public static function getQrCodeUrl($type, $label, $secret, $counter = null, $options = array())
    {
        // Width and height can be overwritten
        $width = self::$width;

        if (array_key_exists('width', $options) && is_numeric($options['width'])) {
            $width = $options['width'];
        }

        $height = self::$height;

        if (array_key_exists('height', $options) && is_numeric($options['height'])) {
            $height = $options['height'];
        }

        $otpauth = self::getKeyUri($type, $label, $secret, $counter, $options);

        $url = 'https://chart.googleapis.com/chart?chs=' . $width . 'x'
             . $height . '&cht=qr&chld=M|0&chl=' . urlencode($otpauth);

        return $url;
    }
public static function getQrCodeUrl($type, $label, $secret, $counter = null, $options = array())
    {
        // Width and height can be overwritten
        $width = self::$width;

        if (array_key_exists('width', $options) && is_numeric($options['width'])) {
            $width = $options['width'];
        }

        $height = self::$height;

        if (array_key_exists('height', $options) && is_numeric($options['height'])) {
            $height = $options['height'];
        }

        $otpauth = self::getKeyUri($type, $label, $secret, $counter, $options);

        $url = 'https://chart.googleapis.com/chart?chs=' . $width . 'x'
             . $height . '&cht=qr&chld=M|0&chl=' . urlencode($otpauth);

        return $url;
    }
public static function getQrCodeUrl ( $ type , $ label , $ secret , $ counter = null , $ options = array ( ) ) { // Width and height can be overwritten $ width = self :: $ width ; if ( array_key_exists ( 'width' , $ options ) && is_numeric ( $ options [ 'width' ] ) ) { $ width = $ options [ 'width' ] ; } $ height = self :: $ height ; if ( array_key_exists ( 'height' , $ options ) && is_numeric ( $ options [ 'height' ] ) ) { $ height = $ options [ 'height' ] ; } $ otpauth = self :: getKeyUri ( $ type , $ label , $ secret , $ counter , $ options ) ; $ url = 'https://chart.googleapis.com/chart?chs=' . $ width . 'x' . $ height . '&cht=qr&chld=M|0&chl=' . urlencode ( $ otpauth ) ; return $ url ; }
Returns the QR code url

Format of encoded url is here:
https://code.google.com/p/google-authenticator/wiki/KeyUriFormat
Should be done in a better fashion

@param string $type totp or hotp
@param string $label Label to display this as to the user
@param string $secret Base32 encoded secret
@param integer $counter Required by hotp, otherwise ignored
@param array $options Optional fields that will be set if present

@return string URL to the QR code
Returns the QR code url