EE610_GUI

This Repository is part of an Assignment of the course EE610 at EE Department, IIT Bombay.

The main goal of this is to make a small image editor tool.

Requirements

• Apache, php, python
• Python Modules: numpy, skimage

Features

This Code can perform the following tasks:

• Upload an Image
• Do Image histogram equalisation
• Do Gamma Correction
• Do Log Transform
• Save the Image

Key Words

AJAX, POST, GET, CGI

There is nothing to get scared about these terms, they are just some fancy names.

• AJAX: Used for sending / receiving Information without reloading a web page

You can refer this page for a basic introduction and working examples.

• POST, GET: Method used for sharing Information in the above step

You can refer this page for more information.

• CGI: Used in APACHE settings to enable execution of python scripts

You can refer this pgae for more information.

• .htaccess: settings can be mentioned in this file for each specific directory.

You can refer this page for more information.

SETUP

I have tested this code in xubuntu 16.04 and ubuntu 16.04, but i am 99% sure that this will work in all ubuntu machines..

Following are the steps to be followed for using this code on a fresh machine

• Setup APACHE.

sudo apt install apache2

• Copy this code to web directory (/var/www/html/)

cd /var/www/html

git clone https://github.com/TummanapallyAnuraag/EE610_GUI.git gui

• Enable CGI execution in apache2

sudo a2enmod cgi

sudo service apache2 restart

• Add the following lines of code in /etc/apache2/sites-enabled/000-default.conf

<Directory "/var/www/html/gui">
	AllowOverride All
</Directory>

• After any kind of changes to apache2 configuration files, we need to reload it.

sudo service apache2 restart

• Check if CGI scripts are being run, a hello world program is made for this special purpose only.

Check the CGI script working by going to http://localhost/gui/scripts/hello.py

• Once all the above steps are done, the GUI can be seen at http://localhost/gui

But if you face any problems while any of the steps, you can debug them with help of next step

• (Optional) If you want debug information, add this line of code to the same 000-default.conf file

LogLevel debug

You can see the debug information in /var/log/apache2/error.log

This command comes in handy at times..

tail -f /var/log/apache2/error.log

Web Help: look in StackOverflow

Worst case scenario: You can always drop a mail to me. You can find my details here

• Remember: Always restart apache2 service whenever you chnage the configuration files of apache2

SOME COMMON ISSUES

• If you are not able to upload images..

a) Check if the folder images has 777 permissions. If not you can do so by using

sudo chmod -R 777 images/

The -R is used for recursion (folder within folder scenario)

Also change the owner to www-data

sudo chown -R www-data:www-data images/

b) The image upload size must be more than the permissible limit.

You can check and change this permissible limit in /etc/php/7.0/apache2/php.ini