Force a download link once image is resized

Question

I am working on a wordpress cms. I have a little no-fancy php script which basically resizes the uploaded image to assigned limits, and outputs the resized image back to the visitor's browser, so he can right-click-download. Given below is a relevant portion of the script, but if need I shall provide complete code.

ob_start();
imagejpeg($new, null, 100); 
echo '<img src="data:image/jpeg;base64,' . base64_encode(ob_get_clean()) . '">';
echo '<br><br>RIGHT CLICK AND SAVE IMAGE<br><br>';
imagedestroy($new);

Bottomline is I would like to force the download link for the resized image, once resize is done.

EFFORTS AND UPDATES:

First update: I am currently going through this article on forced-download-links as suggested on another relevant thread on SO. But I am stcuk when it says - "First things first… we need to define the path to our file in PHP (as a string).". Problem is, since I do not want any image file saved on my server and so the second parameter of the imagejpeg() function is set to NULL. So I cannot define a path to my file. Or can I ? How do I do this. Hope it was clear and concise. A solution would be great, if not please give me good starting pointers.

Second update : According to the suggestion below I have made some progress. As you can see in the code below, I am able to now save the image, but i am still unable to echo out the output image as a download prompt. Please suggest a correction.

$filename = uniqid();
$file = 'uploads/'.$filename.'.jpeg';   
$final_image = imagejpeg($new, $file, 100);
$size = filesize($file); 

header("Content-Type: application/force-download; name=\"" . basename($file). "\""); 
header("Content-Transfer-Encoding: binary"); 
header("Content-Length: $size"); 
header("Content-Disposition: attachment; filename=\"" . basename($file) . "\""); 
header("Expires: 0"); 
header("Cache-Control: no-cache, must-revalidate"); 
header("Pragma: no-cache"); 
readfile($file); 
unlink($file);

Third Update : Found out that I can use relative paths so I dont need to load wordpress load.php, changed the code accordingly. Issue still remains.

Fourth Update : Tried this code as suggested in solutions in this thread. Same result, prints out gibberish instead of offering a download link. This is getting frustrating, I must be getting close :).

Final Update : There was javascript parsing the output of the script, so I was getting all gibberish. I removed it now everything is okay.

Sidux · Accepted Answer · 2013-10-30T11:16:12.680

1

I think one solution is that you save the image in your server with imagejpeg() after that force download and delete the file you will have something like this :

$img = imagejpeg($resource, $file);
$size = filesize($file); 
header("Content-Type: application/force-download; name=\"" . basename($file). "\""); 
header("Content-Transfer-Encoding: binary"); 
header("Content-Length: $size"); 
header("Content-Disposition: attachment; filename=\"" . basename($file) . "\""); 
header("Expires: 0"); 
header("Cache-Control: no-cache, must-revalidate"); 
header("Pragma: no-cache"); 
readfile($file); 
unlink($file); //to delete the file that you generated

where $file is the file path the unlink function to delete that file.

You can also force download directly like this :

    header("Content-Disposition: attachment; filename=\"titleimg\";");
    header('Content-Type: image/jpeg');
    imagejpeg($im);
    imagedestroy($im);

Regards,

edited Oct 30 '13 at 11:16

answered Oct 30 '13 at 10:56

Sidux

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the second block of code prints out gibberish instead offering a link. Still trying to figure out the first one. – gurung Oct 30 '13 at 11:57
try to test with is_directory, is your path relative to your script? a hint : use __DIR__ constant to get your current script direction – Sidux Oct 30 '13 at 15:12
path is not an issue anymore, I have solved it. Please check my efforts update in progress, as you can see i have adapted your code from the first block. But it just outputs jibberish and does not prompt a download at all. – gurung Oct 30 '13 at 15:20
There was javascript parsing the output of the script, so I was getting all gibberish. I removed it now everything is okay. But although you solution ( first code block ) works, the image downloaded does not display on windows photo viewer and shows display error while trying to open in firefox. – gurung Oct 31 '13 at 07:30

Force a download link once image is resized

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