You need to set the value of `upload_max_filesize` and `post_max_size` in your php.ini :
; Maximum allowed size for uploaded files. upload_max_filesize = 50M ; Must be greater than or equal to upload_max_filesize post_max_size = 50M
After modifying `php.ini` file(s), you need to restart your HTTP server to use new configuration.
If you can't change your `php.ini`, you're out of luck. You cannot change these values at run-time; uploads of file larger than the value specified in `php.ini` will have failed by the time execution reaches your call to `ini_set`.
OR
Even you can set in `.htaccess` file of project
php_value upload_max_filesize 50M php_value post_max_size 50M

You need to set the value of `upload_max_filesize` and `post_max_size` in your php.ini :
<!-- language: lang-none -->
; Maximum allowed size for uploaded files. upload_max_filesize = 40M ; Must be greater than or equal to upload_max_filesize post_max_size = 40M
After modifying php.ini file(s), you need to restart your HTTP server to use new configuration.
If you can't change your php.ini, you're out of luck. You cannot change these values at run-time; uploads of file larger than the value specified in php.ini will have failed by the time execution reaches your call to `ini_set`.
See the [Description of core php.ini directives][1].
[1]:http://php.net/manual/en/ini.core.php