Build your own Generator

Implement your own generator

To implement your own Generator, first check the code of the Generators included in the Media package.

Basically, you need to extend AbstractThumbnailGenerator and implement the ThumbnailGeneratorInterface::refresh() method. The refresh method receives a Thumbnail object, based on this object do the required processing to generate a thumbnail. In most cases the Thumbnail can be persisted by attaching the new resource to the Thumbnail object.

Determine if a Generator can handle the current Thumbnail

You can also implement the ThumbnailGeneratorInterface::canRefresh() if your Generator has some specific requirements (like maximum file size, MIME type, external service availability, etc.).


The ThumbnailGeneratorStrategy choose the Generator by two factors, the value of the static property priority and the return value of the method ThumbnailGeneratorInterface::canRefresh(). For priority value, higher is better:

class YourOwnThumbnailGenerator extends AbstractThumbnailGenerator
     * @var integer
     * @api
    protected static $priority = 100;

You can always override this priority in your Settings.yaml.


In your generator class use the AbstractThumbnailGenerator::getOption() to access your settings:

        priority: 100
        parameterOne: 100
        parameterTwo: 200

Remember to add the Media Package in your package composer.json` to load the Media package before your own:

    "require": {
        "neos/flow": "*",
        "neos/media": "*"

Community supported Generators

  • FilePreviews

    Can be use to integrate the service from in your project and generate thumbnail for Office or Audio documents.

Feel free to contact us at, if you publish some Generators under an open-source licence.