Header/readfile does not work when trying to display image outside of website root

What are you trying to accomplish?  Is it to render an image in the browser viewport or force a download?

Display an image located outside public_html

Ex.

<img src="/photo.php?fileid=xxxx" />

Photo.php

# Set headers
header("Cache-Control: public");
header("Content-Description: File Transfer");
header("Content-Disposition: attachment; filename=".$file['original_filename']);
header("Content-Type: application/octet-stream");
header("Content-Transfer-Encoding: binary");
header("Content-Length: ".filesize($absolute_path));

ob_clean();
flush();

# Read the file from disk
readfile($absolute_path);

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The image appear correctly in both Firefox and IE, but not in Chrome. Chrome just keep loading, no image appears.

You may have a lot more headers than you need.  This article describes how I do it.
https://www.experts-exchange.com/Web_Development/Web_Languages-Standards/PHP/A_10065-Adding-a-Watermark-to-an-Image.html

IIRC the only header you really need is Content-type

I am also a little suspicious of this.  Why do you use that function?
http://php.net/manual/en/function.ob-clean.php

Hi Ray,

Does not matter what I do, nothing loads in Chrome for me.
http://fs01.imgdrive.com/download.php?token=3L9QZB

header("Content-Description: File Transfer");
header("Content-Disposition: attachment; filename=".$file['original_filename']);
header('Content-Type: '.$file['mimetype']);

# Read the file from disk
readfile($absolute_path);

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I removed ob_flush and cleaned up the headers. Seems I need the extra two or it's not possible to save the image with original filename when right-clicking (save as).

More error checking.
http://fs01.imgdrive.com/test.php

$absolute_path = "/home/fs01/uploads/2012/12/31/v3hbspfc9d_image.jpg";

header("Content-Description: File Transfer");
header("Content-Disposition: attachment; filename=".basename($absolute_path));
header('Content-Type: application/octet-stream');

# Read the file from disk
readfile($absolute_path);

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Seems the code above start image download.
Going to see if the rest works with it.

Works not, not sure what the problem was.

header("Content-Description: File Transfer");
header("Content-Disposition: attachment; filename=".basename($absolute_path));
header('Content-Type: '.$file['mimetype']);

# Read the file from disk
readfile($absolute_path);

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