Add Cover Image Upload Option to Customizer

Add this to functions.php

// =========================================================================
// CUSTOMIZER COVER
// =========================================================================
function genesis_cover_customize_register( $wp_customize ) {

    // Add Settings
    $wp_customize->add_setting('customizer_setting_cover_image', array(
        'transport'         => 'refresh',
        'height'         => 325,
    ));

    // Add Section
    $wp_customize->add_section('cover_section', array(
        'title'             => __('Cover image', 'name-theme'), 
        'priority'          => 70,
    ));    

    // Add Controls
    $wp_customize->add_control( new WP_Customize_Image_Control( $wp_customize, 'customizer_setting_cover_image', array(
        'label'             => __('Add cover image', 'name-theme'),
        'section'           => 'cover_section',
        'settings'          => 'customizer_setting_cover_image',    
    )));
}
add_action('customize_register', 'genesis_cover_customize_register');

Call

<img src="<?php echo esc_url( get_theme_mod( 'customizer_setting_cover_image' ) ); ?>" alt="Cover image">

Hook cover v1

// =========================================================================
// COVER
// =========================================================================
add_action('genesis_before_content', 'cover');
    function cover(){
        if ( is_front_page() ){
            echo '<img class="cover" src="'.esc_url( get_theme_mod( 'customizer_setting_cover_image' ) ).'" alt="Cover Image">';
    }
}

Hook cover v2

// =========================================================================
// COVER
// =========================================================================
add_action('genesis_after_header', 'add_cover');
function add_cover(){
    if( is_front_page() ){
        include('inc/cover.php');
    }
}
include('functions/add-cover-to-customizer.php');