I'd say that the best way to do this is to make PHP scripts that read a directory on the server and pick a random image in the list and you display it.
Be carefull with this method cause if you use a lot of images and the page is requested a lot, it might cause performance problem with the server.
Use this PHP function to get a random image and use the output in your HTML file.
// ===========================================================================
// | NOM : randomImage
// | ENTRÉES : $dirName - Path to the image directory.
// | SORTIES : None - (except return)
// | RETOUR : $result - Name of the random file selected.
// |
// | DESCRIPTION : Select a random image from a directory. Please note that
// | this function only works with *.jpg for the moment.
// ===========================================================================
function randomImage( $dirName )
{
// Open the directory
$cursor = opendir($dirName);
// List all the random images
$counter = 0;
while( false !== ( $file = readdir( $cursor ) ))
{
$allfile[ $counter ] = $file;
// DEBUG
// echo "<p>File ".$counter." ".$file."</p>";
$counter ++;
}
// Select the randon image
// Remove . and ..
// Verification to check if it is a valid image file
$result = "not-an-image";
while( !strstr( $result, ".jpg" ))
{
$min = 2;
$max = $counter - 1 ;
srand( (double) microtime() * 1000000 );
$posImage = rand( $min, $max );
$result = $allfile[ $posImage ];
}
// Fermeture du repertoire
closedir( $cursor );
return $result;
}
// === END - randomImage ===
<?php require_once("path-to-php-file-that-have-the-function"); ?>
<html>
<?php
$img = randomImage( "path-to-the-dir-with-images" );
echo '<IMG SRC="path-to-the-dir-with-images/'.$nomImage2.'">'; ?>
</html>
Ok, i've wrap this up really quickly and might have some small errors. I don't know if you know php and if it help but here it is.
The main advantage of this is that you only have to add/remove images from the directory and it still works, no need to edit the code!
TapaGeuR