Why is this code making my page load slowly?

Jsn7821

I have a script where I can upload images, and then my script resizes them (and does a number of other things with it, but this part is making it go slow).

if ($imagelink != NULL) { 
$imagelinksize = getimagesize(ereg_replace(" ", "%20" , "$imagelink"));
$lwidth = $imagelinksize[0];
$lheight = $imagelinksize[1];
echo "<a href=\"$imagelink\"><img src=\"$imagelink\" ";
echo image_size($lwidth,$lheight);
echo "></a>"; 
}

$imagelink would be http://www.guster.com/road/ryansumo.jpg

someone else posted it on the script and it made it slow. The funny thing is the entire page didnt load for about 15 seconds, then it showed up. If that host was slow wouldn't the page load and the image slowly load? That's what has me confused and why I am thinking it's in my php.

wilku

It's only my opinion, but I think that the problem lies in getimagesize. You try to get the size of an external image. At that point the script pauses, waiting for result. As it finds the result, it goes without any further problems.
Solution? Maybe not very elegant, but do not check the size of external files.

Jsn7821

Originally posted by wilku
It's only my opinion, but I think that the problem lies in getimagesize. You try to get the size of an external image. At that point the script pauses, waiting for result. As it finds the result, it goes without any further problems.
Solution? Maybe not very elegant, but do not check the size of external files.

But wouldn't the page display everything up untill that point? I call that function after I have echoed out a number of tables and other text.

wilku

To send all the buffered data, use [man]flush()[/man] before the point, where you get the image size. It should send to browser all the contents up to the point.

Jsn7821

Ah it worked. It pauses right before the picture loads, then once it gets the image information the rest of the page loads. Thanks for the help.

Is there any (simple) way that I could basically make it run the entire script while its loading the image, so that everything shows up and then when it finishes loading it shows the image? The more I type the more I realize how that isn't possible... or is it..!?

wilku

My point in the first reply was, that you don't wait for the picture to load by browser, but you wait for the getimagesize function to contact the external server (and possibly download the file for the need of the script). If you've got the images stored locally - use local paths on the server, then it shouldn't take so long. When the files are somewhere outside, forget about checking the size, just output <img src=""> and let the browser worry. It will display all the textual content and download image later.

Jsn7821

Oh that is a good idea. I will just make my script upload the images to the server when they are posted, that way I wont be using other peoples bandwidth also.

Thanks for the advice.

The only reason i wouldnt just use <img src=> is that im using the getimagesize along with a function I made to resize the images before they are posted.