How to make a restriction so that the user can view the image only once and cannot save it?

Question

Data protection

There is a visual material that needs to be shown to a person, but so that he could only watch it once, but could not save it and download it, how or what can be done? Maybe with a one-time password, or I don't know... something like that.

Answer 1

Wait for the introduction of DRM protection for images and its support in browsers, there are no other ways out, everything that the user saw on the page can be saved and seen again. Any trickiest way to break off from the camera in front of the monitor)))

Answer 2

On the web, " show " means " send to the user's device ". Therefore, your problem has no solution.
You can complicate the process of ripping out the picture, but anyone who knows how to press F12 in the browser will still be able to download it.
In addition, the question of user identification arises - how do you know that he has already viewed the image? The simplest is to write to cookies or session, but they have a limited lifetime. Yes, there is evercookie, but cookies can also be manipulated. Therefore, some other mechanism is needed. If the pictures are available only to registered users, then you can identify them and write information about viewing in the database. But if access to them is not limited by authorization, then you will either issue a picture to one client several times, or you will not issue it to some clients at all, since the definition by ip and user agent is very unreliable.
This is about pictures in a vacuum. Now describe the problem as specifically as possible so that we can advise a solution that will work most reliably (taking into account the limitations listed above).

Answer 3

Most users on the Internet will no longer be able to download an image if you insert it as a background image of some element - for example, a div. At least when you right-click on an element, there will be no such item in the drop-down menu.

Answer 4

You can put a transparent div over the image. And when you press F12 or right-click to catch the event and reload the page. After the reboot, the picture is no longer shown.

Answer 5

1) Transfer the image to canvas, it will be more difficult to save it
1.1) Break the picture into a hundred small pictures and line them up in the right order. Navryatli someone will bother to save or glue them.
2) Use one-time links. Generated a link with content given to the user, when entering the page, the link is deleted and access to it is prohibited
ps Preen Screen will bypass your protection well

Answer 6

At the moment, the only solution:
Proprietary (closed) client with a "wired" token inside with a request for content from the site. After the demonstration has passed once, we set the flag on the server: "viewed" and do not return the content on subsequent launches.

Answer 7

Gentlemen, it is immediately clear that you are programmers, not admins :) Everything will depend on the value of the information. There is such a thing as a proxy, which still stores the image in its cache - and the image file in the cache can be found, cut off the headers and renamed, although this is difficult. You can write a special client - which will pretend to be an honest viewer, and save the picture to disk.
Nobody remembers this format - RealAudio? It was a long time ago... One of the first embedded formats, which theoretically could not be downloaded either. And what - they wrote a client that was like a player, but actually saved the file to disk.
FF is full of plugins that save video from sites to disk, from which it cannot be saved. For, all this is not designed for hamsters, but the author did not provide the model of the intruder - to whom he will demonstrate this picture - to accountants or administrators.

Answer 8

Is this option suitable:
- Send the customer a USB flash drive that is encrypted and in order to view it you need to enter a password and in a special program you can see a couple of times Pictures. But it will be impossible to save them (only take a picture of the screen, because the Screenshot function at this moment will be blocked in the PC).
- Optionally, after XX days, this flash drive can already be thrown away, or given to crypto-analysts so that they dig deeper with this flash drive for 5000 usd to open the data.
If it fits, I give a link, but the software is paid :)