Storyblok has an image transformation service that allows you to resize, crop and convert image formats and we make it really easy to use.
All Storyblok Asset fields with uploaded images are automatically converted into Image Field classes. These can be transformed by calling transform() and chaining the various methods.
// $image = Riclep\Storyblok\Fields\Image or any class extending it
// scales and crops the image to the requested dimensions (width, height, [focus]). If the proportions differ from the original image it is cropped
$image->transform()->resize(234, 432);
// scales the image and crops centering on the ‘focal point’ specified on the image in Storyblok
$image->transform()->resize(234, 432, 'focus');
// scales the image and crops using Storyblok’s Smart Crop feature for detecting faces
$image->transform()->resize(234, 432, 'smart');
// scales the image to fit inside the dimensions and set the background colour (width, height, [background colour]),
$image->transform()->fitIn(400, 300, 'ff0000');
// fits the image and adds a transparent background, or fitIn(400, 700, 'transparent'). The file is converted a .png
$image->transform()->fitIn(400, 700);
// converts the image to the supplied format (jpeg, png, webp)
$image->transform()->format('webp');
// convert the image to a jpg with a quality of 30
$image->transform()->format('jpeg', 30);{info} When converting the file format the URL retains the original file extension. Not all browsers support webp yet!
Transformations can be chained but not all combinations will work well together such as using fitIn() with a transparent background and converting a jpeg as this format doesn’t support transparency.
$image->transform()->resize(800, 450)->format('webp');Rather than defining your transformations every time you use them they can be added directly to an Image class as follows. Make a class extending Riclep\Storyblok\Fields\Image and define a transformations() method that sets the transformations property. This property should be an array of named arrays with two keys: src - a transformation and media - a <picture> element media string (this can be left empty). Each outer array is the name of the transformation, an example will make it clearer.
Here we define two image sizes, ‘mobile’ and ‘desktop’. The desktop variant includes a media query.
namespace App\Storyblok\Fields;
use Riclep\Storyblok\Fields\Image;
class HeroImage extends Image
{
protected function transformations() {
$this->transformations = [
'desktop' => [
'src' => $this->transform()->resize(500, 400),
'media' => '(min-width: 1000px)',
],
'mobile' => [
'src' => $this->transform()->resize(100, 120)->format('webp'),
'media' => '',
],
];
}
}They can now be accessed by name returning the ImageTransform object exactly like the manual transformations above and will return the image URL when cast to a string.
$image->transform('mobile');
$image->transform('desktop');We didn’t use the media key in the previous example; that’s because it’s used for creating <picture> elements! To create a picture element make sure you define your transformations and call the picture($alt) method including the alt text you wish to use.
$image->picture('Some alt text');This will create the following picture element with two <source> tags. The <img> tag will use the original, non-transformed image from Storyblok.
<picture>
<source srcset="//img2.storyblok.com/100x120/filters:format(webp)/f/87028/960x1280/31a1d8dc75/an-image.jpg" type="image/webp" media="">
<source srcset="//img2.storyblok.com/500x400/f/87028/960x1280/31a1d8dc75/an-image.jpg" type="image/jpeg" media="(min-width: 1200px)">
<img src="https://a.storyblok.com/f/87028/960x1280/31a1d8dc75/an-image.jpg" alt="Some alt text">
</picture>{warning} The order you define the transformations is important and is the order they will appear in your html. Web browsers will use the first
<source>tag they find that matches the media query!
You can set the transformation to use for the <img> tag by passing it’s name as the second argument.
$image->picture('A super image', 'mobile');<picture>
<source srcset="//img2.storyblok.com/500x400/f/87028/960x1280/31a1d8dc75/an-image.jpg" type="image/jpeg" media="(min-width: 1200px)">
<img src="//img2.storyblok.com/100x120/filters:format(webp)/f/87028/960x1280/31a1d8dc75/an-image.jpg" alt="A super image">
</picture>You can add additional attributes to the <img> tag with the third argument with takes a key-value pair of attribute-value.
$image->picture('A super image', 'mobile', ['class' => 'hero mb-10', 'id' => 'hero-image']);If you don’t like the default view used for generating the <picture> element then you can supply your own Blade view with the forth argument
$image->picture('A super image', 'mobile', ['class' => 'hero mb-10', 'id' => 'hero-image'], 'blocks.picture');
// the view receives the following data
[
'alt' => $alt, // A super image
'attributes' => $attributes, // ['class' => 'hero mb-10', 'id' => 'hero-image']
'default' => $default, // mobile
'imgSrc' => $imgSrc, // URL of the default image
'transformations' => $this->transformations, // array of $image->transformations
];{info} When supplying your own view you could add extra items to the
transformationsarray to use on each image size.
Finally, for full control just override the picture() method on your custom Image class.
Image transformations implement __toString() and will be converted into a Storyblok Image Service URL when used in Blade etc.
You can make a custom transformation by calling $image->transform()->createUrl($options). The $options argument should be a valid URL parameter such as /fit-in/200x200/filters:fill(CCCCCC).
Every Image contains meta data that may be useful.
// dimensions in pixels
$image->width();
$image->height();
// returns the mimetype
$image->type();