Contao\GdImage::saveToFile PHP Method

    public function saveToFile($path)
    {
        $arrGdInfo = gd_info();
        $extension = strtolower(substr($path, strrpos($path, '.') + 1));
        // Fallback to PNG if GIF ist not supported
        if ($extension == 'gif' && !$arrGdInfo['GIF Create Support']) {
            $extension = 'png';
        }
        // Get the relative path
        $folder = str_replace(TL_ROOT . '/', '', $path);
        // Create the parent folder
        if (($dirname = dirname($folder)) != '.' && !is_dir(TL_ROOT . '/' . $dirname)) {
            new \Folder($dirname);
        }
        // Create the new image
        switch ($extension) {
            case 'gif':
                $this->convertToPaletteImage();
                imagegif($this->gdResource, $path);
                break;
            case 'jpg':
            case 'jpeg':
                imageinterlace($this->gdResource, 1);
                // see #6529
                imagejpeg($this->gdResource, $path, \System::getContainer()->getParameter('contao.image.imagine_options')['jpeg_quality'] ?: 80);
                break;
            case 'png':
                if ($this->countColors(256) <= 256 && !$this->isSemitransparent()) {
                    $this->convertToPaletteImage();
                }
                imagepng($this->gdResource, $path);
                break;
            default:
                throw new \InvalidArgumentException('Image type "' . $extension . '" cannot be generated');
                break;
        }
        return $this;
    }