If someone can view an image or video in their browser then they have, by definition, downloaded it. That's how the web works - it is client server based. Whatever you can view in your browser client has been transfered to your computer from the remote website server. You didn't really say, but I'm guessing you are having problems with people deep linking into your content. If that's the case, and you are open to server side code, I believe this might work:. But it's a general outline of a workable process which might help you prevent users from deep linking.
You can overlay images with a transparent div , which will prevent people from right clicking on them or, setting the background of a div to the image will have the same effect. If you're worried about cross-linking ie, other people linking to your images, you can check the HTTP referrer and redirect requests which come from a domain which isn't yours to "something else".
It also doesn't hurt to watermark your images with Photoshop or even in Lightroom 3 now. Make sure the watermark is clear and in a conspicuous place on your image. That way if it's downloaded, at least you get the advertising! No it's not. You may block right-clicks and simillar stuff but if someone wants to download it, he will do so, trust me ;. As soon as they view your page that includes the picture or video, the item is downloaded into the temporary folder of their browser.
So if you don't want it downloaded, don't post it. You can mark folders or files so that they don't have read access any of the main web servers support this. This allows you to store them on the server without any level of access to the outside world. You may want to do this if you have a service that generates images for someone else to download later, or if you use your web account for FTP access, but don't want anyone to view the files. However, as others have said, getting into copyright areas where people can view the image or video but not save them locally is not fully possibly, although there are tools to discourage illegal usage.
Plus, it will provide a better streaming experience for your users without the need for a separate streaming server. Granted that any image the user can see will be able to be saved on the computer and there is nothing you can do about it.
Now if you want to block access to other images that the user is not supposed to see, I am actually doing it that way:. Div overlaping or background pic setting but users with little sense can easily save all resources by opening inspect element or other developer option. This will remove any click functionality from a page, but it sure stops people stealing any content! If you want only authorised users to get the content, both the client and the server need to use encryption.
For video and audio, a good solution is Azure Media Services, which has content protection and encryption. You embed the Azure media player in your browser and it streams the video from Azure. For documents and email, you can look at Azure Rights Management, which uses a special client. It doesn't currently work in ordinary web browsers, unfortunately, except for one-off, single-use codes.
I'm not sure exactly how secure all this is, however. As others have pointed out, from a security point of view, once those downloaded bytes are in the "attacker's" RAM, they're as good as gone. I think the best way is to prevent right clicking on your webpage, because that is the most convenient way a normal user try to download the content, and you can consider it as remark if u able to do this only as you are never gonna be able to stop a computer geek or hacker people from downloading it, because once the content is on the internet, it means it is in the public domain already Put the content on google drive and make it download protect.
This way people can only see your documents, pictures but cannot download it. I believe THEOplayer already provides this sort of solution as a paid service, but I'm not so sure about it. There are video hosting services such as vzaar that have this functionality. As far as I know, that will make it really hard to download directly. Stack Overflow for Teams — Collaborate and share knowledge with a private group.
Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Ask Question. Asked 12 years, 3 months ago. Active 2 months ago. Viewed k times. Improve this question. Haim Evgi Haim Evgi k 44 44 gold badges silver badges bronze badges. Do you mean require a login to access them? Or do you mean prevent them from being saved out of the browser?
I am not sure what's your purpose but if you are displaying your art works lets say, you can use Flash Galleries to make things even harder. They can do "Print Screen" stuff but still it takes time. Add a comment. Active Oldest Votes. The best of watermarks and steganographic markers are doomed to the analog hole , even if you go out of your way to secure your web server.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Ask Question. Asked 9 years, 7 months ago. Active 9 years, 7 months ago. Viewed times. Before you start answering: Client knows we can put a watermark on the images Client knows we can put image as a background using appropriate methods for cross client compatibility Any ideas? Thanks all, Fil. Improve this question.
Fillip Peyton Fillip Peyton 3, 1 1 gold badge 29 29 silver badges 57 57 bronze badges. What about 3. Client knows that if the image is visible in any manner, then people can download it and there's not a single thing that can be done to prevent it.
This is an exercise in futility. For one, if the HTML resource references a remote image, all the end user needs to do is look at the source to see where the image is located. Secondly, how are you going to stop me from pressing the PrtScn key and just taking a screen shot?
Answer: you aren't. If you have proprietary images but you still want people to see them, a watermark is your only option. Even further, you'd need one heck of a watermark to prevent me from easily photoshop-ing it out. It's not that difficult if you're fluent with any mainstream image-editor. Very lo-res images may be your best bet. And browser environments are possibly the least secure of all because if no software is installed on a device then you have no control over the actual environment so stopping screen grabbing and printing to file drivers is not possible.
See Secure Downloads for additional information on stopping downloads and copying. To stop the browser caching the PDF on the users system, they convert your PDF files to images when you upload them — so the document is no longer a PDF file but consists of just raster images. However, this provides a poor user experience since images are slow to display and print, and features such as search, bookmarks, and annotations are unlikely to be available.
However, if you encrypt a PDF file and the user does not have the decryption key to use it then it does not matter if they can download it. And if you apply DRM and licensing controls then authorized users those given access will be restricted as to what they can do with downloadable PDF files for example not being able to share them with others. Many cloud based systems claim to stop PDF forwarding — however users can share their login credentials with others so they have access to your documents anyway.
If a system uses document links then there is nothing stopping an authorized user emailing those links to other users along with the login information. Some systems state that they lock PDF files to email addresses or domains but that just means that you have to login using that email address or any email address that belongs to the domain. It does not stop PDF forwarding since authorized users can still give their login credentials to others. That is also true of 2FA codes which provide little extra protection.
A Safeguard protected PDF file can be forwarded and emailed to another user but the recipient will NOT be able to view it unless the document owner has authorized them to use it. If you are the document publisher, you can email protected PDF files to users knowing that if they fall into the wrong hands they cannot be opened. So if a protected PDF is accidentally forwarded to the wrong person they will not be able to use it. See also stop copying, downloading and emailing.
This is because there are numerous free and paid for PDF password remover programs on the Internet that will remove Adobe Acrobat permissions passwords in seconds. Users can still add comments to PDF files if you allow this option , but PDF content is always protected from editing ensuring that your original content cannot be altered in any way. In some PDF protection products, if editing is disabled you can still highlight and copy text.
Safeguard stops users from copying text and other content within a document — there is no copy paste option available and text cannot be highlighted for selection so it cannot be copied and pasted into other applications. Unfortunately there are many free screen grabbing or screen capture applications available that users can download to easily bypass this restriction. Safeguard stops screenshots being taken by common third party software applications.
It uses many different methods including a screen mask that is overlaid over the protected PDF document if the mouse cursor is moved to another active application.
No PDF DRM product however can stop all screenshots users can just take photographs of the screen so it is recommended that document publishers apply dynamic watermarks as a copying deterrent. Safeguard enables document publishers to expire PDF files so they can no longer be used after a certain amount of time.
The following options are available:. You might for example want a user to be able to use your documents for a 15 day trial period but those documents will expire on a fixed date regardless if the trial period is used or not. Being able to revoke PDF files is an important part of any document security solution.
There may be times when the wrong document was published, a user has left your company, or you think a specific document has been compromised. Safeguard enables you to revoke PDF files instantly the document must be set to check with the administration system each time it is opened , or you can revoke users so all documents they have access to become inaccessible.
If you have created PDF files that only check with the administration system every n days then PDF revocation will only take place once a check has occurred. With Safeguard, PDF files can be revoked no matter where they are located. You can also revoke access to multiple PDF files instantly and group documents into publications to make revocation easier for common groups of documents. No DRM system is fool-proof.
Even if screenshots are prevented, users can take photographs of the screen using a camera. Similarly, if printing is allowed, users can print and scan back in printed documents.
You can use different watermarks for viewed and printed documents and both text and image watermarks are supported. PDF watermarks can be displayed behind content so they are less obtrusive to the user and you can choose not to display watermarks on the first page of a document if you have a cover image that you want to leave unmarked.
See How to remove a watermark from a PDF. This is done at the user level or a global level for all users. In this way you can easily restrict all users to viewing protected PDF files from say your office location in the US. This is particularly useful if users have laptops which they are allowed to take home — locked PDF files can then only be viewed at the office and not when the user is at home or at other locations where they could be shown to others.
This is useful if you want to check whether a particular user has viewed a document yet especially if they claim to have not received it.
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