Resizing a single file

[jazztie]

Hi,
I have a site where pictures are shown for visitors. The admin of the site wants to show one of the pictures on the front page - which he can choose from the list of the pictures available.

I want to resize that picture (say, it has variable $MainPagePic) and show it on the mainpage. So - no saving the file to any other file... just resize and post it. I also want to check the max width and height (which ever comes first)

example:
max width: 300 // max height: 300
photo1.jpg (w: 600 h: 400) >> resize >> <img src='photo1.jpg'> (w: 300 h: 200).
photo2.jpg (w: 400 h: 600) >> resize >> <img src='photo2.jpg'> (w: 200 h: 300).

How can this be done easily?

Any help is appreciated.
Jazz

[phreaq]

$file = $imgFile;

$nameArray = split(".jpg", $file);
$name = $nameArray[0];

if(!file_exists($name."_thumbnail.jpg"))
{

$img1 = getimagesize($file);
    if ($img1[2] == 2) { 
	


$img = ImageCreateFromJpeg($file); 
$img_size = getimagesize($file);
$img_w = $img_size[0];
$img_h = $img_size[1];
$destimg_w = 300;
$destimg_h = 300;


$mlt_w = $img_w / $destimg_w ;
$mlt_h = $img_h /$destimg_h ;

if($mlt_w < $mlt_h)
  {
  
  $re_img_h = $img_h / $mlt_h;
  $re_img_w = $img_w / $mlt_h;
  
  }
  else
  {
   $re_img_h = $img_h / $mlt_w;
  $re_img_w = $img_w / $mlt_w;
  
  }

$img_resized = imagecreatetruecolor( $re_img_w,  $re_img_h);
imagecopyresampled($img_resized, $img, 0, 0, 0, 0, $re_img_w, $re_img_h, $img_w,$img_h);
ImageJPEG($img_resized, $name."_thumbnail.jpg", "80");
	}
}



$imgFile = $name."_thumbnail.jpg";

This will create a copy of your current file called oldfile_thumbnail.jpg with 300px width and hight keeping constrains.

hope this will do the job

grtz Martijn Schot

[jazztie]

The file won't be saved anywhere, will it? (I don't want it to)
I just want to resize it and print it on screen.

PS: thanx for the code

[7stud]

Have your admin put this on his page with the name of your php file and the path to your image:

<img src="atest3.php?img=../images/105_0532.jpg" />

Then try this:

$fname = $_GET['img'];

$copy = imagecreatefromjpeg($fname);
$oldWidth = imagesx($copy);
$oldHeight = imagesy($copy);

$max = 300;

if($oldWidth > $oldHeight)
{
    $newWidth = 300;  //If oldWidth was 600, then newWidth  
             //is 300/600 smaller and that fraction needs to be 
             //multiplied by the oldHeight to get the new height

    $newHeight = (300/$oldWidth) * $oldHeight;  
}
else
{
    $newHeight = 300;
    $newWidth = (300/$oldHeight) * $oldWidth;
}

$newImg = imagecreatetruecolor($newWidth, $newHeight);
imagecopyresampled($newImg, $copy, 0,0,0,0, $newWidth, $newHeight, $oldWidth, $oldHeight); 

header('Content-Type: image/jpeg');
imagejpeg($newImg);

imagedestroy($copy); 
imagedestroy($newImg); 

Edit:

Added two lines at the end.

[7stud]

By the way, you need to to check to see if your server has the gd library enabled and that it is version 2.0+. Do this:

phpinfo();

and look under the 'gd' heading.