Image Resize using MYSQL Datatbase

blkrt10

Hi, i am trying to display an image on an html page usign the below fetch script to pull an image from a database. This script will not work because my $img variable is a binary resource, not a path like getimagesize wants. What changes can i make to accomodate this case?

Thanks in advance
<?php
if(isset($GET['car_id']) && isset($GET['image_num']))
{
$car_id = $GET['car_id'];
$img_num= 'img';
$img_num .= $GET['image_num'];
//Get Image
require_once ('dbconnect.php');
$sql = "select $img_num from auto where id=$car_id";
$imgresult = mysql_query("$sql");

header("Content-type: image/jpeg;");
$img = mysql_result($imgresult, 0, $img_num);

$percent = 0.5;
list($width, $height) = getimagesize($img);
$new_width= $width * $percent;
$new_height = $height * $percent;

//Resample
$image_p = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefromjpeg($img);
imagecopyresampled($image_p, $image, 0,0,0,0, $new_width, $new_height, $width, $height);
imagepeg($image_p, null, 100);

}
?>

Installer

You could write it to a temporary file:

$img = mysql_result($imgresult, 0, $img_num); 
$fp = fopen('tmp.jpg', 'wb');
fwrite($fp, $img);
fclose($fp);
$image = imagecreatefromjpeg('tmp.jpg');
unlink('tmp.jpg'); 
$width = imagesx($image);
$height = imagesy($image);
// etc.

blkrt10

Thank you, that worked, however I wonder about the performance implications that would come from continously doing that. The site would host approx 10-20 users max at a time, and that would serve up approx 100 images per user....

Installer

I think you'll find the time taken by the file writing is small compared to the time used by the image functions, but it's a legitimate concern. The solution to this and other problems caused by storing images in your database? Don't store images in your database.

MikeSnead

http://www.php.net/manual/en/function.imagecreatefromstring.php

The above function will let you do all the fun GD library functions on an image pulled from a database.

Also, storing images in a database is a perfectly viable solution. The problem usually comes in when people do things like 'SELECT * FROM images' when they only need the image ID and width (or something). Build your queries appropriately and you'll be good to go.

blkrt10

I get confused about when php wants a binary image, or the path... so if i do the imagecreatefromstring, then i do NOT need to do the temporary file write?

Thanks for all of the suggestions!

MikeSnead

Originally posted by blkrt10
I get confused about when php wants a binary image, or the path... so if i do the imagecreatefromstring, then i do NOT need to do the temporary file write?

Thanks for all of the suggestions!

Correct 🙂