resizing an image with php...

dawson1323

I am looking for a way to scale down an image and save it as another name.

What I am trying to do is make a part of an administration site where you can select an image you have and make a thumbnail of it.

Anything will help, I don't even know where to start.

Thanks,

-D

michael

Admit it, you're making a pron site.

$src_img = imagecreatefromjpeg("/path/to/$my_src_file");
$dst_img = imagecreatetruecolor($dest_width,$dest_height);
imagecopyresampled($dst_img, $src_img, 0, 0, 0, 0, $dest_width, $dest_height, $src_width, $src_height);
imagejpeg($dst_img, "/path/to/storage/new_file.jpg", $quality);
imagedestroy($src_img);
imagedestroy($dst_img);

I also recommend using int imageinterlace ( resource image [, int interlace]). It makes the JPEG image progressive. I assume you're using JPEGs. You didn't specify.

You're welcome to contact me or post questions here.

Phantazm

micheal... your posted code works perfectly assuming the GD2 library is in use... but just in case, here's how I would probably modify the code slightly...

  $src_img = imagecreatefromjpeg("/path/to/$my_src_file"); 
  $dst_img = imagecreatetruecolor($dest_width,$dest_height); 
  if(function_exists("imagecopyresampled"))
  {
    imagecopyresampled($dst_img, $src_img, 0, 0, 0, 0, $dest_width, $dest_height, $src_width, $src_height); 
  }
  else
  {
    imagecopyresized($dst_img, $src_img, 0, 0, 0, 0, $dest_width, $dest_height, $src_width, $src_height); 
  }
  imagejpeg($dst_img, "/path/to/storage/new_file.jpg", $quality); 
  imagedestroy($src_img); 
  imagedestroy($dst_img);

And, as an added note, imagecopyresampled is FAR superior to imagecopyresized, so if possible... make SURE your host / server supports it

As usual.. just my 2 cents 🙂

michael

Althought I use that code, I did not write it. Credit is due to the guys at PHP.net.

Additionally,
if (PHP_VERSION >= 4.3) {
if (function_exists("imagetypes"))
{
$gdversion = 1;
if (function_exists("imagecopyresized")) {
$gdversion = 2;
}
}
}

dawson1323

OK, super dumb followup question........

What is the deal when I get the error:

Fatal error: Call to undefined function: imagecreatefromjpeg()

-D

Weedpacket

Originally posted by dawson1323
OK, super dumb followup question........

What is the deal when I get the error:

Fatal error: Call to undefined function: imagecreatefromjpeg()

Not a dumb question; none of the given examples will work if there's no gd_lib installed at all. On a Windows machine it's just a matter of uncommenting the appropriate line in php.ini, on a *nix machine it involves getting and installing gd_lib (and libjpeg if it's not already there) and recompiling PHP to use it. I've got to get going now, so I don't really have time to provide a link to the image functions section in the manual - but you'll find futher details there.

gmbpro

...and what if the relevant stuff is already uncommented (i mean extension=php_gd.dll and extension_dir = E:/PHP) and still can't use the gd library?

BKG: PHP v4.2.3, Win2000/srv

thx,
gmbpro

dawson1323

Ok, so I uncommented the correct things in php.ini, and then I checked my php directory and found that I had no .dll modules in there.....

How do I get these? are they downloadable from some where, I really only need php_gd.dll

thanks,

gmbpro

RE: And yet another question...

Well, PHP_gd.dll is part of the PHP v4.0.4 installation kit (at least).
You can find it into subdirectory \php\extensions.
To enable it just uncomment the relevant line in php.ini to enable the graphic engine (also, don't forget to setup extension_dir = <your-drive>:/PHP/extensions, while in php.ini).

Still, I couldn't make php v4.2.3 to work.

Ideas anyone?

Ciao, gmbpro.

dawson1323

OK! got the extesionsthing figured out, now I get this:

Fatal error: Call to undefined function: imagecreatetruecolor()

still missing something??? I am using the exact code (well plus somethings like setting what all of the variables are equal to) that Phantazm posted earlier.

-D

bbaassiri

try copying the dll in to the win or winnt folder that might work