How to resize image in magento 2

storeManager = $context->getStoreManager();
        $this->imageFactory = $imageFactory;
        $this->_filesystem = $filesystem;
        $this->_directory = $filesystem->getDirectoryWrite(DirectoryList::MEDIA);
        parent::__construct(
            $context,
            $data
        );
    }

    /**
     * @param $imageName string imagename only(abc.jpg)
     * @param $width int
     * @param $height int
     * @return string
     */
    public function getResizeImage($imageName,$width = 258,$height = 200)
    {
        /* Real path of image from directory */
        $realPath = $this->_filesystem->getDirectoryRead(DirectoryList::MEDIA)->getAbsolutePath('catalog/category/'.$imageName);
        if (!$this->_directory->isFile($realPath) || !$this->_directory->isExist($realPath)) {
            return false;
        }
        /* Target directory path where our resized image will be save */
        $targetDir = $this->_filesystem->getDirectoryRead(DirectoryList::MEDIA)->getAbsolutePath('resized/'.$width.'x'.$height);
        $pathTargetDir = $this->_directory->getRelativePath($targetDir);
        /* If Directory not available, create it */
        if (!$this->_directory->isExist($pathTargetDir)) {
            $this->_directory->create($pathTargetDir);
        }
        if (!$this->_directory->isExist($pathTargetDir)) {
            return false;
        }

        $image = $this->imageFactory->create();
        $image->open($realPath);
        $image->keepAspectRatio(true);
        $image->resize($width,$height);
        $dest = $targetDir . '/' . pathinfo($realPath, PATHINFO_BASENAME);
        $image->save($dest);
        if ($this->_directory->isFile($this->_directory->getRelativePath($dest))) {
            return $this->storeManager->getStore()->getBaseUrl(\Magento\Framework\UrlInterface::URL_TYPE_MEDIA).'resized/'.$width.'x'.$height.'/'.$imageName;
        }
        return false;
    }
}