Este es el upload.php que uso:
Código PHP:
<?php
# DETAILS
$UPLOAD_DIR = 'Alternative/'; # UPLOAD DIRECTORY
$max_width = '499'; # WIDTH TO RESIZE IMAGES ABOVE IT
$max_height = '374'; # HEIGHT TO RESIZE IMAGES ABOVE IT
# DETECT UPLOAD PRESS
if(isset($_POST['upload'])){
# ADD HERE THE CODE FOR ANY OTHER FIELDS YOU MIGHT HAVE
# GET UPLOADED FILES
$photo = $HTTP_POST_FILES['photo'];
foreach($photo['name'] as $file_id => $file){
# IF FILE IS IMAGE
if($file != NULL && (strstr($file, '.jpg') || strstr($file, '.png') || strstr($file, '.gif'))){
# REPLACE QUOTES
$file = str_replace("'", "`", $file);
$file = str_replace('"', '`', $file);
# COMPOSE URL
$url = $UPLOAD_DIR.$file;
# COPY FILE TO URL
if(copy($photo['tmp_name'][$file_id],$url)){
# DELETE TMP FILE
unlink($photo['tmp_name'][$file_id]);
# GET IMAGE DETAILS
$data = GetImageSize($url);
$mime = $data['mime'];
# IF IMAGE IS BIGGER THEN MAX VALUES
if (($data[0] > $max_width) or ($height > $max_height)) {
# IF WIDTH IS BIGGER
if ($data[0] > $max_width) {
$width = $max_width;
$height = $data[1]/($data[0]/$width);
}
# IF HEIGHT IS BIGGER AFTER WIDTH BASED RESIZE
if ($height > $max_height) {
$height = $max_height;
$width = $data[0]/($data[1]/$height);
}
# CRATE NEW IMAGE
$frame = ImageCreateTrueColor($width, $height);
# CRATE FILE IMAGE
if ($mime == 'image/gif') {
$im = ImageCreateFromGIF($url);
} else if ($mime == 'image/png') {
$im = ImageCreateFromPNG($url);
} else if ($mime == 'image/jpeg') {
$im = ImageCreateFromJPEG($url);
}
# RESIZE
imagecopyresized ($frame, $im, 0, 0, 0, 0, $width, $height, $data[0], $data[1]);
# WRITE RESIZED IMAGE
imagejpeg($frame,$url,80);
imagedestroy($frame);
imagedestroy($im);
# ADD HERE THE CODE THAT INSERTS DATA INTO A DATABASE IF YOU WISH
# FILE NAME VARIABLE IS $file
}
}
}
}
}
?>
<form action='' method='post' enctype='multipart/form-data'>
PHOTO 1: <input type=file name=photo[]><br>
PHOTO 2: <input type=file name=photo[]><br>
PHOTO 3: <input type=file name=photo[]><br>
PHOTO 4: <input type=file name=photo[]><br>
PHOTO 5: <input type=file name=photo[]><p>
<input type=submit name=upload value=Upload>
</form> 
