Image resize / autofit

Hi, thanks to the help of Experts, I have managed to make a util to allow users on my site to browse to an image on their disks and upload it to my server and automatically display it on their pages,
Now, I want to go one step further, to automatically resize / autofit to the best dimensions in the space that I provide.

I have seen comments about imagemagic, but couldn't find examp0les simple enough for me to understand. Could someone here pleaae try to give me an example of how to do this.
It doesn't HAVE to be with using imagemagic, a simple algorith reading the width and height of image at upload time adn then proportionally resizing the image to fit within a pre-set (x,y) will do also.

Thanks
LVL 17
psimationAsked:
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icewolf_liConnect With a Mentor Commented:
At first you should install GD library for php, then u can use gd functions as follow:

/*
rend a new $dstFile from $srcFile,with the max size limit $maxsize.
*/
function RendSmall($srcFile,$dstFile,$maxsize) {
     
     $data = GetImageSize($srcFile,&$info);
     switch ($data[2]) {
          case 1:
          $im = @ImageCreateFromGIF($srcFile);
          break;
          case 2:
          $im = @imagecreatefromjpeg($srcFile);
          break;
          case 3:
          $im = @ImageCreateFromPNG($srcFile);
          break;
          default:
               return -1;
     }
     if(!$im)
          return -1;

     $dstW = $data[0];
     $dstH = $data[1];
     $dstX = 0;
     $dstY = 0;
     if($data[0]>=$data[1]){
          if($data[0] > $maxsize){
               $dstW = $maxsize;
               $dstH = $maxsize * $data[1] / $data[0];
               $dstY = ($maxsize-$dstH)/2;
          }
          else{
               $maxsize = $data[0];
               $dstY = ($data[0]-$dstH)/2;
          }
     }
     else{
          if($data[1] > $maxsize){
               $dstW = $maxsize * $data[0] / $data[1];
               $dstH = $maxsize;
               $dstX = ($maxsize-$dstW)/2;

          }
          else{
               $maxsize = $data[1];
               $dstX = ($data[1]-$dstH)/2;
          }
     }
     $srcW=ImageSX($im);
     $srcH=ImageSY($im);
     $ni=ImageCreate($maxsize,$maxsize);
     
     if(!$ni || !(ImageCopyResized($ni,$im,$dstX,$dstY,0,0,$dstW,$dstH,$srcW,$srcH)) )
          return -1;
     if(!ImageJpeg($ni,$dstFile))
          return -1;
     
     return 1;
}
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psimationAuthor Commented:
Sorry for the delay.
Can you help me to get GD installed first? I tried, but cannot get it right.
HAve RH7.0 with PHP that seems to have been installed with the --without-gd switch, I don't want to re-istall the entire PHP, so if you have  a solution to load it at runtime, it would be much better solution.

Thanks
0
 
psimationAuthor Commented:
OK, this question didn't help me as I couldn't get GD installed, but I guess, for others out there, it might help, so there are merrit in having this question in the archives...
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