pictures.php

<?require $_SERVER['DOCUMENT_ROOT'] . '/bitrix/modules/main/include/prolog_before.php';?>

<?
\Bitrix\Main\Loader::includeModule('iblock');

$ar = array();

$arFilter = array(
  'IBLOCK_ID'    => IBLOCK_CAT_ID,
  'ACTIVE'       => 'Y'
);

$res = CIBlockElement::GetList(array('sort' => 'asc'), $arFilter, false, false, array('DETAIL_PICTURE'));

while($ob = $res->GetNext())
{
  $ar[] = CFile::GetPath($ob['DETAIL_PICTURE']);
}

pre($ar);
?>