID), ’showposts’=>5, ‘caller_get_posts’=>1 );

$my_query = new WP_Query($args);

if( $my_query->have_posts() ) { while ($my_query->have_posts()) : $my_query->the_post(); ?>

<p><a href=”<?php the_permalink() ?>” rel=”bookmark” title=”Permanent Link to <?php the_title_attribute(); ?>”>

<?php the_title(); ?></a></p> <?php endwhile; } }

?>

So now there are 2 ways to update the ‘related posts’ function into your blog.

Six feet by Lev Tsimring

envy by Fulvio Pellegrini

Please wait a little by Marc Siewior

Turtle and apple by Vedran Vidak

Collaboration by ryandws

Kung Fu Master by Lina Gunawan

Softdrink Addict by Andrei

About a dream by Jurga

Sunshine in a cup by She Hates Monday

Tired by Bill Mangold

Teaser by Johan Lind

So Hungry by Heath Carney

Say, Harold, haven’t we seen her before? by Ursula I Abresch

I’ll never talk to you again by Adrifil

Passionate by Ursula I Abresch

You are my best Friend by Jani

Ohhh Nooooo!!! by Mark B Bartosik

Anatomy Lessons by Paul van Geldrop

No Birds by Sameli

Bicho by Barbara C.

The Dancing Nebula

Infinity

Experiment Wall

Age Is Beauty

Loose Leaf

Motion Senses

A E R O S T R E A M

HD walls for windows

Experiment Wall

Explo Wall

Rainbow

Reflux

Horsehead Nebula

Ever Wondered?

Confused Trajects

Dusk

ONyx

Horizon

Zebra stripes

Blue Interlaced

Explode texture

Apple color shades

Epic

Leopard Aurora

Hologram Reflector

Used Crayons

Ultimate Vista

Last Stripes

Magma texture

Life Magic

Vortex Apple

Bunch of light vectors

Blue Apple logo

Abstract waves

Not thinking straight

Spirit Lanterns

When i noticed my blog andol.info lacking some popular functions like ‘related posts’, i decided to do it myself. I googled the ‘related posts’ but most of present results are about installing plugins, no code level tips are provided. I dont like using plugins in wordpress bacause huge number of plugins probably slow down the browsing speed. 

So i just hacked it myself: adding the 2nd post query-> matching the query conditions->get result & display & CSS. Some codes are shared below.

<div id=’rltpost’>

<?php

  if(get_the_category()) {

    echo”<p><strong>&nbsp;Posts may be of interest to you:</strong></p><ul>”;

    foreach((get_the_category()) as $category) {

      $query2 = new WP_Query(“cat=”.$category->cat_ID.”&showposts=3&orderby=rand”);

      while($query2->have_posts()):

      $query2->the_post();

?>

      <li><a href=”<?php the_permalink() ?>” title=”permalink to: <?php the_title() ?>”><?php the_title() ?></a></li>

<?php

      endwhile;

    }

    echo”</ul>”;

  }

?>

</div>

Instruction: just copy all the codes above to where you wanna show your ‘related posts’ section, and add the CSS style in current theme’s style.css file, done, enjoy.

1) Google is simple

Under the same technology & engineer conditions, Google makes simple products which are easy and fast to use; Yahoo, will make fantastic products too, but, probably, with some complicated functions which users dont need so much but which only confuse users. For example, GMAIL vs YMAIL; GTALK vs YAHOO! MESSAGER; and GOOGLE SEARCH vs YAHOO! SEARCH. That is the truth, if, one tool is able to archive one tast, the simpler, the better.

2) Yahoo! is aged

Just like human being, young people always have more strange ideas than aged ones, so is Yahoo!. Yahoo! was created on the first wave of internet which was populare with news, messages and information. While going to today, the third wave of internet has nearly pasted, Yahoo! still hasnt made imaginable products catering web2.0 users.

3) Google is creative

On the other side, Google is young and full of creation, especially its talent and energical engineers. They create all kinds of products, whether it is good or not, then, put the products into lab to test the response of usabilities. One by one, there increases the number of Google’s popular products and attracts users. 

Sometimes we dont know what users want, so we have to design all kinds of products according to the clues from web. Once we put the products on market, then, users will choose which ones are good and which ones aren’t — that is called rapid developing and fast evolution.

Now let me tell you my recent ebay experiences:

1) payment & registration & login

It is nearly the common sense that before starting deserving the services of a website, signing up is mandatory, absolutely no other choices. Suppose, all users have the choice to purchase some stuffs in eBay, probably the results would be that nobody like the petty registration stuffs. The important thing, if the account is not created for communication, then, it is useless for users. That only benifets the company. 

2) items search

No dout, that search is so important that if we lost it we would spend couple of times to find what exactly we want among numrous goods. However, search results’ items’ order is a problem. By price, the seller can publish low goods price plus expensive postage; by date, new stuffs maybe not the best ones; by place, how about a place like NewYork, millions of goods online; or, by combination of these search, do you think that will work out? My answer is NOT POSSIBLE.

Take Bill Gates for example, it is said that, one time, he visited microsoft.com to download a software, ironically, he was not able to find the software in the site although he knew it must be some where. The same thing, The CEO of eBay, maybe, couldnt find the right stuffs neither. 

3) design for goods’ display

With this problem, just open the eBay site, and you will find its massiveness. People come here only for watching the colorful page? Dont be stupid. When i go to apple.com, eigher i would buy some devices or get some related information of hardware or software. 

So, i think that is the first thing, display the propriate things what the users want, and display should be designed to cater the customers’ request.

How to get the gestures needed?
Generally, in order to detect hand and extract gestures from dymanic background environments, some algrithms such as color segment and some kinds of ‘mean’ algrithms are neccessary, indeed. And, as far as i have learned until now, i found 2 methods to effectively extract target gestures from background images. Those methods are color segment, motion detection and more advanced sensing like infrared detecting integrating with motion or color. This step is quit easy to archive because of the limited algrithms and hand characters which include color, motion and what? Nothing! Probably temperature, but that is not so universal.

What chatacters could be used for recognizing gestures?
  So, if the gestures are extracted from the complicated background images, the next step would be recognize them. Recognition is not as simple as detection which you just do some filter work. It needs several unique characters from the detected images. Most of the time, these characters probably contain: 1) angle – detecting the rotation   2) size – detecting the area   3)  peak and valley which is specific for the open hand  4) moving speed and direction. 

New google pagerank updated today, and andol.info’s rank increased to 2.

Related Posts: Hand guesture recognition using openCV

Clicking the pictures and the detailed previews will display which show the hand contours extracting from video capture. These pictures illustrate the results of color based segmentation for hand gesture detection ( not recognition yet ). it is a  real time programme,  however, in this demonstration, the programme still depends on environments’ light , because of the color based segmentation method. If, combinned with motion detection and background substraction, it supposes to be robuster.

Related Post:  Color recognition using openCV

Recognising colors in computer vision using openCV is not so complicated as it is expected. Actually, getting the capture image from webcam or some other advanced cameras, converting the color from RGB to HSV or HSI( not sure it is right ), and extracting the specific color(s) from the converted image, that is done. After that, some filters like CVSMOOTH, CANNY and CVTHRESHOLD can be applied to take off the noises in the previous image.

Give some codes here :

IplImage* src = cvCreateImage( sz, 8, 3 );

IplImage* hsv_image = cvCreateImage( sz, 8, 3);

IplImage* hsv_mask = cvCreateImage( sz, 8, 1);

IplImage* hsv_edge = cvCreateImage( sz, 8, 1);

CvScalar  hsv_min = cvScalar(0, 80, 80, 0);

CvScalar  hsv_max = cvScalar(20, 150, 255, 0);

/*

——————————————*/

src = cvQueryFrame( capture);

cvCvtColor(src, hsv_image, CV_BGR2HSV);

cvInRangeS (hsv_image, hsv_min, hsv_max, hsv_mask);

cvSmooth( hsv_mask, hsv_mask, CV_MEDIAN, 13, 0, 0, 0 );

cvCanny(hsv_mask, hsv_edge, 1, 3, 5);

According to the algrithms of  HOUGH, that is more accurate to line detection rather than circle detection, although some times it looks not so much different in theory. Actually, if detecting circles in a black-white picture, it will be obviously not so accurate as detection for lines. Detected circles are always flashing in different possible positions.

To solve this problem and low the mistake detection, the target picture should do some filter: SMOOTH.

cvSmooth( gray, gray, CV_GAUSSIAN, 11, 11 );
cvCanny(gray, edge, (float)edge_thresh, (float)edge_thresh*3, 5); //get the circle edges
CvSeq* circles =  cvHoughCircles( gray, cstorage, CV_HOUGH_GRADIENT, 2, gray->height/50, 5, 35 );
cout << circles->total <<endl; //check how many circles detected
int i;
for( i = 0; circles->total>=2?i<2:i < circles->total; i++ ){
float* p = (float*)cvGetSeqElem( circles, i );
cvCircle( src, cvPoint(cvRound(p[0]),cvRound(p[1])), 3, CV_RGB(255,0,0), -1, 8, 0 );
cvCircle( src, cvPoint(cvRound(p[0]),cvRound(p[1])), cvRound(p[2]), CV_RGB(200,0,0), 1, 8, 0);
}

From the birth of mouse and keyboard, people have been using these kinds of input devices for decades years, and now, it is the time to change. More nature interaction methods are booming, like multiTouch, camera detection and gesture cognizing technologies. By these new technologies, people in the future could be able to interact with computers naturely as parts of own body. The nature hand gesture congnizing is a demonstration of that trendancy. 

We indeed need new interaction ways to communicate with the physical world with higher effeciency.

In this post, as the progress goes, the hand detection technologies using openCV is introduced. As the pictures inllustrated below, this detection method is independent  with distance and background ( just not the background full of hands ), and the main segment method is color abstract which means getting the hand color pixels filtered. As the result tested within several environments, it workd well except slightly noise varying. But the noise is easy to take off.

The tested source code file is offered underneath the illustrations, feel free to use it.

SOURCE FILE HERE:  handDetection.CPP

After finished basic shapes recognition using openCV, we would step new progress — hand recognition. I saw some researchers said computer vision as key part of artificial intellegence due to its hardness. That probably is right, because when i started the hand detection ( before recognition ), i was blocked by the algrithms to accuratly detect the hand shape. Nothing simple algrithm will be applied directly here due to the variation of hand gestures.

When i googled how to detect hand gestures, i found  HandVu .

HandVu is a library of hand gesture recognition based on c++/c and openCV. According to the demoes published in web, this library looks powerful, although still is getting mature. When i tried to download the source files, i found the version hasnt been updated for years until 2006 and the downloaded binary didnt work right with alerts of *.dll files getting lost , that was probably caused by the openCV version.

Whatever, at least the HandVu library offered guidline of hand recognition.

In this post, i will present you the new progress of object recognition using openCV—angle recognition.

Actually, this is just a small step further than the last one which is rectangles’ recognition. From the four outlines of rectangle as well as the four corner points, we can get two relative points to calculat the angle between them. As inllustrated below, i chosed two points which are most left and right. Once the position of these two points are captured, the SINE value of the angle can be calculated like this

SIN (angle) = abs(p1.y-p2.y)/sqrt(
(p1.x-p2.x)*(p1.x-p2.x)+(p1.y-p2.y)*(p1.y-p2.y))

So, that’s it.

First-chance exception at 0×7c90eb74 in camera1.7.exe: 0xC0000008: An invalid handle was specified.

And, the debugging pointer was on the left side of the code:

capture = cvCaptureFromCAM(0);

Well, this line ran smoothly in Code:Blocks, why at here it went wrong.

However, i think, openCV’s default functions which are included in its library maybe probably have this abilities. As a result, today i found a openCV function called

CvConvexityDefect

-Structure describing a single contour convexity detect

and there is  a illustration picture on the side of the instruction like below:

So, until now, colors*shape*angle=>infinite, the future looks bright to code some application of interactive objects recognition. But these founded a problem that is memory leaking in C++. I am newbie of C++ and i used Actionscript to make codes which were automatically recyling all the memory trash. But now, the trash memory have to be delete manually, terrible nightmare to me.

However, when turns to rectangle recognition, it seems work right but not so much. Look carefully, there are multilines drawed on one rectangle detected, and the rectangle number displayed on the left side was totally wrong—too much rectangles, that was impossible because as i see that i just put 3 rectangles under the camera. As a result, i was sucked here and couldnt move forward.

If there’s any good idea, welcome to leave a comment or contact me.

In color recognition, it can detect any color, but there’s still a little bug that,  the detectation color should be preset before recognizing the objects in the destination image. I am not sure whether there’s any color filter in openCV like Actionscript3 which can just directly filter the necessary color objects.

Source code colorrecg.pdf