image_type_to_extension gd_info
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Last updated: Mon, 26 Nov 2007
add a note User Contributed Notes
getimagesize
info at alex-lawrence dot com
02-Apr-2008 09:17
Could be useful (didn´t know where to post it):
function getImageErrors( $filename, $type = "", $minWidth = 0, $minHeight = 0, $maxWidth = 0, $maxHeight = 0, $maxFileSize = 0 )
{
$errors = array();
if ( file_exists( $filename ) )
{
$ending = substr( $filename, strpos( $filename, "." ) );
if ( is_array( $type ) )
{
$isTypeOf = false;
foreach( $type as $eachtype )
{
if ( $ending == $eachtype )
{
$isTypeOf = true;
}
}
if ( ! $isTypeOf )
{
$errors[ 'type' ] = $ending;
}
}
elseif ( $type != "" )
{
if ( $ending != $type )
{
$errors[ 'type' ] = $ending;
}
}
$size = getimagesize( $filename );
if ( $size[ 0 ] < $minWidth )
{
$errors[ 'minWidth' ] = $size[ 0 ];
}
if ( $size[ 1 ] < $minHeight )
{
$errors[ 'minHeight' ] = $size[ 1 ];
}
if ( ( $maxWidth > $minWidth ) && ( $size[ 0 ] > $maxWidth ) )
{
$errors[ 'maxWidth' ] = $size[ 0 ];
}
if ( ( $maxHeight > $minHeight ) && ( $size[ 1 ] > $maxHeight ) )
{
$errors[ 'maxHeight' ] = $size[ 1 ];
}
if ( ( $maxFileSize > 0 ) && ( filesize( $filename ) > $maxFileSize ) )
{
$errors[ 'maxFileSize' ] = filesize( $filename );
}
}
else
{
$errors[ 'filename' ] = "not existing";
}
return ( count( $errors ) > 0 ? $errors : null );
}
cloned at clonedmadman dot com
26-Feb-2008 06:01
Well, I am making a script which will resize the image when uploaded, however, i am making a multi-uploader, so i came across with a problem: an efficient way of getting a pictures height and width and storing them in an array to resize later. This is what i came up with:
<?php
$links = array("test1.jpg", "test2.png");
$sizearray = array();
$count = count($links);
for($i = 0; $i < $count; $i++) {
$size = getimagesize($links[$i]);
list($width, $height) = $size;
$sizearray[$links[$i]] = array("width" => $width, "height" => $height);
}
print_r($sizearray);
// which will print out: Array ( [test1.jpg] => Array ( [width] => 300 [height] => 400 ) [test2.png] => Array ( [width] => 680 [height] => 100 ) )
?>
shmohel at gmail dot com
12-Feb-2008 10:27
Rather than making a lengthy function that essentially runs twice (once as width, once as height) I came up with a helpful function that uses variable variables to set a maximum height/width. Hope someone finds this helpful.
return("<img src='{$location}' alt='image' width='{$w}' height='{$h}' />");
}
}
Anonymous
28-Jan-2008 01:14
// A way to maintain Aspect Ratio
// Here using standard aspect ratio of 4:3 for landscape and 3:4 for portrait.
// example is 50% image resize
// here using Image Magick command line utility to resize image, OR you can use some other package.
//@exec("/usr/local/bin/convert $sourceImageFilePath - -resize $newWidthx$newHeight\! $destinationImageFilePath");
echo '<b>New Width:</b>'.$newWidth;
echo "<br>";
echo '<b>New Height:</b>'.$newHeight;
pfarthing at hotmail dot com
11-Jan-2008 07:35
Correction: to find $y2 it should be...
// set y side to a proportional size
$y2 = $m * $x_max; // not $x1
Thanks Norbert =)
info at personalmis dot com
07-Jan-2008 08:42
Seems the various ways people are trying to proportionaly scale an image, up or down, could be more straight forward if one remembers ones algebra.
The formula is, y = mx, where m is the slope of the line. This is the ratio of y:x or m = y/x.
So if...
// max values for x and y
$y_max = 600;
$x_max = 800;
// image size
$y1 = 2000;
$x1 = 3000;
// use width for scaling
if ($x1 > $x_max)
{
// find slope
$m = $y1/$x1;
// set x side to max
$x2 = $x_max;
// set y side to a proportional size
$y2 = $m * $x1;
}
The new image proportionally scaled will be x2 = 800, y2 = 533 (rounded).
To do it from the y side, simply reverse the x's and y's.
redcore at gmail dot com
10-Aug-2007 05:50
It's always good to check out an image's dimensions while attempting to upload to your server or database...especially if it's going to be displayed on a page that doesn't accomodate images beyond a particular size.
<?php
//renumber
$my_image = array_values(getimagesize('test.jpg'));
//use list on new array
list($width, $height, $type, $attr) = $my_image;
//view new array
print_r($my_image);
//spit out content
echo 'Attribute: '.$attr.'<br />';
echo 'Width: '.$width.'<br />';
?>
phpnetUNDERSCOREspam at erif dot org
19-Jun-2007 03:26
an alternative to the three options below for finding the width and height of data you know to be an image:
$image = imagecreatefromstring($mydata);
$width = imagesx($image);
$height = imagesy($image);
boshka at gmail dot com
01-Feb-2007 09:40
I was trying to workaround with the problem of getting the mime type of the image from the raw data (the images data is stored in a database and the mime type is not known in advance). Since getimagesize requires a file name, there are some ways to deal with it:
1. call getimagesize with a URL which points to the image - this is too slow.
2. use PHP file i/o wrapper class.
3. use temporary files. The code for #3 could be as follows:
function getimagesize_raw($data){
$cwd = getcwd(); #get current working directory
$tempfile = tempnam("$cwd/tmp", "temp_image_");#create tempfile and return the path/name (make sure you have created tmp directory under $cwd
$temphandle = fopen($tempfile, "w");#open for writing
fwrite($temphandle, $data); #write image to tempfile
fclose($temphandle);
$imagesize = getimagesize($tempfile); #get image params from the tempfile
unlink($tempfile); // this removes the tempfile
return $imagesize;
}
jens at kulmegies dot de
31-Oct-2006 10:30
In addition to thomporter's quick-reference of the output array, here's what PHP 4.4.0 does:
There is no chance of getting the mime-type by accessing Array[6]...
egingell at sisna dot com
06-May-2006 06:14
<?
// These constants are used by image_info(), below.
define ('IMAGE_WIDTH', 'width');
define ('IMAGE_HEIGHT', 'height');
define ('IMAGE_TYPE', 'type');
define ('IMAGE_ATTR', 'attr');
define ('IMAGE_BITS', 'bits');
define ('IMAGE_CHANNELS', 'channels');
define ('IMAGE_MIME', 'mime');
/**
* mixed image_info( file $file [, string $out] )
*
* Returns information about $file.
*
* If the second argument is supplied, a string representing that information will be returned.
*
* Valid values for the second argument are IMAGE_WIDTH, 'width', IMAGE_HEIGHT, 'height', IMAGE_TYPE, 'type',
* IMAGE_ATTR, 'attr', IMAGE_BITS, 'bits', IMAGE_CHANNELS, 'channels', IMAGE_MIME, and 'mime'.
*
* If only the first argument is supplied an array containing all the information is returned,
* which will look like the following:
*
* [width] => int (width),
* [height] => int (height),
* [type] => string (type),
* [attr] => string (attributes formatted for IMG tags),
* [bits] => int (bits),
* [channels] => int (channels),
* [mime] => string (mime-type)
*
* Returns false if $file is not a file, no arguments are supplied, $file is not an image, or otherwise fails.
*
**/
function image_info($file = null, $out = null) {
// If $file is not supplied or is not a file, warn the user and return false.
if (is_null($file) || !is_file($file)) {
echo '<p><b>Warning:</b> image_info() => first argument must be a file.</p>';
return false;
}
// Defines the keys we want instead of 0, 1, 2, 3, 'bits', 'channels', and 'mime'.
$redefine_keys = array(
'width',
'height',
'type',
'attr',
'bits',
'channels',
'mime',
);
// If $out is supplied, but is not a valid key, nullify it.
if (!is_null($out) && !in_array($out, $redefine_keys)) $out = null;
// Get the image info using getimagesize().
// If $temp fails to populate, warn the user and return false.
if (!$temp = getimagesize($file)) {
echo '<p><b>Warning:</b> image_info() => first argument must be an image.</p>';
return false;
}
// Get the values returned by getimagesize()
$temp = array_values($temp);
// Make an array using values from $redefine_keys as keys and values from $temp as values.
foreach ($temp AS $k => $v) {
$data[$redefine_keys[$k]] = $v;
}
// Make 'type' usefull.
$data['type'] = $types[$data['type']];
?>
Russell Chappell
31-Mar-2006 11:01
For those of you who are confused about what the mime type IE displays image/pjpeg and other browsers image/jpeg and are building in checks for all of your scripts to tell the difference i would suggest using the getimagesize() mime results which will always be image/jpeg regardless what browser you use.
Where it says mime always is image/jpeg
John
06-Feb-2006 03:57
I was coming here to see if there was a simple way to get the height, width, and mime type of an image I have uploaded and while I thought the following code would work because it is printed above
<?php
list($width, $height, $type, $attr) = getimagesize("img/flag.jpg");
?>
it didnt when I tried to echo out $type; so heres my fix, there may be a better way but it works for me!
and then you can just echo out one of the variables about to get whichever you would desire.
gormozus at yahoo dot com
16-Nov-2005 02:56
getimagesize() seems to cache the results, so if you resize an image (using the methods described earlier) and you want to re-read its width and height, use imagesx() and imagesy() to get the actual information.
webmaster at WWW.ELLESSEWEB.NET
26-Oct-2005 08:10
This is a useful function to display a thumbnail of a whatever image.
This piece of code has been lightly modified from an example found on <b>NYPHP.ORG</B>.
This function can build a thumbnail of any size you want and display it on your browser!
Hope it can be useful for you guys!
<?php
function makeThumbnail($o_file, $t_ht = 100) {
$image_info = getImageSize($o_file) ; // see EXIF for faster way
switch ($image_info['mime']) {
case 'image/gif':
if (imagetypes() & IMG_GIF) { // not the same as IMAGETYPE
$o_im = imageCreateFromGIF($o_file) ;
} else {
$ermsg = 'GIF images are not supported<br />';
}
break;
case 'image/jpeg':
if (imagetypes() & IMG_JPG) {
$o_im = imageCreateFromJPEG($o_file) ;
} else {
$ermsg = 'JPEG images are not supported<br />';
}
break;
case 'image/png':
if (imagetypes() & IMG_PNG) {
$o_im = imageCreateFromPNG($o_file) ;
} else {
$ermsg = 'PNG images are not supported<br />';
}
break;
case 'image/wbmp':
if (imagetypes() & IMG_WBMP) {
$o_im = imageCreateFromWBMP($o_file) ;
} else {
$ermsg = 'WBMP images are not supported<br />';
}
break;
default:
$ermsg = $image_info['mime'].' images are not supported<br />';
break;
}
if (!isset($ermsg)) {
$o_wd = imagesx($o_im) ;
$o_ht = imagesy($o_im) ;
// thumbnail width = target * original width / original height
$t_wd = round($o_wd * $t_ht / $o_ht) ;
(where $file is something like "/rootdir/graphics/photo.jpg")
paul at goldenbakery dot nl
05-Aug-2005 05:02
Note that the canvas of a Flash movie can not be empty for getimagesize() to read the dimensions of an SWF. Not sure if this is a bug, a feature or just a limitation of the SWF format.
Flash version does not seem to matter. Also tested with Flash 8 beta.
Sean
31-May-2005 01:23
I needed a quick way to make a group of images uniformly sized, but only on one page. So creating a new set of thumbnails was overdoing the whole thing. I made up this script that seems to do the trick.
<?php
$image = "absolute/path/to/image/image.jpg";
$size = getimagesize("$image");
$height = $size[1];
$width = $size[0];
if ($height > 150)
{
$height = 150;
$percent = ($size[1] / $height);
$width = ($size[0] / $percent);
}
else if ($width > 150)
{
$width = 150;
$percent = ($size[0] / $width);
$height = ($size[1] / $percent);
}
echo "<img src\"image/path/image.jpg\" height=\"$height\" width=\"$width\" />";
?>
irregular at inbox dot ru
30-Apr-2005 07:24
I've wrote this piece of useful code.
May be it will be useful for you.
But i got a problem - if source image is in the area with need of authorization then the functions that read some files from that place (i.e. getimagesize, imagejpeg) does not work!
How to solve it?
<?php
//i't a stand-alone file named resize.php
//the feature is caching
// /image/thumbcache folder is used with file name forming by md5($img.$calc_width.$calc_height);
//it gets such parameters:
//img - image address (URL)
//w - optional width
//h - optional height
//if you set either w or h, then the image is resized proportionaly, according to the source
//if you set neither w nor h then the script just output file
//if you set both w or h then the image will be resized exactly how you want
?>
ajreading at classixshop dot com
21-Apr-2005 04:30
A simple piece of code i wrote to proportionally resize an image to a max height and width then display it
<?php
// Max height and width
$max_width = 100;
$max_height = 100;
// Create the new image!
$src = ImageCreateFromJpeg($upfile);
$dst = ImageCreateTrueColor($tn_width, $tn_height);
ImageCopyResized($dst, $src, 0, 0, 0, 0, $tn_width, $tn_height, $width, $height);
ImageJpeg($dst);
// Destroy the images
ImageDestroy($src);
ImageDestroy($dst);
?>
mail at soylentgreens dot com
31-Mar-2005 10:37
How about this for cropping images...
// TODO: write code to save new image
// or, just display it like this:
header("Content-type: image/jpeg");
imagejpeg($cropimg);
// destroy the images
imagedestroy($cropimg);
imagedestroy($origimg);
?>
Coodiss at w3bbix dot net
16-Mar-2005 01:51
Heres a easy way to scale images to the <td> that they are in
*this is broken up so anyone can understand it :)
?>
php dot net at dannysauer dot com
13-Feb-2005 12:23
Note that, if you're going to be a good programmer and use named constatnts (IMAGETYPE_JPEG) rather than their values (2), you want to use the IMAGETYPE variants - IMAGETYPE_JPEG, IMAGETYPE GIF, IMAGETYPE_PNG, etc. For some reason, somebody made a horrible decision, and IMG_PNG is actually 4 in my version of PHP, while IMAGETYPE_PNG is 3. It took me a while to figure out why comparing the type against IMG_PNG was failing...
sixzero4 at hotmail dot com
30-Nov-2004 12:33
This is just to add to the comment by robertks at hotmail dot com on
05-Mar-2003 12:12 regarding trying to derive the dimensions of a video file. The package referenced (http://www.getid3.org/) had been updated, and below is a script I use to get the size. You can get many other attributes of media files as well.
<?php
// include getID3() library (can be in a different directory if full path is specified)
include_once('getid3.php');
// Initialize getID3 engine
$getID3 = new getID3;
// File to get info from
$file_location = './your/path/to/file.mov';
// Get information from the file
$fileinfo = $getID3->analyze($file_location);
getid3_lib::CopyTagsToComments($fileinfo);
// Output results
if (!empty($fileinfo['video']['resolution_x'])) { echo '<p> video width: '.$fileinfo['video']['resolution_x'].'</p>'; }
if (!empty($fileinfo['video']['resolution_y'])) { echo '<p> video height: '.$fileinfo['video']['resolution_y'].'</p>'; }
?>
Hope that helps others looking for a function similar to getimagesize() for a video or media file.
Joshua
17-Aug-2004 03:26
If your image name has spaces in it you will need to use rawurlencode() and NOT urlencode() as this function (at least in 4.3.4) does not accept spaces as + signs.
cstdenis at hotmail dot com
12-Aug-2004 02:42
This will not work for swf files unless zlib is compiled into php statically (not as a shared module). Bug #29611
As of PHP 5.0.0 it will just return false, but that should change to a notice by the next release.
ryan at vitalmodels dot com
05-Jun-2004 04:06
--- Editor's Note:
It's easier to call on urlencode() or rawurlencode() to "fix" urls containing spaces and other characters that normally not well-liked.
---
You may have noticed that images with spaces WONT work with getimagesize - some of us have massive amounts of pictures, or don't feel like rewriting file names on users uploaded pictures- so here is a super fast fix that will replace the spaces once the image is called and will work with getimagesize flawlessly-
Now you just call $image_new using getimagesize and you wont' have anymore problems.
On my site I take uploaded pictures from users - then resize them if they are over a certain width, here is the script i use if anyone would like to do this-
$image_new = "/pictures/$pic[picture]"; //url of picture
$image_new = str_replace(' ','%20',$image_new); //take url and replace spaces
$max_width= "480"; //maximum width allowed for pictures
$resize_width= "480"; //same as max width
$size = getimagesize("$image_new"); //get the actual size of the picture
$width= $size[0]; // get width of picture
$height= $size[1]; // get height of picture
if ($width>$max_width){
$new_width=$resize_width; // Resize Image If over max width
}else {
$new_width=$width; // Keep original size from array because smaller than max
}
echo "<IMG src=\"$image_new\" border=1 width=$new_width>" //print image with new width
Hope this helps anyone who wants some simple uses for getimagesize- check out my website to see it in action- vitalmodels.com
diablx at hotmail dot com
26-May-2004 05:36
I'm sorry for they other scripts, but I made one mistake about the image resizing... here is a working script !
<?
// Some configuration variables !
$maxWidth = 90;
$maxHeight = 90;
$maxCols = 8;
$webDir = "https://localhost/images/";
$localDir = $_SERVER['DOCUMENT_ROOT']."/images/";
if($i == $maxCols) {
echo "</tr><tr>";
$i = 0;
}
echo "<td align='center' valign='middle' width='$maxWidth' height='$maxHeight'><img src='".$webDir.$images."' width='$newWidth' height='$newHeight'></td>";
$i++;
}
}
?>
</tr>
</table>
</center>
MagicalTux at FF.st
31-Mar-2004 07:35
simm posted something interesting about imagick, but usually calling an external binary is not the best way.
You can use the Imagick PHP module . With it, you do not even need to get the image size to generate thubnails...
Here's the code I used :
<?php
$imh=imagick_readimage($image);
imagick_scale($imh,GALLERY_THUMBNAILWIDTH,GALLERY_THUMBNAILHEIGHT);
imagick_writeimage($imh,$image_thumb);
?>
(I noticed that some hosting companies are now providing the imagick module by default. Using it allows you to accept any type of image from your visitors. Maybe it will be documented on the official PHP website one day or another? )
MarioPro
11-Mar-2004 10:13
The Problem:
I've just noticed that after upgrading to the PHP 4.3.4 version, the old GetImageSize() should get your attention on pages coded before this new version.
The solutions:
So, if you used GetImageSize(), you should now be using getimagesize() - attention to all lower caracters.
Also, you shou certify that the image realy exists, otherwhise you'll get the following error: getimagesize(): Read error!
This means that there is no image to "fill" the string and thus you're calling, for example: "images/news/" instead of calling "images/news/03102004a.jpg"
One should now verify if there is an image to be called (example):
if($photo1!=""){
$size1=getimagesize("images/news/".$photo_news_1"]);
$width1=$size1[0];
$height1=$size[1];
}
Here, if $photo_news_1 is set and exists it will be displayed, otherwhise it will be skiped and no ERROR message will be displayed. In the PHP 4.3.3 and earlier versions, this was not necessary but it is now! ;)
yohami dot com - zerodj at hotmail dot com
14-Jan-2004 11:11
A cool resize / cropping script for creating thumbnails using mogrify
IMAGETEST.PHP
<?php
include 'mogrify.php';
// variables from flash (my website uses flash and php)
$picture="sample.jpg";
$fixedwidth=300;
$fixedheight=240;
//
yeah!
php (at) thejpster org uk
02-Dec-2003 10:39
If you want to resize an image proportionally to fit within a given area, like I did, the following code might help you out.
If either hscale or wscale are greater than 1 then that dimension is too big. If you then scale your image by the larger of the two values (hscale, wscale) then you guarantee that both dimensions will now fit in your specified area :)
return "<img width='$newwidth' height='$newheight' src='$image'><br>$image: $newwidth x $newheight : $width x $height";
}
djwishbone at hotmail dot com
19-Nov-2003 10:31
Using remote files with getimagesize($URL) never worked for me. Except when I would grab files from the same server. However, I developed some code with the help from the people here that does work. If you are having problems give this function a shot:
$im = ImageCreateFromString($contents);
if (!$im) { return false; }
$gis[0] = ImageSX($im);
$gis[1] = ImageSY($im);
// array member 3 is used below to keep with current getimagesize standards
$gis[3] = "width={$gis[0]} height={$gis[1]}";
ImageDestroy($im);
return $gis;
}
goodluck
janoma_cl
10-Oct-2003 06:19
If you want to show thumbnails keeping the original proportions, with defined maximum width and height, you can use this function. This is useful when showing tables of user-uploaded images, that not necessarily are same-sized. However, for big images (like wallpapers), a better option is to create separated thumbnails with a image-editing software.
If the image is smaller or equal than the defined maximums, then it's showed without resizing. If not, creates a link to a pop-up that shows the full-size image.
<?php
function show_thumbnail($file)
{
$max = 200 // Max. thumbnail width and height
$defaultImgWidth would be the target width of the image -- note that the code above resizes the image without distorting its original proportions, and only if it is wider than $defaultImgWidth.
the ImageMagick syntax used above ("mogrify ..") overwrites the original file ($uploadName) with the resized image.
ten tod xmg ta rotanimrev (reverse it)
02-Sep-2003 01:30
An additional note to "tightcode_nosp@m_hotmail":
Though keep in mind that this consumes lots of CPU. So if you're doing something like creating a page of thumbnails this is considerably slower.
So what you can do is use getimagesize() and check if
- the width and height are empty strings ("")
- and those two values aren't too high
Both indicate that getimagesize() didn't work properly. The latter may happen if getimagesize() thought that it recognized the format and therefore the size properly. I mean if you're looking at pictures that you know are max. 1024x768 and getimagesize() returns a width of e.g. 20234 then it's obvious that something went wrong. In that case use the code mentioned above. Of course if getimagesize() returned small values that are wrong you still get the wrong size. So check your pictures and priorities first.
Note: fix syntax stuff if there's an error as I compiled this example from a few places.
If you don't care about the huge load on your CPU or you have to rely on the proper size use the snippet noted at the beginning only.
justin at webtekconcepts dot com
16-Aug-2003 04:27
For those that like to go the dynamic thumbnail route, I've found that you can get warnings with getimagesize() after your loop through more than 3 to 4 images. In my case I needed 12 images on each page.
Use usleep() in your loop just before you run getimagesize() otherwise you'll end up with warnings, big images and a broken page. Using usleep() lets the server recoup for X milliseconds so it will accept connections again for the image size.
I've found that usleep(1500) is the best for my situation. This barely slows the page down and allows for getimagesize() to work 100% of the time for me.
webmaster AT theparadox DOT org
31-May-2003 08:16
I figured others have wanted to scale an image to a particular height or width while preserving the height/width ratio. So here are the functions I wrote to accomplish this. Hopefully they'll save somebody else the five minutes it took to write these.
You give the filename and the dimension you want to use, and these functions return the opposite dimension:
function scale_to_width ($filename, $targetwidth) {
$size = getimagesize($filename);
$targetheight = $targetwidth * ($size[1] / $size[0]);
return $targetheight;
}
robertks at hotmail dot com
06-Mar-2003 01:12
For those of you trying to derive the dimensions of a video file (e.g. Video for Windows AVI, Quicktime MOV, MPEG MPG, Windows Media Video WMV or ASF, etc.), you will find the getid3 library to be indispensible. Found at http://getid3.sourceforge.net, here's an example of its use in a script:
include_once('getid3.php'); // or wherever you actually put the getid3 scripts
$file_location = './myvideo.avi';
$file_info = GetAllFileInfo($file_location) // calls getid3 function
$file_width = $file_info['video']['resolution_x'];
$file_height = $file_info['video']['resolution_y'];
You can then use your OBJECT and EMBED tags in HTML to put the video into a web page, and make the PHP template independent of the size parameters of the particular video it happens to be loading. (Just remember to add pixels to the video height to accomodate the controller of the embedded player: typically, 16 pixels for Quicktime, 46 pixels for Windows Media Player 6, and 64 pixels for Windows Media Player 7.
mogster at boomdesign dot no
10-Mar-2002 02:58
Really useful info from webmasterb@feartheclown.com and you others :-)
Saved my butt...
Here's a build on that, with proportional resizing of the image-upload ($newpic) to a fixed value ($maxwidth):
$maxwidth = "350";
$imagehw = GetImageSize($newpic);
$imagewidth = $imagehw[0];
$imageheight = $imagehw[1];
$imgorig = $imagewidth;
if ($imagewidth > $maxwidth {
$imageprop=($maxwidth*100)/$imagewidth;
$imagevsize= ($imageheight*$imageprop)/100 ;
$imagewidth=$maxwidth;
$imageheight=ceil($imagevsize);
}
Of course this does not resize the image itself, but returns values one may use in html-code to restrain users from killing your design...