File expiration

[Dilligas]

I have looked around and hope this message is going in the right forum. Anyway, I am trying to find a method of adding a file expiration date (a date after which the file could no longer be viewed) to videos. I have looked into WMV digital rights management a little, but all that I saw there required a ongoing licensing service to manage the expirations.

For my purpose, the videos created must be posted in a downloadable and transportable format for someone to say burn onto a CD and take home with them to watch. Streaming is not an option for the foreseeable future. I am just looking for something relatively quick and dirty to add some level of protection. Even if it could be defeated by simply changing the system clock on the computer, that would still be better than what I have now.

My current system specs are Intel Core2 6300 (1.86 GHz), Windows XP, VideoStudio 11.5+ Pro, and I have been using DivX 6.8 Pro up to this point (but realize that is a dead end on DRM). I've been recording AVCHD files with a Sony HDR-SR5. Thanks for any help/advice.

[Ron P.]

I don't know of any way to embed a drop-dead script inside a video clip. These are generally handle through server-side scripts, such as PHP and Javascript. The code would check for the current date, and if it is greater then a specified value, it would not provide the download link.

I would suggest looking for some web-design, scripting forums. They should be able to give you an idea on what is needed for this.


OT
Have your snow shovel ready for tomorrow?

[heinz-oz]

Vidoman is spot on there. The problem with scripting of course is that the DVD standard does not incorporate any scripting capabilities to my knowledge.

Once burned to a DVD or CD, this disk will play indefinitely.

DRM needs ongoing licensing and is costly. Furthermore, as we all know, most DRM protection is circumvented rather quickly by hackers in any case.

[sjj1805]

Using Television as an example. They make lots of their TV programs available for download so that you can watch on your computer. Several other television Companies are doing the same thing, but I know that SKY are red hot when it comes to anti piracy systems.

They employ a system that only allows you to watch a downloaded program up until a specified date. However it goes a bit deeper, it can only be watched on THAT particular computer. Whilst you can burn it onto a DVD that DVD is only watchable on THAT computer.

I have not seen a system that allows time limited programs to be transported to another device/location to permit viewing. It would seem that the host computer must contain a hidden key file deep inside the computer somewhere.

Based upon this I would think that what you are attempting to find is not possible.

[Dilligas]

Thanks for the very useful feedback. I knew that once it was in a DVD-Video format (or VCD, etc.) there would be no hope of controlling the file. I had speculated that Microsoft might have put something quick and easy like this into their WMV format as a selling point, but full-blown, perpetual licensing seems to be all they are really gearing towards. The videos that I am publishing are taped lectures of my course to be used in an online version of the same course to be offered soon. Rural Kansas students don't always have (or can afford) high speed internet access to stream 3+ hours of lecture per week. That is why I started off with DivX to compress each 1.5 hour lecture into a <700 MB file that could be downloaded with the high-speed internet on campus, burned to a CD, and then taken home to watch. DivX gave me pretty good results on this and had the option of playing the discs on DivX-compatible DVD players as a bonus for students with ancient computers that might not be able to keep up with the compression of the file.

All that being said, I know life is a series of compromises, and what I am doing currently may be the best overall option. What prompted me to inquire further about a "drop-dead" date possibility in the file are stories about one school or individual instructors stealing online content from other institutions to build their own courses. I don't have the resources to be a copyright cop and teach at the same time. I have added an animated GIF with the school logo that pops up as a semitransparent overlay/watermark every 10 minutes or so. However, I'm not quite pleased with it. The animated GIF plays smoothly in internet explorer, etc., but it comes out quite choppy in the final VS11.5+ product. The GIF is 100 frames with 100 ms delay in-between (made with the GIMP using layers). There are days that I feel I'm being too paranoid about this, but as most people on here I feel would agree, I don't want to make it easy for someone else to unfairly profit off of my work.

vidoman: Shovel is ready, but we haven't seen anything here on the eastern edge of KS yet. Though, Fort Scott is supposed to get something out of this storm before it is all said and done.

[Ron P.]

You could try something similar to your animated GIF, with just a semi-transparent image using the PNG format, or even a short video clip, placed in an overlay track. You would need to place several copies along the time-line so that it would "pop up" every so often. The final rendered quality would be much better than a GIF. GIF uses less colors, so any further compression is going to degrade it easily. Whereas you start with something of higher-quality, when it is compressed, you stand to have a better result.

In the past I've used an image (logo) that is small, semi-transparent, but yet can be seen. I place it in the lower corner of my video clip. This image is stretched the duration of the video. Once the project is rendered, it becomes part of the video. The only way to circumvent it is to blur or block it out, which of course is noticeable. You want to make sure it is placed inside the TV safe area, otherwise the overscan will cut it off.

It's been snowing here, but the good news is, the major (5-7") area was moved on south of here. So we might get about 1-2". It's already starting to let up, and I noticed that the icicles are melting, so the temps staying up there, which of course will add to the melting of any snow.. I think your area was also in that band of heavy snow that we were to receive. IIRC, you're only about 50 miles NE from here..

[Dilligas]

Actually, the image quality on the animated GIF is fine for what I need. The animation is what goes from smooth (viewed in IE or other photo viewers) to very choppy (temporal) once rendered.