Add Resizing to Image Upload code

[jnscollier]

Hey all,
So I have a form that allows users to upload pictures. When they upload the picture (I found this handy script) that renames the file to a bunch of numbers and stores it in my Upload folder. Then I use javascript on the display page to dynamically resize the picture proportionally.... Well, I'm starting to not like this because you can see the picture look all huge one second and like 2 seconds later it scales down. So I'm wondering, is there any way to modify the upload picture script so that it automatically resizes the actual file? That way I don't have to resize it on the display page. Basically I want the picture uploaded to be no larger than 500 px (either width/height depending on what side is larger)....

My php code for the image upload part



<?php
//define a maxim size for the uploaded images in Kb
define ("MAX_SIZE","400");

//This function reads the extension of the file. It is used to determine if the file is an image by checking the extension.
function getExtension($str) {
$i = strrpos($str,".");
if (!$i) { return ""; }
$l = strlen($str) - $i;
$ext = substr($str,$i+1,$l);
return $ext;
}

//This variable is used as a flag. The value is initialized with 0 (meaning no error found) and it will be changed to 1 if an error occures. If the error occures the file will not be uploaded.
$errors=0;
//checks if the form has been submitted
if(isset($_POST['Submit']))
{
//reads the name of the file the user submitted for uploading
$image=$_FILES['image']['name'];
//if it is not empty
if ($image)
{
//get the original name of the file from the clients machine
$filename = stripslashes($_FILES['image']['name']);

//get the extension of the file in a lower case format
$extension = getExtension($filename);
$extension = strtolower($extension);

//if it is not a known extension, we will suppose it is an error and will not upload the file, otherwize we will do more tests
if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png") && ($extension != "gif"))
{
//print error message
$verybad = "err1";
header("Location:geti.php?image=$verybad");
$errors=1;
}
else
{
//get the size of the image in bytes
//$_FILES['image']['tmp_name'] is the temporary filename of the file in which the uploaded file was stored on the server
$size=filesize($_FILES['image']['tmp_name']);

//compare the size with the maxim size we defined and print error if bigger
if ($size > MAX_SIZE*1024)
{
$verybad = "err2";
header("Location:geti.php?image=$verybad");
$errors=1;
}

//we will give an unique name, for example the time in unix time format
$image_name=time().'.'.$extension;
//the new name will be containing the full path where will be stored (images folder)
$newname="upload/".$image_name;

//we verify if the image has been uploaded, and print error instead
$copied = copy($_FILES['image']['tmp_name'], $newname);
if (!$copied)
{
$verybad = "err3";
header("Location:geti.php?image=$verybad");
$errors=1;
}}}}

//If no errors registred, print the success message
if(isset($_POST['Submit']) && !$errors)
{
echo "";
}

?>


Can anyone help me? I would greatly appreciate it! Thanks so much!
-Sammy

[djr33]

http://php.net/manual/en/function.imagecopyresampled.php

just apply that to the image. Look at the examples for some usable code. The second should apply.

[jnscollier]

Maybe I'm not doing this right.... I'm not sure.... What I would like is for the image itself to be resized so I don't have to resize it on the display pages (like reduce the actual image size). I tried the second example and on the test page ... it reduced it, but when i went and viewed the actual image file it was still it's original size. I don't know if i'm making sense or if i just didn't do something right. The example I tried was:




<?php
// The file
$filename = 'test.jpg';

// Set a maximum height and width
$width = 200;
$height = 200;

// Content type
header('Content-type: image/jpeg');

// Get new dimensions
list($width_orig, $height_orig) = getimagesize($filename);

$ratio_orig = $width_orig/$height_orig;

if ($width/$height > $ratio_orig) {
$width = $height*$ratio_orig;
} else {
$height = $width/$ratio_orig;
}

// Resample
$image_p = imagecreatetruecolor($width, $height);
$image = imagecreatefromjpeg($filename);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height, $width_orig, $height_orig);

// Output
imagejpeg($image_p, null, 100);
?>



Also, I want it to do this for jpg, png, and gif.... I noticed this only does it for jpg... is there a more universal code??

Thanks in advance!

[djr33]

imagejpeg($image_p, null, 100);
will just output the file. Using a path/filename instead of null will save it to that location (and not output the image directly).

As for the different filetypes, it's not that hard, just tedious. Use if statements. if you can determine the type some way, then just use that type and pick the function (imagecreatefromgif, etc.), or use if statements which will be slightly slower:
if ($im = imagecreatefromgif(...)) {...
else if ...jpeg
else if ...png
else [error]

Also, if you want to use bmp, google "imagecreatefrombmp" and you'll find a script that will do it.


By the way, you may want to standardize the output format, probably to jpeg.