Plz help ! Creating temporary jpg file !

Roel018

Dear folks,

I'm working on a page which needs to handle base64-encoded jpg files. I need to decode them and be able to use it further on on the for viewing. I do not want a jpg-onky page with the result, but need to place it in a table, etc. Problem is, with my current script (see below), the encoded file gets copied, renamed and is usable for viewing, but next this image just resides on the server, while it should be deleted after the image is loaded onto the client's screen. I tried to delete the copied file after the lines of code to display the image, but then the browser says no image is found....

How can I solve this problem ? I'm no genius in PHP (i'm an ASP programmer) so I've tried everything my PHP knowlegde ables me to...

Hope to hear from you !

Code:

<?php
//READ FILE NAME TO VIEW FROM POST VARS:
//--------------------------------------
import_request_variables("P", "mypost_");


// DEFINE VARS:
//-------------
$imagename = $mypost_filename;
$imagetitle = $mypost_imagetitle;
$secured_imagename = $imagename.".php";
$path = "yourmammasuploads/";
$targetpath = $path.$secured_imagename;
$tempfile = $targetpath.".jpg";


//REMOVE SECURITY LINE IN FILE AND DECODE FILE CONTENTS:
//------------------------------------------------------
$data = file($targetpath);
array_shift($data);
$data = implode('', $data);
$file = base64_decode($data);


// WRITE NEW NON-SECURED TEMPORARY FILE FOR VIEWING:
//--------------------------------------------------
$f = fopen($tempfile, 'w');
fwrite($f, $file);
fclose($f);


//ALL DONE
//--------
echo "All done. Temp image ready for viewing:<br><br>";
echo "<img src='" . $tempfile . "'><BR>";
echo $imagetitle;
EXIT;

?>

Regards,
Roel

Weedpacket

Have the <img>'s src URL point to a script that generates the jpeg and outputs it directly. Only fiddly bit is that the URL would need a querystring that contains a field to identify which image to generate.

(If IE supported data: URLs, that would have been another possibility. But it doesn't, so it's not.)

Roel018

Weedpacket wrote:
Have the <img>'s src URL point to a script that generates the jpeg and outputs it directly. Only fiddly bit is that the URL would need a querystring that contains a field to identify which image to generate.

(If IE supported data: URLs, that would have been another possibility. But it doesn't, so it's not.)

Ok i've done the following: created a session for the image viewing procedure, changed the script so it now calls a php file to dump the image (see below) and call the stored session var containing the image filename from within that script. This works, however, now I have the result I want - but with an image which is name 'callimage.php', which isn't saveble by the client because when this image is downloaded the client has a callimage.php file, and when renamed to .jpg it's not readable... So somehow this isn't perfect, cause I really need the client to be able to download it's images - that's what it is all about....

What to do ?????

Readimage.php:

<?php
//READ FILE NAME TO VIEW FROM POST VARS:
//--------------------------------------
import_request_variables("P", "mypost_");


// DEFINE VARS:
//-------------
$imagename = $mypost_filename;
$imagetitle = $mypost_imagetitle;
$secured_imagename = $imagename.".php";
$path = "yourmammasuploads/";
$targetpath = $path.$secured_imagename;
$tempfile = $targetpath.".jpg";


//START SESSION:
//---------------
//This call either creates a new session or re-establishes an existing one.
session_start();


//SET SESSION VARS:
//-----------------
$_SESSION["targetJPG"] = $targetpath;


//SET SESSION ID:
//---------------
$sessionId = session_id();



//ALL DONE
//--------
echo "All done. Temp image ready for viewing:<br><br>";
echo "<img src='" . "callimage.php?PHPSESSID=" . session_id() . "'><BR>";
echo $imagetitle;
EXIT;

?>

Callimage.php:

<?php
//READ SESSION & READ VARS:
//-------------------------
//This call either creates a new session or re-establishes an existing one.
session_start();
$jpgSource = $_SESSION["targetJPG"];


//REMOVE SECURITY LINE IN FILE AND DECODE FILE CONTENTS:
//------------------------------------------------------
$data = file($jpgSource);
array_shift($data);
$data = implode('', $data);
$file = base64_decode($data);


header ("Content-type: image/jpg");
echo $file;

?>

Weedpacket

Well, you shouldn't need to attach the session ID, because the browser will be doing that already anyway.

You can send a header that provides a better filename than the default one the browser constructs from the URL. A slight tweak to one of the examples given in the manual for the [man]header[/man] function should make things happy:

header('Content-Disposition: inline; filename="ABetterName.jpg"');

(Oh, and just being picky here, but the MIME type for JPEG images is "image/jpeg".)

Roel018

Weedpacket wrote:
Well, you shouldn't need to attach the session ID, because the browser will be doing that already anyway.

You can send a header that provides a better filename than the default one the browser constructs from the URL. A slight tweak to one of the examples given in the manual for the [man]header[/man] function should make things happy:
header('Content-Disposition: inline; filename="ABetterName.jpg"');
(Oh, and just being picky here, but the MIME type for JPEG images is "image/jpeg".)

Ok, it works ! Thnx for that ! But there's still one little question I have.
As you see, I'm using a session each time I call an image because I cannot work with global vars on my server... So in order to have the callimage.php script to know what image to read when I'm calling it from readimage.php (see my code snippets above), I need to create a session.. Isn't there any work around to solve this ??? Because to start and end a session each time a image has to be displayed, isn't very cool, or is it ?

Thnx!

Regards,
Roel