function Valida(formulario)
  {
  if ((formulario.nombre.value == '') || (formulario.empresa.value == '') || (formulario.email.value == '') || (formulario.consulta.value == ''))
  {
	alert("Debe completar todos los campos del formulario");
    return false;
  }
  else
  {
    formulario.submit();
  }
}

function changeImage(filename,boton_activo,cantidad)
{
var image1 = new Image();
var image2 = new Image();
var image3 = new Image();
var image4 = new Image();
var image5 = new Image();
var image6 = new Image();
var image7 = new Image();
var image8 = new Image();
var image9 = new Image();
var mainimage = new Image();
var i;

for (i=cantidad;i > 0;i--)
{
document.images["image"+i].src = "./imagenes/botones_numeros_fotos/" + i + ".jpg";
}

for (i=cantidad;i > 0;i--)
{
if (boton_activo == 1){
document.images["image1"].src = "./imagenes/botones_numeros_fotos/1_click.jpg";}
else if (boton_activo == 2){
document.images["image2"].src = "./imagenes/botones_numeros_fotos/2_click.jpg";}
else if (boton_activo == 3){
document.images["image3"].src = "./imagenes/botones_numeros_fotos/3_click.jpg";}
else if (boton_activo == 4){
document.images["image4"].src = "./imagenes/botones_numeros_fotos/4_click.jpg";}
else if (boton_activo == 5){
document.images["image5"].src = "./imagenes/botones_numeros_fotos/5_click.jpg";}
else if (boton_activo == 6){
document.images["image6"].src = "./imagenes/botones_numeros_fotos/6_click.jpg";}
else if (boton_activo == 7){
document.images["image7"].src = "./imagenes/botones_numeros_fotos/7_click.jpg";}
else if (boton_activo == 8){
document.images["image8"].src = "./imagenes/botones_numeros_fotos/8_click.jpg";}
else if (boton_activo == 9){
document.images["image9"].src = "./imagenes/botones_numeros_fotos/9_click.jpg";}
}
document.images["mainimage"].src = filename;
}