src/Gallery.php
public function addImage(Image $image)
    {
        if (!isset($this->images[$image->getId()])) {
            $this->count++;
        }
        $this->images[$image->getId()] = $image;

        return $this;
    }
public function addImage(Image $image)
    {
        if (!isset($this->images[$image->getId()])) {
            $this->count++;
        }
        $this->images[$image->getId()] = $image;

        return $this;
    }
add Image

@param Image $image
@return $this