function extract_post_images( $post, $w, $h ) {
$posttext = $post->post_content;
$posttext1 = $post->post_content;

$regular_expression = ‘~src=”[^"]*”~’;
$regular_expression1 = ‘~]*\ />~’;
$regular_expression3 = ‘~caption=”[^"]*”~’;

preg_match_all( $regular_expression3, $posttext, $allcaptions );
preg_match_all( $regular_expression, $posttext, $allpics );

$NumberOfPics = count($allpics[0]);

if ( $NumberOfPics > 0 ) {
for ( $i=0; $i < $NumberOfPics ; $i++ ) {
// hack the img url about
$str1=$allpics[0][$i];
$str1=trim($str1);
$len=strlen($str1);
$imgpath=substr_replace(substr($str1,5,$len),"",-1);

// hack the image caption about
$str2=$allcaptions[0][$i];
$str2=trim($str2);
$len2=strlen($str2);
$caption=substr_replace(substr($str2,9,$len2),"",-1);

echo '’;
echo ‘ ‘.$caption.”;
echo ”;
}
}
}

code I’m using currently:

get_the_ID(), ‘post_type’ => ‘attachment’, ‘post_mime_type’ => ‘image’) );
foreach ( $attachments as $attachment_id => $attachment ) {
echo ”;
echo ‘ ‘ . wp_get_attachment_link( $attachment_id ) . ”;
echo ”;
} ?>

It is very old article. Yes the text get messes up. From wordpress 2.9 new feature is added to the wordpress. the_post_thumbnail() which you can use add the thumbnail to your post. you can check more details about it at WordPress 2.9 the post thumbnail