GdThumb::verifyFormatCompatiblity PHP Method

    protected function verifyFormatCompatiblity()
    {
        $isCompatible = true;
        $gdInfo = gd_info();
        switch ($this->format) {
            case 'GIF':
                $isCompatible = $gdInfo['GIF Create Support'];
                break;
            case 'JPG':
                $isCompatible = isset($gdInfo['JPG Support']) || isset($gdInfo['JPEG Support']) ? true : false;
                break;
            case 'PNG':
                $isCompatible = $gdInfo[$this->format . ' Support'];
                break;
            default:
                $isCompatible = false;
        }
        if (!$isCompatible) {
            // one last check for "JPEG" instead
            $isCompatible = $gdInfo['JPEG Support'];
            if (!$isCompatible) {
                $this->triggerError('Your GD installation does not support ' . $this->format . ' image types');
            }
        }
    }