Magento – Magento 2 : Added field for image upload in admin form

I have followed Magento2 : Admin module Image upload code to display form

to add a field for image upload , now getting an error

Fatal error: Class 'vendor\modulename\Controller\Adminhtml\modulename\LocalizedException' not found in /var/www/html/label/app/code/vendor/modulename/Controller/Adminhtml/modulename/Save.php on line 60

How to solve this ? Please help me to resolve this..
save.php

<?php
/**
 * Copyright © 2016 AionNext Ltd. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace vendor\modulename\Controller\Adminhtml\modulename;

use Magento\Framework\App\Filesystem\DirectoryList;

class Save extends \vendor\modulename\Controller\Adminhtml\modulename
{
    protected $_fileUploaderFactory;
    /**
    * @var \Magento\Framework\Filesystem
    */
    protected $filesystem;

    /**
     * @var \Magento\Backend\Helper\Js
     */
    protected $_jsHelper;

    public function __construct(
        \Magento\Backend\App\Action\Context $context,
        \Magento\Backend\Helper\Js $jsHelper,
        \Magento\MediaStorage\Model\File\UploaderFactory $fileUploaderFactory,
        \Magento\Framework\Filesystem $filesystem,
        \Magento\Framework\Registry $coreRegistry
    )
    {
        $this->_jsHelper = $jsHelper;       
        $this->_fileUploaderFactory = $fileUploaderFactory;
        $this->filesystem = $filesystem;
        parent::__construct($context,$coreRegistry);
    }   

    /**
     * Image upload
     *
     * @return string
     */
    public function uploadFileAndGetName($input, $destinationFolder, $data)
    {
        try {  
            $media = $this->filesystem->getDirectoryRead(DirectoryList::MEDIA);
            if (isset($data[$input]['delete'])) {
                unlink($media->getAbsolutePath($data[$input]['value']));
            }

            $uploader = $this->_fileUploaderFactory->create(['fileId' => $input]);
            $uploader->setAllowRenameFiles(true);
            $uploader->setFilesDispersion(true);
            $uploader->setAllowCreateFolders(true);
            $path = $media->getAbsolutePath($destinationFolder);
            $result = $uploader->save($path);
            return $destinationFolder.$result['file'];

        } catch (\Exception $e) {
            if ($e->getCode() != \Magento\Framework\File\Uploader::TMP_NAME_EMPTY) {
                throw new LocalizedException($e->getMessage());
            } else {
                if (isset($data[$input]['value'])) {
                    return $data[$input]['value'];
                }
            }
        }
        return '';
    }

    /**
     * Save action
     *
     * @return \Magento\Framework\Controller\ResultInterface
     */
    public function execute()
    {
        /** @var \Magento\Backend\Model\View\Result\Redirect $resultRedirect */
        $resultRedirect = $this->resultRedirectFactory->create();
        // check if data sent
        $data = $this->getRequest()->getPostValue();
        if ($data) { 
            $id = $this->getRequest()->getParam('label_id');
            $model = $this->_objectManager->create('vendor\modulename\Model\modulename')->load($id);
            if (!$model->getId() && $id) {
                $this->messageManager->addError(__('This item no longer exists.'));
                return $resultRedirect->setPath('*/*/');
            }


            // get image file name 
            $result = \vendor\modulename\Model\modulename::BASE_MEDIA_PATH;
            $pdtimageName = $this->uploadFileAndGetName('product_label', $result, $data);
            $catimageName = $this->uploadFileAndGetName('category_label', $result, $data);
            $data['product_label']=$pdtimageName;
            $data['category_label']=$catimageName;       
            // init model and set data

            $model->setData($data);

            // try to save it
            try {

                // save the data
                $model->save();
                $this->saveProducts($model, $data);
                // display success message
                $this->messageManager->addSuccess(__('You saved the item.'));
                // clear previously saved data from session
                $this->_objectManager->get('Magento\Backend\Model\Session')->setFormData(false);

                // check if 'Save and Continue'
                if ($this->getRequest()->getParam('back')) {
                    return $resultRedirect->setPath('*/*/edit', ['label_id' => $model->getId()]);
                }
                // go to grid
                return $resultRedirect->setPath('*/*/');
            } catch (\Exception $e) {
                // display error message
                $this->messageManager->addError($e->getMessage());
                // save data in session
                $this->_objectManager->get('Magento\Backend\Model\Session')->setFormData($data);
                // redirect to edit form
                return $resultRedirect->setPath('*/*/edit', ['label_id' => $this->getRequest()->getParam('label_id')]);
            }
        }
        return $resultRedirect->setPath('*/*/');
    }

    public function saveProducts($model, $post)
    {   
        // Attach the attachments to contact
        if (isset($post['products'])) {
            $productIds = $this->_jsHelper->decodeGridSerializedInput($post['products']); 
            try {
                $oldProducts = (array) $model->getProducts($model);
                $newProducts = (array) $productIds;

                $this->_resources = \Magento\Framework\App\ObjectManager::getInstance()->get('Magento\Framework\App\ResourceConnection');
                $connection = $this->_resources->getConnection();

                $table = $this->_resources->getTableName(\vendor\modulename\Model\ResourceModel\modulename::TBL_ATT_PRODUCT);
                $insert = array_diff($newProducts, $oldProducts);
                $delete = array_diff($oldProducts, $newProducts);

                if ($delete) {
                    $where = ['label_id = ?' => (int)$model->getId(), 'product_id IN (?)' => $delete];
                    $connection->delete($table, $where);
                }

                if ($insert) {
                    $data = [];
                    foreach ($insert as $product_id) {
                        $data[] = ['label_id' => (int)$model->getId(), 'product_id' => (int)$product_id];
                    }
                    $connection->insertMultiple($table, $data);
                }
            } catch (Exception $e) {
                $this->messageManager->addException($e, __('Something went wrong while saving the label.'));
            }
        }

    }

}

THis is my form code for image fields:

   protected function _prepareForm()
    {
        /* @var $model \vendor\Productlabel\Model\Productlabel */
        $model = $this->_coreRegistry->registry('productlabel_item');

        /** @var \Magento\Framework\Data\Form $form */
        $form = $this->_formFactory->create(
            array(
                'data' => array(
                    'id'        => 'edit_form',
                    'action'    => $this->getData('action'),
                    'method'    => 'post',
                    'enctype'   => 'multipart/form-data',
                ),
            )
        );

        $form->setHtmlIdPrefix('label_');

        $fieldset = $form->addFieldset('base_fieldset', ['legend' => __('Product Label Information')]);

        if ($model->getId()) {
            $fieldset->addField('label_id', 'hidden', ['name' => 'label_id']);
        }

        $fieldset->addField(
            'title',
            'text',
            array(
                'name' => 'title',
                'label' => __('Title'),
                'title' => __('Title'),
                'required' => true
            )
        );

        $fieldset->addField(
            'status',
            'select',
            array(
                'label' => __('Status'),
                'title' => __('Status'),
                'name' => 'status',
                'required' => true,
                'options' => ['1' => __('Enabled'), '0' => __('Disabled')]
           )
        );
        if (!$model->getId()) {
            $model->setData('status', '1');
        }

        $fieldset->addField(
            'product_label',
            'image',
            array(
                'name' => 'product_label',
                'label' => __('Product Label'),
                'title' => __('Product Label'),
                'note' => 'Allow image type: jpg, jpeg, gif, png',
           )
        );

        $fieldset->addField(
            'category_label',
            'image',
            array(
                'name' => 'category_label',
                'label' => __('Category Label'),
                'title' => __('Category Label'),
                'required' => false,
                'note' => 'Allow image type: jpg, jpeg, gif, png',
            )
        );

        $form->setValues($model->getData());
        $this->setForm($form);

        return parent::_prepareForm();
    }