Magento 2 resize category & product image

Question

I want to resize category & product images for custom widget and I prefer Magento default function so I found following code to do so but I think it's for Magento 1

$imageObj = new Varien_Image ( $imageUrl );
$imageObj=$imageObj->constrainOnly ( true )
->keepAspectRatio ( true )
->keepFrame ( false )
->quality ( $quality )
->resize ( $width, $height )
->save ( $imageResized );

So I wish to know that does Magento 2 provide any function to resize,crop,scale any images including category,product etc.??

Answer 1

You can get all image related methods for category and product from helper file inside Magento_Catalog module core file,

vendor/magento/module-catalog/Helper/Image.php

List of methods are

• resize()

• List item

• keepAspectRatio()

• setQuality()
• keepFrame()

• keepTransparency()

  $_imagehelper = $this->helper('Magento\Catalog\Helper\Image');

<img src="<?php echo $_imagehelper->init($_product, 'thumbnail')->keepAspectRatio(true)->resize('400', '400'); ?>" />

this is to use in version 2.2. the image type was changed

<img src="<?php echo $_imagehelper->init($_product, 'product_base_image')->keepAspectRatio(true)->resize('400', '400'); ?>" />

For custom Image Resize section

Inside Block file,

protected $_filesystem ;
   protected $_imageFactory;
   public function __construct(            
        \Magento\Framework\Filesystem $filesystem,         
        \Magento\Framework\Image\AdapterFactory $imageFactory ,
        \Magento\Store\Model\StoreManagerInterface $storeManager,       
        ) {         
        $this->_filesystem = $filesystem;               
        $this->_imageFactory = $imageFactory; 
           $this->storeManager = $storeManager;        
        }

    // pass imagename, width and height
    public function resize($image, $width = null, $height = null)
    {
        $absolutePath = $this->_filesystem->getDirectoryRead(\Magento\Framework\App\Filesystem\DirectoryList::MEDIA)->getAbsolutePath('custom_module/posts/').$image;

        $imageResized = $this->_filesystem->getDirectoryRead(\Magento\Framework\App\Filesystem\DirectoryList::MEDIA)->getAbsolutePath('resized/'.$width.'/').$image;         
        //create image factory...
        $imageResize = $this->_imageFactory->create();         
        $imageResize->open($absolutePath);
        $imageResize->constrainOnly(TRUE);         
        $imageResize->keepTransparency(TRUE);         
        $imageResize->keepFrame(FALSE);         
        $imageResize->keepAspectRatio(TRUE);         
        $imageResize->resize($width,$height);  
        //destination folder                
        $destination = $imageResized ;    
        //save image      
        $imageResize->save($destination);         

        $resizedURL = $this->_storeManager->getStore()->getBaseUrl(\Magento\Framework\UrlInterface::URL_TYPE_MEDIA).'resized/'.$width.'/'.$image;
        return $resizedURL;
  } 

Call inside template file $block->resize('img.jpg',300,300);