Add theme support for Custom Header

// Set content width value based on the theme's design
if ( ! isset( $content_width ) )
	$content_width = 1200;

// Register Theme Features
function custom_theme_features()  {
	global $wp_version;

	// Add theme support for Custom Header
	$header_args = array(
		'default-image'          => '',
		'width'                  => 400,
		'height'                 => 120,
		'flex-width'             => true,
		'flex-height'            => true,
		'random-default'         => false,
		'header-text'            => false,
		'default-text-color'     => '',
		'uploads'                => true,
		'wp-head-callback'       => '  ',
		'admin-head-callback'    => ' ',
		'admin-preview-callback' => '',
	);
	if ( version_compare( $wp_version, '3.4', '>=' ) ) :
		add_theme_support( 'custom-header', $header_args );
	else :
		add_custom_image_header();
	endif;

	// Add theme support for custom CSS in the TinyMCE visual editor
	add_editor_style( 'editor-style.css' );	

	// Add theme support for Semantic Markup
	$markup = array( );
	add_theme_support( 'html5', $markup );	
}

// Hook into the 'after_setup_theme' action
add_action( 'after_setup_theme', 'custom_theme_features' );