Per tutti i parametri:
https://google-developers.appspot.com/chart/infographics/docs/qr_codes (https://google-developers.appspot.com/chart/infographics/docs/qr_codes)
esempio: http://chart.apis.google.com/chart?cht=qr&chs=150x150&chl=http://www.altrove.info (http://chart.apis.google.com/chart?cht=qr&chs=150x150&chl=http://www.altrove.info)