Image resize help

mrbluesbox

Hi,
can anybody help me with resizing images. I have the following code that appears to work fine apart from when you start to use large images (some of the images i need to upload and resize are about 2500x1500 pixels and about 1mb in size).
When i try to resize one of these, the file outputed is simply a black square 🙁
Does PHP have a limitation on image size or is it my code?
any help would be much appreciated.

==============================================
function resize($IMAGE,$NEW_X,$NEW_Y,$OUTPUT_FILE)
{
$BACKUP_FILE = $OUTPUT_FILE . "_backup.jpg";
copy($IMAGE,$BACKUP_FILE);
$IMAGE_PROPERTIES = GetImageSize($BACKUP_FILE);
if (!$IMAGE_PROPERTIES[2] == 2)
{
return(0);
}
else
{
//Create our source image
$SRC_IMAGE = ImageCreateFromJPEG($BACKUP_FILE);

   //Keep the aspect ratio of the image
   $SRC_X = ImageSX($SRC_IMAGE);
   $SRC_Y = ImageSY($SRC_IMAGE);	   
   $NEW_X = (int)($NEW_X);
   $NEW_Y = (int)($NEW_Y);

   //Create our desination image size
   $DEST_IMAGE = imagecreatetruecolor($NEW_X, $NEW_Y);

   //Destroy the backup image
   unlink($BACKUP_FILE);

   //resize the image
   //$resize results = imagecopyresized($DEST_IMAGE, $SRC_IMAGE, 0, 0, 0, 0, $NEW_X, $NEW_Y, $SRC_X, $SRC_Y);
   imagecopyresampled($DEST_IMAGE, $SRC_IMAGE, 0, 0, 0, 0, $NEW_X, $NEW_Y, $SRC_X, $SRC_Y);	   	   
   echo "About to output resized image";
   if (ImageJPEG($DEST_IMAGE,$OUTPUT_FILE)) 
   {
   		return(1);
   }

   imagedestroy($SRC_IMAGE);
   imagedestroy($DEST_IMAGE);
   return(0);

}

Mordecai

Do you get any errors? I'd figure that would exhaust PHP's memory very quickly. You may try upping the amount of memory your script can use, check out memory_limit in php.ini.

And please erase your other topic. If you need to know how, click 'edit' in the bottom, and then check 'Delete?' at the top, and press 'Delete Now.'

mrbluesbox

   //Keep the aspect ratio of the image
   $SRC_X = ImageSX($SRC_IMAGE);
   $SRC_Y = ImageSY($SRC_IMAGE);	   
   $NEW_X = (int)($NEW_X);
   $NEW_Y = (int)($NEW_Y);

   //Create our desination image size
   $DEST_IMAGE = imagecreatetruecolor($NEW_X, $NEW_Y);

   //Destroy the backup image
   unlink($BACKUP_FILE);

   //resize the image
   //$resize results = imagecopyresized($DEST_IMAGE, $SRC_IMAGE, 0, 0, 0, 0, $NEW_X, $NEW_Y, $SRC_X, $SRC_Y);
   imagecopyresampled($DEST_IMAGE, $SRC_IMAGE, 0, 0, 0, 0, $NEW_X, $NEW_Y, $SRC_X, $SRC_Y);	   	   
   echo "About to output resized image";
   if (ImageJPEG($DEST_IMAGE,$OUTPUT_FILE)) 
   {
   		return(1);
   }

   imagedestroy($SRC_IMAGE);
   imagedestroy($DEST_IMAGE);
   return(0);

}

Weedpacket

Is the script timing out after 30 seconds (the default)? It's not a limitation on memory usage or uploaded file size (set either in php.ini or in the server's own configuration)? Have you tried images with big dimensions and small file sizes in an attempt to see what qualifies as "large"?