Pimcore\Model\Object\ClassDefinition\Data\Image::getCacheTags PHP Method

    public function getCacheTags($data, $tags = [])
    {
        $tags = is_array($tags) ? $tags : [];
        if ($data instanceof Asset\Image) {
            if (!array_key_exists($data->getCacheTag(), $tags)) {
                $tags = $data->getCacheTags($tags);
            }
        }
        return $tags;
    }