Ashok's Programming World

Debug() function for Opencart

2013-01-12T09:20:00.001-08:00

Have you wondered if a single function call would be sufficient to output the array in pre-formatted way. I have been working with opencart for some months and I realize how repititive is it to repeat same lines of code to make array look nice. By the way, I am a big fan of CakePHP framework and its powerful debugging technique.

<?php
   echo '<pre>';
   print_r($array);
   echo '</pre>';
?>
Whenever I need to echo any array, I needed to repeat the ‘<pre>’ so that I get readable array.

So, I thought of making a global function debug(), so that it takes array as argument and prints the array in a nice format.

For this, there is a need for making a global function, so that we can access this function whenever we require, like

<?php $this->debug($array); ?>

The debug function was added in the abstract class Controller after render() function at system/engine/controller.php and if you need it for model , system/engine/model.php.

  /*
   * @author Ashok Basnet
   * 2013-1-13
   * Debug function for opencart
   * @params array
   * @return true
   */
  public function debug($array){
    // show calling url : Line line_number
    $bt = debug_backtrace();
    $caller = array_shift($bt);
    echo '<b>'.$caller['file'].' : Line '.$caller['line'].'</b>';
    
    echo '<pre>';
    print_r($array);
    echo '</pre>';
    return true;
  }

I don’t think the core modification is a good idea, but if it can make your life easier, then why not…

 Happy Coding

vQmod installation in Opencart

2013-01-11T10:47:00.001-08:00

Interestingly, vQmod was originally developed for Open Cart ! But due to "openess" of the design, it has been used by other systems too.

In OpenCart (OC), extending your site's features usually results in modifying the program core codes. There are many reasons why this practise in not favorable - a major one is that it is not easily reversible. Say when you modified some codes and wanted to reinstate the original for some reason, it can be quite tedious.

This is due to the nature how OC handles extensions. Its normally done by overwriting existing codes instead of using plugin or module concepts employed in WordPress or Drupal. Honestly, this has been one of my top gripes about OC.

Installing on OpenCart

vQmod works on both OpenCart 1.4.x and 1.5.x

How to install using Autoinstaller

Download the latest version that has "opencart" in the title from
- http://code.google.com/p/vqmod
Using FTP, upload the "vqmod" folder from the zip to the root of your opencart store.
Be sure the vqmod folder and the vqmod/vqcache folders are writable (either 755 or 777).
- Also be sure index.php and admin/index.php are writable.
  - If not sure which you need, first try 755.
  - If you get errors about permissions, then try 777.
Goto http://www.yoursite.com/vqmod/install
You should get a success message. If not, check permissions above and try again
Load your store homepage and verify it works.
Using FTP, verify that there are new "vq" files in the "vqmod/vqcache" folder.
If yes, then you are ready to start downloading or creating vQmod scripts, otherwise ask for assistance.

Done!

Here is the video for assist.

How to install Manually

Download the latest version that has "opencart" in the title from
- http://code.google.com/p/vqmod
Using FTP, upload the "vqmod" folder from the zip to the root of your opencart store.
Be sure the vqmod folder and the vqmod/vqcache folders are writable (either 755 or 777).
- Also be sure index.php and admin/index.php are writable.
  - If not sure which you need, first try 755.
  - If you get errors about permissions, then try 777.
Edit your index.php file

FIND:

// Startup
require_once(DIR_SYSTEM . 'startup.php');

// Application Classes
require_once(DIR_SYSTEM . 'library/customer.php');
require_once(DIR_SYSTEM . 'library/currency.php');
require_once(DIR_SYSTEM . 'library/tax.php');
require_once(DIR_SYSTEM . 'library/weight.php');
require_once(DIR_SYSTEM . 'library/length.php');
require_once(DIR_SYSTEM . 'library/cart.php');
require_once(DIR_SYSTEM . 'library/affiliate.php');

REPLACE WITH:

// vQmod
require_once('./vqmod/vqmod.php');
$vqmod = new VQMod();

// VQMODDED Startup
require_once($vqmod->modCheck(DIR_SYSTEM . 'startup.php'));

// Application Classes
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/customer.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/currency.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/tax.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/weight.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/length.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/cart.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/affiliate.php'));

Note the affiliate library file may not exist on older systems. Basically any require_once(DIR_SYSTEM . 'library/xxxxxxxx.php');needs to be changed to use the vqmod->modCheck above in the same format. This also applies to any additional require_once files in the next step

Edit your admin/index.php file

FIND:

// Startup
require_once(DIR_SYSTEM . 'startup.php');

// Application Classes
require_once(DIR_SYSTEM . 'library/currency.php');
require_once(DIR_SYSTEM . 'library/user.php'));
require_once(DIR_SYSTEM . 'library/weight.php');
require_once(DIR_SYSTEM . 'library/length.php');

REPLACE WITH:

// vQmod
require_once('../vqmod/vqmod.php');
$vqmod = new VQMod();

// VQMODDED Startup
require_once($vqmod->modCheck(DIR_SYSTEM . 'startup.php'));

// Application Classes
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/currency.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/user.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/weight.php'));
require_once($vqmod->modCheck(DIR_SYSTEM . 'library/length.php'));

Load your store homepage and verify it works.
Using FTP, verify that there are new "vq" files in the "vqmod/vqcache" folder.
If yes, then you are ready to start downloading or creating vQmod scripts.

Done!

For managing vqmod from admin panel in opencart, you can download the following extension.

http://www.opencart.com/index.php?route=extension/extension/info&extension_id=2969&filter_username=rph

Virtual File Modification System (vQmod)

2013-01-11T10:27:00.001-08:00

Have you ever thought of modifying the core of any framework? Then vQMod is the best way to do it.

"vQmod™" (aka Virtual Quick Mod) is an override system designed to avoid having to change core files. The concept is quite simple... Instead of making changes to the core files directly, the changes are created as xml search/replace script files. These script files are parsed during page load as each "source" core file is loaded with the "include" or "require" php functions. The source is then patched with the script file changes, and saved to a temp file. That temp file is then substituted for the original during execution. The original source file is never altered. This results in a "virtual" change to the core during execution without any actual modification to the core files.

Features

No actual code changes are made. All changes are "virtual", hence the name.
Modifications are stored in their own files and applied "on-the-fly" at runtime
Instant Single file "plug-n-play". Add the file to apply the mod, remove the file to remove the mod.
No worries about losing custom core changes during upgrades
Multiple modifications can be made to the same file without conflict
Easily update or enhance customizations without having to edit any code
Full visual of the actual changes taking place in the generated temp files for debugging
Fails gracefully back to the original sourcefile if there is an error
Exceptional logging option to track every change made
Only need to modify the index.php file to add the vQmod code one time.
Simple structured xml format. (See readme for full breakdown of xml syntax)
Multiple options for find/replace, regex, positions, offsets, indexing, error handling, and more!

This system can be used for any php script, forum, shopping cart, cms, etc. Anywhere custom modifications are made for reuse. The logging option is invaluable for debugging understanding exactly what is happening.

For example,

'Replace' Example

Create a new text file and call it "replace-demo.xml"
Add the minimum required xml structure

Input

$var = 'ABC';

Script

<?xml version="1.0" encoding="UTF-8"?>
<modification>
        <id>Replace ABC with 123</id>
        <version>1.0</version>
        <vqmver>1.0.8</vqmver>
        <author>xxx</author>
        <file name="path/to/myfile.php">
                <operation>
                        <search position="replace"><![CDATA[
                        $var = 'ABC';
                        ]]></search>
                        <add><![CDATA[
                        $var = '123';
                        ]]></add>
                </operation>
        </file>
</modification>

Output

$var = '123';

For more details : http://code.google.com/p/vqmod/

Download the library : http://code.google.com/p/vqmod/downloads/list

Youtube API at Glance

2013-01-04T22:19:00.001-08:00

What is API ?

API ( Application Programming Interface )
Protocol intended to be used as an interface by software components to communicate with each other
A set of routines, protocols, and tools for building software applications.
A good API makes it easier to develop a program by providing all the building blocks.

What is youtube API

The YouTube APIs and Tools let you bring the YouTube experience to your webpage, application, or device.
It is possible to search for videos, retrieve standard feeds, and see related content. A program can also authenticate as a user to upload videos, modify user playlists, and more

Youtube APIs

1. Player API
2 Data API

Different Versions

Version 1
Version 2 ( Recommended )
Version 3 ( Experimental )

API for android

YouTube Android Player API ( Experimental)
https://developers.google.com/youtube/android/player/

Youtube Data API

Search for Videos	Search for Playlists	Search for Channels
- Keywords (tags) - Categories - Query Params (metadata)	- Keywords (tags) - Categories	- Keywords (tags) - Categories

Retrieve

–Videos

–Comments

–Captions

–Related Videos

–Video Responses

–Categories

–Keywords

–Playlists

–Subscriptions

–Profiles

–Contacts

–Messages

–Activity Feeds

–Insight Data Feed

–Favorites

Create

–Videos

–Comments

–Captions

–Related Videos

–Video Responses

–Complaint

–Rating

–Contact

–Message

–Favorite

–Playlist

–Subscription

Update

–Video Metadata

–Captions

–Profiles

–Playlists

–Contacts

Delete

–Video

–Message

–Favorite

–Playlist

–Subscription

–Contact

Getting Youtube data

http://gdata.youtube.com/feeds/api/videos/VIDEO_ID?v=2&alt=json

Suppose you want to get data for the video:-

For e.g.
http://gdata.youtube.com/feeds/api/videos/9bZkp7q19f0v=2&alt=json

alt => json or xml

Gives JSON Data as

    "version": "1.0",

    "encoding": "UTF-8",

    "entry": {

        "published": {

            "$t": "2012-07-15T07:46:32.000Z"

},

        "title": {

            "$t": "PSY - GANGNAM STYLE (강남스타일) M/V"

},

        "media$group": {

            "media$category": [

                    "$t": "Music",

                    "label": "Music",

                    "scheme": "http://gdata.youtube.com/schemas/2007/categories.cat"

],

"media$description": {

                "$t": "PSY - Gangnam Style (강남스타일) \n App Store: http://goo.gl/l9TU6\nGoogle Play: http://goo.gl/UiEn1\n\n© YG Entertainment Inc. All rights reserved.",

},

            "yt$duration": {

                "seconds": "253"

},

        "yt$statistics": {

            "favoriteCount": "0",

            "viewCount": "1121801092"

},

        "yt$rating": {

            "numDislikes": "523231",

            "numLikes": "6549910"

It gives more data than this. Yout get title, category, stats, ratings etc. I have tried to show you few of these.

For formatting json data:-

http://jsonlint.com

For more info
https://developers.google.com/youtube /

jQuery implementation of Game of life!

2012-08-07T03:07:00.001-07:00

One of the earliest experiments at simulating life in technology was a simple mathematical game created by John H. Conway, first published and popularized during the early 1970's in issues of Scientific American. He called it "The Game of Life."
The concept of the Game of Life is very simple. The game takes place over the cells in an array, like squares on a chessboard. Each cell can have an organism living inside it or not living inside it; or each cell itself can be alive or dead. Whatever frame of thought is used, each cell is described to be "on" or "off." At the beginning of the game, a certain number of cells are filled.

Methodology

Then the game begins. Every clock-tick, a new generation of cells is created. A set of rules is applied to each cell in the array to determine what will happen to the cell in this next generation. The rules are as follows:

If a cell is off and has three neighbors around it which are on, then the cell becomes on.
If a cell is on and has one or less neighbors around it which are on, the cell dies of loneliness (it becomes off).
If a cell is on and has more than three neighbors around it which are on, the cell dies of overcrowding.

Gameplay strategy
The game of life is a zero player game devised by mathematician John Horton Conway and explained by Scott E Page on the Coursera website in one of the videos on model thinking. The game is a grid of cells and each cell has a 'on' and a 'off' state or in other words, an 'alive' or 'dead' state. It has simple rules that can create complex patterns over time. If a cell is alive, then it can continue to 'live' only if it has exactly 2 or 3 neighboring cells alive, else it dies or goes 'off'. A dead cell can come alive only if it has exactly 3 neighboring cells alive. Over time, this creates intricate patterns and even animations! Certain patterns create 'blinkers' or even spawn into many more cells and spread across the grid.
Some screenshots
1. Initial State
2. Growth of Cell
Other interesting patterns can be developed too.
Here is the link for the JQuery Implementation.

Enable telnet in windows 7

2012-08-01T21:25:00.001-07:00

Windows 7 doesn’t provide access to telnet client in default. More than likely this was an attempt to make Windows more secure by default, as Telnet is very insecure and whenever you have the choice you should always use SSH. However, with that being said, you can quickly re-enable Telnet by following these steps:

Start
Control Panel
Programs And Features
Turn Windows features on or off
Check Telnet Client
Hit OK

or just search for windows featuers in start menu

After that you can start Telnet via Command Prompt.

Accessing localhost from Andriod Emulator

2012-07-11T04:52:00.001-07:00

The access of localhost in normal way can be bit tricky in Andriod SDK.

The normal way of accessing the localhost is :-

http://localhost or http://127.0.0.1

but when it comes to Andriod, we can’t directly access the localhost. For that use the followling address:-

http://10.0.2.2 or http://10.0.2.2/project-folder

Reach: An approach to bridge the digital divide[LOCUS 2012]

2012-07-06T20:05:00.001-07:00

Information and communication technologies(ICT) in general, and the Internet and the world wide web in particular, have made life easier by facilitating easy communication with virtually everyone, and easy access to information located virtually anywhere in the world. But all these communication technology are in reach of rich peoples, poor peoples are still backward in our country. Which have also widened the gap between the rich and the poor. In other words, new technologies, while improving our life in many ways have created the digital divide between the village and urban people.
Our application “Reach” tries to bridge this digital divide between them. Village people having simple mobile set can chat through sms to their family staying in foreign or city. In village there is no access of internet but in city there is access of internet and other communication facilities. “Reach” is a web chat application that user can send sms to the mobile number directly where there is no access of internet and mobile user send sms back to web .
It’s a two way chat, the user having access to internet needs to signup to the web app that we developed and the mobile user can send sms to the user by typing a [keyoword] followed by [username] to 4001.
CHAT Username Message to 4001.
The web user gets notifications and the history is also maintained.
The system block diagram is as follow:-

Here are some screenshots:-
1. Home Screen

2. Chat Interface

3. Notifications

4. Some forms


Login or register	Signup screen

Login Screen	Add Contact

5. Mobile message sending

1st Runner Up for Theme Based Competition @LOCUS 2012

A <base_2 > project:-
Aayush Shrestha
Ashok Basnet
Bibek Subedi
Dinesh Subedi

References:-

Sparrow SMS for the SMS gateway
http://api.sparrowsms.com

Randomly generate password in SQL Server 2008

2012-06-28T05:53:00.001-07:00

There are lots of ways of generating random strings in SQL Server. But instead of spending much time on finding solution to random password generation, here is an easy way to do that.

SELECT SUBSTRING(convert(varchar(50),NEWID()),0,8) as password

This generates 8 charcters long password which is a random string.

Some results:-

673CB61

6BD26C7

7F5F1EB

Using Cursor to iterate through records in sql server 2008

2012-06-28T04:00:00.001-07:00

Cursors are great way to loop through records in SQL specialy when you need to deal with individual records from certain table.

Here is a example using cursor;

DECLARE @StudentID char(11);
  
DECLARE crs CURSOR READ_ONLY
FOR
SELECT student_id
FROM students
OPEN crs
FETCH NEXT FROM crs
INTO @StudentID
WHILE @@FETCH_STATUS = 0
BEGIN
  PRINT @StudentID
  FETCH NEXT FROM crs
  INTO @StudentID
END
CLOSE crs
DEALLOCATE crs

The definitions for the terminology are :-

DECLARE CURSOR
    this statement defines the SELECT statement that forms the basis of the cursor.
    You can do just about anything here that you can do in a SELECT statement.
OPEN
    statement executes the SELECT statement and populates the result set.

FETCH
    statement returns a row from the result set into the variable.
    You can select multiple columns and return them into multiple variables.
    The variable @@FETCH_STATUS is used to determine if there are any more rows.
    It will contain 0 as long as there are more rows.
    We use a WHILE loop to move through each row of the result set.

READ_ONLY clause is important in the code above. That improves the performance of the cursor.

CLOSE statement releases the row set

DEALLOCATE statement releases the resources associated with a cursor.

Note **
Please note that cursors are the SLOWEST way to access data inside SQL Server.
The should only be used when you truly need to access one row at a time.

Conversion of Imperial to Metric System in SQL Server 2008

2012-06-26T09:18:00.001-07:00

There will be case when you need to convert the values in Imperial system i.e. in feet and inches to the one in metric system. The conversion logic seems simple, but when it comes to SQL Server, it takes a bit complex.

Here is the function which can convert imperial unit of measurement to the metric system.

CREATE FUNCTION [dbo].[fncImperialToMetric]
(
	@ImperialInput VARCHAR(50)
)
RETURNS FLOAT
AS
BEGIN
	-- Declare the return variable here
	DECLARE @Result FLOAT;
	DECLARE @myFeet as varchar(50);
	DECLARE @myInch as varchar(50);
	
	
	set @ImperialInput = RTRIM(ltrim(@ImperialInput));
	set @myFeet='';
	-- SEPARATE FEET AND INCH SECTION
	-- GET THE FEET SECTION
	if (CHARINDEX('''', @ImperialInput)-1)>0
		set @myFeet = SUBSTRING(@ImperialInput,1,CHARINDEX('''', @ImperialInput)-1);
	--GET THE INCH SECTION	
	set @myInch = REPLACE(@ImperialInput,@myFeet ,'');
	set @myInch = REPLACE(@myInch,'''' ,'');
	set @myInch = REPLACE(@myInch,'"' ,'');
	
	set @Result = cast(@myFeet as float) * 12 + CAST( @myInch as float);
	set @Result = cast(cast(@Result as int)* 0.0254 as numeric(6,2));
	Return @Result;

Run the following SQL Query to test the results:-

SELECT [dbo].fncImperialToMetric ('5'' 10"'),
  [dbo].fncImperialToMetric ('5'' 2'),
  [dbo].fncImperialToMetric ('5'''),
  [dbo].fncImperialToMetric ('10'), 
  [dbo].fncImperialToMetric ('10"')

The results are:-

Reset indentity value of Auto increment Key to 0 in SQL server 2008

2012-06-26T09:03:00.001-07:00

I have been searching for resetting the Auto increment value of ID Column in MSSQL Server 2008 and finally solved the problem. You can simply do the following in SQL.

The following line resets the Identity value for the ‘MyTable’ table to 0 so that the next record added starts at

DBCC CHECKIDENT(‘MyTable’, RESEED, 0)

The truncate command can also does the trick but its not applicable if there are some foreign key constraints.

For more information on DBCC CHECKINDENT you can refer MSDN.http://msdn.microsoft.com/en-us/library/ms176057.aspx

Detect face area using Matlab

2012-05-07T11:32:00.001-07:00

Image processing can be used to process various objects in various ways and one for them is the face detection. The face detection system has got many applications and developing such a system is even easier by use of the Image Processing ToolBox available in MATLAB.

The detection of face involves various tasks. They can be summarized in three steps as:-

reading of a RGB image
minimisation of background portion
detection of face object

Here is the code for the detection of the face area. Save it as filename.m file and execute the code in matlab.

%%%%% Reading of a RGB image

i=imread('imagepath');  % for eg. C:\P1140119.jpg

I=rgb2gray(i);

BW=im2bw(I);

figure,imshow(BW)

%%%%% minimisation of background portion

[n1 n2]=size(BW);

r=floor(n1/10);

c=floor(n2/10);

x1=1;x2=r;

s=r*c;

for i=1:10

    y1=1;y2=c;

    for j=1:10

        if (y2<=c | y2>=9*c) | (x1==1 | x2==r*10)

            loc=find(BW(x1:x2, y1:y2)==0);

            [o p]=size(loc);

            pr=o*100/s;

            if pr<=100

                BW(x1:x2, y1:y2)=0;

                r1=x1;r2=x2;s1=y1;s2=y2;

                pr1=0;

end

            imshow(BW);

end

            y1=y1+c;

            y2=y2+c;

end

 x1=x1+r;

 x2=x2+r;

end

 figure,imshow(BW)

 %%%%% detection of face object

L = bwlabel(BW,8);

BB  = regionprops(L, 'BoundingBox');

BB1=struct2cell(BB);

BB2=cell2mat(BB1);

[s1 s2]=size(BB2);

mx=0;

for k=3:4:s2-1

    p=BB2(1,k)*BB2(1,k+1);

    if p>mx & (BB2(1,k)/BB2(1,k+1))<1.8

        mx=p;

        j=k;

end

end

figure,imshow(I);

hold on;

rectangle('Position',[BB2(1,j-2),BB2(1,j-1),BB2(1,j),BB2(1,j+1)],'EdgeColor','r' )

The sample output for the image read from my computer is shown below:-

The final output is the one with detected area of the face.
The algorithm can be extended to detect even more precisely the area of the face.

Extract Frames from Video MATLAB

2012-03-13T10:59:00.001-07:00

There may be situations when we need certain frames from video. You can extract the video frames easily in MATLAB and save to any image format that MATLAB imwrite function supports or you can process the frames directly.

There is a function class called ‘VideoReader’

OBJ = VIDEOREADER(FILENAME)
- constructs a multimedia reader object, OBJ, that can read in video data from a multimedia file.
- FILENAME is a string specifying the name of a multimedia file. There are no restrictions on file extensions.

MMREADER can also be used but MMREADER will be removed in a future release. So better use ‘VideoReader’.

Here is the code to do it.

%vid = video which needs to be extracted
vid = 'worm_gear_set.avi';
readerobj = VideoReader(vid);
vidFrames = read(readerobj);
%get number of frames
numFrames = get(readerobj, 'numberOfFrames');
for k = 1 : numFrames
    mov(k).cdata = vidFrames(:,:,:,k);
    mov(k).colormap = [];
    %imshow(mov(k).cdata);
    imagename=strcat(int2str(k), '.jpg');
    %save inside output folder
    imwrite(mov(k).cdata, strcat('output\frame-',imagename));
end

The frames extracted are saved inside the output folder which will be inside the project directory.

You can download the project files from here.

Number Plate Extraction using MATLAB

2012-02-26T02:09:00.003-08:00

The number plate extraction in MATLAB can be accomplished using Image Proccessing Tools available in MATLAB. The functions provided by the Image Processing ToolBox makes it easy to process any images to extract the data from it.
The algorithm for extracting number plate can be summarized as:-
Input Image

1.Capture image from webcam.
2.Store the captured image into a image file for further processing.

Convert Image into Binary

If image intensity = high Reduce intensity Else if intensity = low Increase intensity Else No change.

3.Calculate appropriate threshold value for the image.

4.Convert the image into binary image using the calculated threshold.Detecting Number plate area

If number of ‘white’ pixels < x; pixels become ‘black’ Else; no change If number of ‘white’ pixels > y; pixels become ‘black’ Else; no change The value of x and y may be changed according the image intensity and plate area.

5.Check number of possible areas.

6. Logically AND with binary image obtained at “Convert image into binary algorithm.

7.Crop the required area.Segmentation

1.Filter the noise level present in the image.

2.Clip the plate area in such a way that only numbers of plate area extracted.

3.Separate each character from the plate.Number Identification

1.Create the template file from the stored template images.

2.Resize image obtained from segmentation to the size of template.

3.Compare each character with the templates.

4.Store the best matched character. Save to file in given format

1.Open a text file in write mode (append mode in case of the multiple records).

2.Store the character obtained from the number identification process to text file in given format.

3.Close the fileSome of the snapshots for the number plate extractions:-

Pic 1:- Number plate that is to be extracted.
Open the main.m file in MATLAB.

Now run the main.m file in the MATLAB. It may prompt you to change the default directory. You can either change folder or Add to Path. Better change the directory.

You will get a messagebox showing the extracted number plate. Message box like this:-

The log file ( log.txt ) is maintained to keep track of the saved number plates ( which can be used in application level ). The log file content contains the number plate with the date saved.

In main.m there are certain lines which when commented can be used to see the step by step characters extraction.

Feel free to ask any queries if any problem occurred. I am using MATLAB 7.12.0 (R20011a) but it should work in all version.
Download the whole project here.
The project involving the number plate extraction :- ANPR(Automatic Number Plate Recognition) Using ALR(Automatic Line Tracking Robot).

Node.js : Introduction

2012-02-23T04:01:00.001-08:00

Node.js is a platform built on Chrome's JavaScript runtime for easily building fast, scalable network applications. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.

Node.js was created by Ryan Dahl starting in 2009

Traditional Web Servers

The “traditional” mode of web servers has always been one of the thread-based model. You launch Apache or any other web server and it starts receiving connections. When it receives a connection, it holds that connection open until it has performed the request for the page or whatever other transaction was sent. If it make take a few microseconds to retrieve a page from disk or write results to a database, the web server is blocking on that input/output operation. (This is referred to as “blocking I/O“.) To scale this type of web server, you need to launch additional copies of the server (referred to as “thread-based” because each copy typically requires another operating system thread).

Node.js Event Driven Mechanism

In contrast, Node.js uses an event-driven model where the web server accepts the request, spins it off to be handled, and then goes on to service the next web request. When the original request is completed, it gets back in the processing queue and when it reaches the front of the queue the results are sent back (or whatever the next action is). This model is highly efficient and scalable because the web server is basically always accepting requests because it’s not waiting for any read or write operations. (This is referred to as “non-blocking I/O” or “event-driven I/O“.)

To put it a bit more concretely, consider this process:

You use your web browser to make a request for “/mypage.html” on a Node.js web server.
The Node server accepts your request and calls a function to retrieve that file from disk.
While the Node server is waiting for the file to be retrieved, it services the next web request.
When the file is retrieved, there is a callback function that is inserted in the Node servers queue.
The Node server executes that function which in this case would render the “/mypage.html” page and send it back to your web browser.

Here is a video on youtube by Ryan Dahl on node.js.

You can have further information and download link from the node,hs official site. http://nodejs.org

MATLAB and Image Processing

2012-02-23T03:03:00.001-08:00

Matlab contains a huge resources for image processing. It has Image Processing Toolbox which can be used to process any kind of image files.Image Processing Toolbox™ provides a comprehensive set of reference-standard algorithms and graphical tools for image processing, analysis, visualization, and algorithm development. You can perform image enhancement, image deblurring, feature detection, noise reduction, image segmentation, spatial transformations, and image registration. Many functions in the toolbox are multithreaded to take advantage of multicore and multiprocessor computers.

Below is the screenshot to access the Image Processing Toolbox of the MATLAB. You can view deoms and other help section to get started with Image Processing in MATLAB.

Key Features

Image enhancement, filtering, and deblurring
Image analysis, including segmentation, morphology, feature extraction, and measurement
Spatial transformations and image registration
Image transforms, including FFT, DCT, Radon, and fan-beam projection
Workflows for processing, displaying, and navigating arbitrarily large images
Modular interactive tools, including ROI selections, histograms, and distance measurements
ICC color management
Multidimensional image processing
Image-sequence and video display
DICOM import and export

Help Section in MATLAB is a great way to get started. Screenshot for the help section for the Image Processing Toolbox is :-

More tutorials on image processing will be published. Stay tuned.

Model View Controller ( MVC ) Architecture

2012-02-23T02:25:00.001-08:00

MVC Framework is a software architecture used in software engineering. Model View Controller (MVC) pattern creates applications that separate the different aspects of the application (input logic, business logic, and UI logic), while providing a loose coupling between these elements.

The model manages the behaviour and data of the application domain, responds to requests for information about its state (usually from the view), and responds to instructions to change state (usually from the controller). In event-driven systems, the model notifies observers (usually views) when the information changes so that they can react.

The view renders the model into a form suitable for interaction, typically a user interface element. Multiple views can exist for a single model for different purposes. A view port typically has a one to one correspondence with a display surface and knows how to render to it.

The controller receives user input and initiates a response by making calls on model objects. A controller accepts input from the user and instructs the model and a view port to perform actions based on that input.

An MVC application may be a collection of model/view/controller triads, each responsible for a different UI element. The Swing GUI system, for example, models almost all interface components as individual MVC systems.

Though MVC comes in different flavors, control flow is generally as follows:
The user interacts with the user interface in some way (i.e. View).
The controller handles the input event from the user interface, often via a registered handler or callback, and converts the event into an appropriate user action, understandable for the model.
The controller notifies the model of the user action, possibly resulting in a change in the model's state. (For example, the controller updates the user's shopping cart).
A view queries the model in order to generate an appropriate user interface (for example the view lists the shopping cart's contents). The view gets its own data from the model. In some implementations, the controller may issue a general instructio n to the view to render itself. In others, the view is automatically notified by the model of changes in state (Observer) that require a screen update.
The user interface waits for further user interactions, which restarts the control flow cycle.

Some of the famous MVC Framework implementations in different language:-
PHP
CakePHP
Zend Framework
CodeIgniter
Symfony Framework

Ruby on Rails

JAVA
Spring Framework
Struts
JSF

LOCUS 2011 : Projects ( C.yber and IoeCamPlus)

2011-07-22T03:35:00.001-07:00

This year locus, we have showcased two projects , one from previous year locus project and another C++ project .

You can have look at them at following link:-

1. C.yber

2. IoeCamPlus : v2.0ß

Some screenshots :-

IoeCamPlus : v2.0ß realeased

2011-07-22T02:45:00.001-07:00

IoeCamPlus is a cross platform webcam application With the problems faced with IoeCamPlusv1.0, the 2nd version of IoeCamPlus is released.

Updates in the IoeCamPlusv2.0ß :-

Image saving problem in v1.0 is solved.
new dll files installation updated.
Painter added for images browsed.
Error handling in case of missing camera hardware added etc.

You can download the source and installation file:-

Your feedbacks are important for us to improve the IoeCamPlus. So do comment….

Writing blogs offline using Live Writer

2011-07-14T22:44:00.001-07:00

Blogging is one of my key interest and those who are blogging in bloggers sites like blogspot, wordpress, etc. might be facing problems with the blog editor i.e. working online. I have been using Windows Live Writer for from 2009 and it is really a great tool for blogging. There are cool features that you are going to love about live writer. Blogging will be fun with live writer.

I have noted down some key features in Live Writer that I have observed.

The blogs can be saved offline and edited any time you want.
Multiple blogs accounts can be integrated so that you can switch to your blog on fly.
Its IDE is cool. You will not feel difficult with its IDE since it is somewhat like Office package.
Theme can be pulled at any time and refreshed if it is changed.
Categories can be set and post date can also be set before posting.
You can insert pictures, hyperlinks, videos and many more within live writer.
You can preview your blogs and view source code by using tabs at bottom of the live wirter software.
Different plugins are there which can be very useful like Source code ( for putting codes in the post.
After you have done editing and ready to be published , you can click publish icon at top.

The following screenshots will guide you through the steps for setting up the live writer. The live writer I am usign is Live Writer 2011 and the following guide can be useful for any blogs. Here I have used my blogger blog http://http://computer-engineering-in-nepal.blogspot.com/.

1. Download the live writer.

2. After installing the live writer you will be asked to fill a form for the blog account.

3. If you have your own blog , go to other services for blogger. You can choose wordpress directly from the option if you have a wordpress blog.

3. Click Next and the following form appears where you can fill up your blog details.

4. Fill up the form.

5. Note:- if you have proxy, set the proxy by cliking the link Set Proxy… . and click Manually configure setting.

6. Now the blog will set up message appears and click Finish button.

7. The live writer will pull the blog, its theme and you can get started.

8. Now here is the final outcome.

9. You can start writing blogs offline and publish it whenever you are online. The preview and source button at bottom of the live writer can be useful to view the blog before publishing and editing the source.

Preview

Source code

10. You can add plugins by downloading them from the internet and installing plugin.

11. You can manage multiple blogs also.

Happy blogging

Networking programming in C

2011-07-14T11:56:00.001-07:00

Networking has become an integral part of our everyday life and we are in some way connected to others. It has revolutionized the way we are living. Many times we need our application to write some data into a file, stored on a remote machine connected through a network, display some message in desktop of remote machine or simply exchange messages across the machines connected to the network.

C is an intermediate programming language which is very powerful in terms it is a high level language as well as it is able to access the hardware very efficiently and effectively. Computer Network means a collection of computers connected either by some means of wire or wireless technology to share data, resources etc. So network programming is important to learn and be able to understand how networks can be programmatically controlled.

JQuery Tutorial–II : Basic CSS Selectors

2011-07-08T03:49:00.001-07:00

Selectors in JQuery is used to select specific document objects like <body>, <h1>, <p>, <a> and many more. It’s use has made writing JQuery very easier and get the required DOM to have control over it.

Using Basic CSS Selectors

Any DOM element may have their unique ID or group of selctors may have a common class for styling. The ID selects unique element from the HTML DOM and class is applied for a wide selection. For eg.

<p id="myParagraph">
  This is the paragraph with ID attribute.
<p>
<p class="ourParagraph">
  This is first the paragraph with Class attribute.
</p>
<p class="ourParagraph">
  This is second paragraph with Class attribute.
</p>

For accessing these ids and classes of paragraph it can be done as :-

<script type="text/javascript">
  $('p#myParagraph').click(function(){
     alert('You clicked ID');
  });
  $('p.ourParagraph').click(function(){
     alert('You clicked Class');
  });
</script>

The p#myParagraph selects the paragraph with ID of myParagraph and p.myParagraph slects all the paragraph with class of ourParagraph.Each id value must be used only once within a document. If more than one element has been assigned the same id, queries that use that id will only select the first matched element in the DOM.

For applying styles to page elements, group of selection methods that work across all
browsers can be applied. Those methods include selection by an element’s ID, CSS class name,
tag name, and the DOM hierarchy of the page elements.
Here are some examples to give you a quick refresher.

a - This selector matches all link (<a>) elements.
#specialID—This selector matches elements that have an id of specialID.
.specialClass—This selector matches elements that have the class of specialClass.
a#specialID.specialClass—This selector matches links with an id of specialID
and a class of specialClass.

These basic selectors are powerful, but sometimes we need even finer-grained
control over which elements we want to match. jQuery meets this challenge and
steps up to the plate with even more advanced selectors.

JQuery Tutorial - I : Getting Started

2011-07-02T23:20:00.001-07:00

JQuery is very great tool for accessing the DOM(Document Object Model) elements is any webpage. JQuery is really a cool Javascript. In this tutorial I am going to show you how to use Jquery to make life easier without having to know all the Javascript lengthy codes or statements.

First of all u need is the Jquery file downloaded from the JQuery site or a link of Google code repository for JQuery. U can either download the development version for testing purposes or min version for depolyment purpose. After u download, create a webpage of ur choice and put your jquery.file into the folder.

I will be teaching you some events handling with the simple JQuery selectors. Lets get started. Lets create a page called index.html.

<html>
<head>
	<title>JQuery Tutorial I - Getting Started</title>
</head>
<body>
	<h2>JQuery Tutorial I- Getting Stared</h2>
	<a href="#">Show</a><br />
	<p>This is JQuery Tutorial demonstrating the use of JQuery and its easiness to access and manipulate the DOM elements.</p>
</body>
</html>

index.html

Here I have just created a index.html with simple HTML tags.

Now the in the <head> … </head> section of the HTML , insert the Javascript code i.e. our JQuery code as shown below:

	<script type="text/javascript" src="jquery.js"></script>

Test whether or not the JQuery is working by alerting some information.

<script type="text/javascript">
	$(function(){
		alert("Page successfully loaded.");
	});
</script>

Now time for some cools stuffs with selectors…. Lets control the paragraph property by using link selectors to change the visibility of the paragraph.

Lets alert when a href is clicked. U can do this simply by following JQuery..

<script type="text/javascript">
	$(function(){
		$('a').click(function(){
			alert("A href was clicked.");
		});
	});
</script>

You can also change the visibility using toggle () function which shows and hides alternatively.

<script type="text/javascript">
	$(function(){
		$('a').click(function(){
			$('p').toggle();  // shows and hide with clicks alerternately
		});
	});
</script>

In this way JQuery can be easily integrated into your website and there are lot more possibilites with JQuery and its selectors. In next Tutorial we will be dealing with different CSS selecors….

U can download the above tutorial from here..

JQuery : Introduction

2011-06-29T12:50:00.001-07:00

JQuery is a lightweight JavaScript framework developed by John Resig.

JQuery is a lightweight "write less, do more" JavaScript library.

The jQuery library contains the following features:

HTML element selections
HTML element manipulation
CSS manipulation
HTML event functions
JavaScript Effects and animations
HTML DOM traversal and modification
AJAX
Utilities

Adding the jQuery Library to Your Pages

The jQuery library is stored as a single JavaScript file ( u can get a copy of it from the JQuery site), containing all the jQuery methods. It can be added to a web page with the following mark-up:

  1: <head>
  2: <script type="text/javascript" src="jquery.js"></script>
  3: </head>

You can use the alternate version of the JQuery by referring to the site..

  1: <script type="text/javascript" 
  2:      src="="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js">
  3: </script>

To start using JQuery,

  1: <script type="text/javascript">
  2: $(document).ready(function(){
  3:       //Your JQuery code
  4: }};
  5: </script>

The JQuery loads the functions after only when all the DOM elements get loaded.

jQuery Syntax

The jQuery syntax is tailor made for selecting HTML elements and perform some action on the element(s).

Basic syntax is: $(selector).action()

A dollar sign to define jQuery
A (selector) to "query (or find)" HTML elements
A jQuery action() to be performed on the element(s)

Examples:

$(this).hide() - hides current element

$("p").hide() - hides all paragraphs

$("p.test").hide() - hides all paragraphs with class="test"

$("#test").hide() - hides the element with id="test"