Keeping Image Location Secret

Generally, when the source code of a web page is viewed, the URLs of images are visible.

If you have reason to keep the URL of an image secret, this article describes one way to do it.

One reason to keep the URL of an image secret would be to keep people from linking to your image in order to display it in their own web pages. Another reason would be to prevent people from linking to your image at their social media accounts.

Note that the method presented here works only with PHP web pages. It will not work with email reading software. PHP just doesn't work in email.

Here is an example:

To hide the image URL, make the image tag as follows (two items need to be customized).

<img
src="data:image/IMAGE_TYPE;base64,<?php echo(base64_encode(file_get_contents('IMAGE_URL'))) ?>" 
style="max-width:100%" 
alt="my image">

Two items in the format need to be replaced, IMAGE_TYPE and IMAGE_URL:

1. Replace IMAGE_TYPE with png, gif, or jpeg, depending on the type of image you will be publishing.

   You can determine the image type by the file name extension of the image to be published. If the file name extension is png (as in myimage.png) then replace IMAGE_TYPE with png. If the file name extension is gif then replace IMAGE_TYPE with gif. And, if the file name extension is jpg or jpeg then replace IMAGE_TYPE with jpeg.

2. Replace IMAGE_URL with the URL of the image to be replaced.

The image URL will not show in the web page source code because it is part of the PHP code. Anything the PHP code publishes is published with the web page. But the PHP code itself is removed from the web page when the PHP code is processed at the server.

Here is the image tag of the above example.

<img src="data:image/gif;base64,<?php echo(base64_encode(file_get_contents('https://www.willmaster.com/images/wmlogo_icon.gif'))) ?>" 
style="max-width:100%" 
alt="Willmaster logo">

After the PHP code in the above example runs, this is what would be seen in the source code of the web page.

<img src="data:image/gif;base64,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" 
style="max-width:100%" 
alt="Willmaster logo">

An img with base64-encoded data readily publishes an image in browsers. When the PHP code converts the image to base64 encoding for the web page, the URL is no longer necessary.

It is an effective method for hiding the URLs of images on the web page.

(This content first appeared in Possibilities newsletter.)

Will Bontrager