I found solution using this script,
In above condition, product image are already assign in database but not show in frontend, you can do this using this script.
You need to do following things,
Create one file in magento root directories, let say file name is "Productimage.php"
Put the following code into that file,
<?php
use Magento\Framework\App\Bootstrap;
require __DIR__ . '/app/bootstrap.php';
$bootstrap = Bootstrap::create(BP, $_SERVER);
$obj = $bootstrap->getObjectManager();
$state = $obj->get('Magento\Framework\App\State');
$state->setAreaCode('frontend');
try
{
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();
$importDir = __DIR__ . '/pub/media/catalog/product';
$product = $objectManager->get('Magento\Catalog\Model\Product')->load(YOURPRODUCTID);
if($product->getImage() != '')
{
$id = $product->getId();
$url = $importDir . $product->getImage();
$product->addImageToMediaGallery($url, array('image', 'small_image', 'thumbnail'), true, false);
$product->save();
echo "<br /><br /> $id Product Save Succefully";
}
}
catch(\Exception $e)
{
echo $e->getMessage();
exit;
}
NOTE: replace YOURPRODUCTID with your real Id.
.htaccess
as well