Copy Protection

Copy Protecting CD/DVD or USB Flash Drive Pros & Cons:

Many publishers sell their intellectual property on CD, DVD, or USB thumb (flash) drives. Understandably, they want to protect their content from those that would copy their files and distribute them to others. At the same time, they do not want to limit the user experience. Thus, some publishers ask whether TrepStar offers copy protection. We have decided not to offer copy protection for several reasons. It does not work well and creates more problems than it solves.

Problem Overview:

In a perfect world, you would load the USB flash drive (or CD/DVD) on your computer or smart TV and the user could view the files in any way they wish but would not be able to copy them (Windows explorer or Mac finder). Some Video DVDs are harder to copy because they contain several files, but it's very easy for anyone to make a .ISO image file of the DVD which is a copy of the entire contents in a single file. Unfortunately, there is no way to effectively copy protect USB flash drives (or other media) without radically changing the file(s), making the end product much less useful.

Computers, or other smart TVs or devices need to read the data (mp4, wav, mp3, ,jpg, png, doc, pdf ...) from the DISC or USB into memory so the viewer application can view or play the file. Once your file is in memory it can be copied. There is no way to restrict any of these programs from doing a file-save as... to copy the file to anywhere on their device or network, or dropbox etc.

These are some of the most common software applications that can read/view different types of files:

  1. Video: Windows Media Player, VLC media player (.iso, .mov, .avi, .mp4)
  2. Audio: iTunes, Windows Media Player (.mp3, .wav)
  3. Documents: Adobe Acrobat PDF viewer, MS Word, Xcel etc. (.pdf, .doc, .xls, .ptt)
  4. Images: Photoshop, Paint, Paint Shop Pro (.jpg, .gif, .png)

File permissions are not the answer:

If software has read access to a file, it means Windows explorer (or Mac finder) can read the file into memory (a copy), which then can be pasted as a new file. This means file level permissions do not work because read access is all it takes for any file to be copied. You might prevent a file from being overwritten on the USB drive itself, but that's it. In other words, there is no way to prevent finder or explorer from doing a simple copy/paste without preventing the file from being used at all!

Partial Solution:

The most common attempt to solve the copy protection problem is to take the source file(s) and encapsulate them inside a read only .EXE file that will not run on any other drives or device. The Flash drive hardware ID and other information is used to verify whether the file can run or not. When the user gets the DISC or USB, they have to click on the .EXE file to run it (using finder or explorer). When they do, they are presented with a menu or folder view. After selecting a file, the EXE itself has a built in viewer for that type of file. This EXE viewer is often confusing to use, has limited capability, and has limited use on specific devices (i.e. will not work on a smart TV with a USB port).

The problem with this method is that this EXE file must contain its own version of a reader/viewer for each type of file. In other words, if you have a .jpg image, the EXE contains an image viewer that can display the .jpg file stored inside the EXE. This viewer would have no file-save or file-print, nor would it allow you to copy anything to the clipboard. If it was an mp4 video file, windows media player or VLC media player can not open this EXE. The EXE has a limited video player built into it. You need to choose whether the file is for use on a Mac or PC, and this file can not be used in any other devices (like a smart TV).

Problems with this solution:

There are many drawbacks to the EXE method:

  1. It drastically increases the file size of certain types of files because a viewer program is part of the EXE.
  2. The EXE will only work on a Mac or PC. You have to decide in advance which platform the target USB must be run on. A USB drive would not work in a smart TV for example. If you originally had an mp4 file, the TV can no longer play it because it can not execute the EXE file (it's not a PC or Mac).
  3. Each single file of your product needs to be configured for how it should be accessed in the final EXE file (i.e. can it be printed?, copied to the clipboard?).
  4. This is a custom setup process would cost $100.00 or more since TrepStar would have to configure your files manually. If you have many files, it would cost many hundreds of dollars, especially if you have many different types of files and different rules for how they need to be limited.
  5. There would be an additional charge for each unit manufactured by TrepStar because licensing costs are based on how many flash drives are protected, not on one time license fee.


Because of all of these drawbacks, TrepStar has decided not to offer copy protection for CD/DVD/USB flash drives. If there was a good solution, we would offer it, but there is not. For those publishers that still insist it's imperative to have copy protection, we fear this is a classic case of "throwing the baby out with the bathwater", or "not seeing the forest for the trees".

In actuality, losses of this nature (copying files that a person has actually paid money for) does not happen as often as you may think. Research shows people who pay good money for your product are not just going to give it away free to the next guy that wants it. We all know it's theft. Sure, your customer may copy your files to a few of their own computers or devices but you will not see a real reduction in revenue because most people will not pay for more than one copy anyway. The customer wants to be able to use the files for their own use.

Have you ever purchased music from iTunes? Do you just give away all of your MP3 files to your buddy if they ask you? No, you think to yourself "Go buy them yourself!"

Yes, some people may copy files for some other individuals. However, any missed revenue is likely offset by initial setup costs, higher unit costs and loss of potential repeat customers, not to mention bad product reviews. And you will lose customers. Doing copy protection generally infuriates all of your honest customers and limits them from fully utilizing what they thought they paid for. Using copy protection is a big turn off for the 99% of users that will never think to give away your product to someone else for free when they had to pay for it.

The Big Picture:

Instead of solving a problem, you will create a bigger one: You will create angry customers. The following is a forum entry discussing the possibility of copy protecting USB Flash drives. The conclusion of our research is that it can not be done well, and it really upsets your good, almost always honest, paying customer.

John R.
Re: OT: Prevent copying of USB's containing MP4 videos possible?
by John R.
on Dec 15, at 9:11:56 pm

[Nigel O'N] "I am beginning to think it cannot be done."

You are correct that you can't do this.

...and if you did, I would never buy a video from you just like I would never buy a video from Amazon because they add copy protection that limits where I can watch the video. I have videos from Amazon that are locked to an old PC that I don't even own anymore. What a complete waste of money. People buy MP4's because they want to watch them on any device they own. ...

I have purchased videos of my daughter's dance competitions where DVD's were $19 and HD Digital Copy was $30 and I would always pay the $30 and get a USB with a digital copy that I could then play on my phone, or media server, or wherever.