Adding manageable pictures in backoffice magento to push in any page.

adminhtml.xml

<!-- local/Namespace/MyModule/etc/adminhtml.xml -->
<?xml version="1.0" encoding="utf-8" ?>
<config>
     <acl>
        <resources>
            <admin>
                <children>
                    <system>
                        <children>
                            <config>
                                <children>
                                    <namespace_module translate="title" module="namespace_module">
                                        <title>namespace_module : Configuration</title>
                                    </namespace_module>
                                </children>
                            </config>
                        </children>
                    </system>
                </children>
            </admin>
        </resources>
    </acl>
</config>

config.xml

<!-- local/Namespace/MyModule/etc/config.xml -->
<?xml version="1.0" encoding="utf-8"?>
<config>
    <modules>
        <Namespace_Module>
            <version>0.1.0</version>
        </Namespace_Module>
    </modules>
      <global>
        <helpers>
            <namespace_module>
                <class>Namespace_Module_Helper</class>
            </namespace_module>
        </helpers>
    </global>
</config>

Data.php

<!-- local/Namespace/MyModule/Helper/Data.php -->
<?php

class Namespace_Module_Helper_Data extends Mage_core_Helper_Abstract {
  
  public function isActivated 
  {
    return Mage::getStoreConfig('namespace_module/active_picture');
  }
  
  public function getPictures 
  {
    $isActived = $this->isActivated;
    if($isActived)
    {
      /** adapt $i with your number picture_push**/
        for ($i = 1; $i < 2; $i++) 
        {
            $pictures[] = Mage::getStoreConfig("namespace_module/picture_push$i")["image"];
        }
        return $pictures;
    }
  }
}

system.xml

<!-- local/Namespace/MyModule/etc/system.xml -->
<?xml version="1.0" encoding="utf-8" ?>
<config>
  <!-- define tabs in system configuration -->
    <tabs>
        <my_tabs translate="label" module="namespace_module">
            <label>My Tabs Label</label>
            <sort_order>0</sort_order>
        </my_tabs>
    </tabs>
  <!-- define section in this tab -->  
    <sections>
        <namespace_module translate="label" module="namespace_module">
            <label>My Custom Label</label>
            <tab>my_tabs</tab>
            <frontend_type>text</frontend_type>
            <sort_order>100</sort_order>
            <show_in_default>1</show_in_default>
            <show_in_website>1</show_in_website>
            <show_in_store>1</show_in_store>
  <!-- define groups in this section , for each group we define fields  -->          
            <groups>
                <active_picture translate="label" module="namespace_module">
                    <label>Pictures Management</label>
                    <frontend_type>text</frontend_type>
                    <sort_order>0</sort_order>
                    <show_in_default>1</show_in_default>
                    <show_in_website>1</show_in_website>
                    <show_in_store>1</show_in_store>
                    <fields>
                        <use_picture translate="label comment">
                            <label>Activate pictures</label>
                            <comment>Pictures will be visible in frontend</comment>
                            <frontend_type>select</frontend_type>
                            <source_model>adminhtml/system_config_source_yesno</source_model>
                            <sort_order>10</sort_order>
                            <show_in_default>1</show_in_default>
                            <show_in_website>1</show_in_website>
                            <show_in_store>1</show_in_store>
                        </use_picture>
                    </fields>
                </active_picture>
                <picture_push1 translate="label" module="namespace_module">
                    <label>Image : Push 1</label>
                    <frontend_type>text</frontend_type>
                    <sort_order>10</sort_order>
                    <show_in_default>1</show_in_default>
                    <show_in_website>1</show_in_website>
                    <show_in_store>1</show_in_store>
                    <fields>
                        <image translate="label comment">
                            <label>Image</label>
                            <frontend_type>image</frontend_type>
                            <backend_model>adminhtml/system_config_backend_image</backend_model>
                            <upload_dir config="system/filesystem/media" scope_info="1">my_custom_folder</upload_dir>
                            <base_url type="media" scope_info="1">my_custom_folder</base_url>
                            <sort_order>10</sort_order>
                            <show_in_default>1</show_in_default>
                            <show_in_website>1</show_in_website>
                            <show_in_store>1</show_in_store>
                        </image>
                    </fields>
                </picture_push1>
                <picture_push2 translate="label" module="namespace_module">
                    <label>Image : Push 2</label>
                    <frontend_type>text</frontend_type>
                    <sort_order>20</sort_order>
                    <show_in_default>1</show_in_default>
                    <show_in_website>1</show_in_website>
                    <show_in_store>1</show_in_store>
                    <fields>
                        <image translate="label comment">
                            <label>Image</label>
                            <frontend_type>image</frontend_type>
                            <backend_model>adminhtml/system_config_backend_image</backend_model>
                            <upload_dir config="system/filesystem/media" scope_info="1">my_custom_folder</upload_dir>
                            <base_url type="media" scope_info="1">my_custom_folder</base_url>
                            <sort_order>20</sort_order>
                            <show_in_default>1</show_in_default>
                            <show_in_website>1</show_in_website>
                            <show_in_store>1</show_in_store>
                        </image>
                    </fields>
                </picture_push2>
            </groups>
        </namespace_module>
    </sections>
</config>