if ( ! function_exists( 'wp_handle_upload' ) ) {
	require_once( ABSPATH . 'wp-admin/includes/file.php' );
}

$uploadedfile = $_FILES['image'];
$filetmp = $_FILES['image']['tmp_name'];

$image_info = pathinfo($_FILES['image']['name']);
$ext = $image_info['extension'];

$exclude_upload_file_array = array('(',')','[',']','{','}','\'','"','#',' ','@',',','.','+',':');
$filetitle = str_replace($exclude_upload_file_array, '', $image_info['filename']);

$upload_overrides = array( 'test_form' => false );

$movefile = wp_handle_upload( $uploadedfile, $upload_overrides );

if ( $movefile && ! isset( $movefile['error'] ) ) {
	$filedest = $movefile['file'];
	$fileurl = $movefile['url'];

	include( ABSPATH . 'wp-admin/includes/image.php' );

	$attachment = array('post_title'=>$filetitle,
			'post_status'=>'inherit',
			'post_name'=>$filetitle,
			'post_type'=>'attachment'
	);

	if($ext){
		$attachment['post_mime_type']="image/".$ext;
	}

	$attach_id = wp_insert_attachment( $attachment, $filedest );

	$attach_data = wp_generate_attachment_metadata( $attach_id, $filedest );
	wp_update_attachment_metadata( $attach_id,  $attach_data );
}


---- Use Filter Code ----

if ( ! function_exists( 'wp_handle_upload' ) ) {
	require_once( ABSPATH . 'wp-admin/includes/file.php' );
}

$uploadedfile = $_FILES['image'];
$filetmp = $_FILES['image']['tmp_name'];

$image_info = pathinfo($_FILES['image']['name']);
$ext = $image_info['extension'];

$exclude_upload_file_array = array('(',')','[',']','{','}','\'','"','#',' ','@',',','.','+',':');
$filetitle = str_replace($exclude_upload_file_array, '', $image_info['filename']);

$upload_overrides = array( 'test_form' => false );

$movefile = wp_handle_upload( $uploadedfile, $upload_overrides );

if ( $movefile && ! isset( $movefile['error'] ) ) {
	$filedest = $movefile['file'];
	$fileurl = $movefile['url'];

	include( ABSPATH . 'wp-admin/includes/image.php' );

	$attachment = array('post_title'=>$filetitle,
			'post_status'=>'inherit',
			'post_name'=>$filetitle,
			'post_type'=>'attachment'
	);

	if($ext){
		$attachment['post_mime_type']="image/".$ext;
	}

	$attach_id = wp_insert_attachment( $attachment, $filedest );

	$attach_data = wp_generate_attachment_metadata( $attach_id, $filedest );

	// Apply filter....
	apply_filters( 'wp_update_attachment_metadata', $attach_data, $attach_id );
}