function graypic_on (cpic_id) {


 if (document.getElementById(cpic_id).name == "leer") {
  grayscale(document.getElementById(cpic_id));
  document.getElementById(cpic_id).name = "gray";
 }

}



function Gray_PC (cpic_id) {
  grayscale(document.getElementById(cpic_id));
  document.getElementById(cpic_id).name = "gray";
}


function Color_PC (cpicname) {

 var el = document.getElementById(cpicname );
 grayscale.reset( el );
}