Ever wonder how illegal media uploads are taken down so quickly?

No really, can I?

For over a decade legal authorities have been fighting the same battle over and over again, thousands of times a day: taking down illegally uploaded content. The most prominent battlegrounds are YouTube and file hosting services such as Rapidshare, 4shared, Hotfile, and more. The story is the same everywhere on the internet: a user uploads a piece of content such as a video clip of a TV show or movie on YouTube and before it can hit 1,000 views it is taken down and a copyright violation notice is posted in its place. How is it that these items are found and nullified so quickly? Do the RIAA, NBC, Viacom, and other media giants have thousands of lackeys whose job is to scourge the internet for such violations? Or are the battles nothing more than man vs machine?

It would be highly impractical from a financial and resource point of view to have individuals patrol the internet for copyright violations. Instead, companies have web crawling bots that can crunch through thousands of pages per second to do their dirty work. These digital warriors do not look at the actual content of the media files themselves, but instead look for something called a digital watermark.

Digital watermarks can be both visible and invisible. They are embedded in a digital file to identify the file’s origin and copyright information. The most common type of watermark is seen on television. Most TV stations superimpose their logo in one of the corners of the screen so that if any program from that channel is recorded, the program’s origin is visibly identified. Any kind of identifier superimposed on visual content that relays ownership and copyright information is considered a visible digital watermark. This is just one type of digital watermark that crawlers will scan for on sites such as YouTube. However, visual watermarks can be easily cropped out or blurred to circumvent detection from these bots. This is why most digital files have multiple watermarks embedded in them, the most prominent being the invisible digital watermark.

Invisible digital watermarks cannot be perceived by human senses but can be detected by software programmed to do so, such as the web bots. Embedded deep into the file’s signal, this watermark cannot be removed. Recording a clip from your TV onto your computer or creating an MP3 from a CD transfers the digital watermark along with your file. When the file is uploaded to YouTube or a file sharing service the software employed by media conglomerates simply scans for this digital signature. Upon finding a file that carries that signature it reports the file as violating copyright laws and the file is promptly removed from the host’s servers. The bots are extremely efficient, which is why YouTube videos that violate copyrights are removed so quickly, even if they are not widely distributed.

Invisible digital watermarks aren’t full-proof, however. There are many ways to tamper with a watermark to make it unreadable by scanning software but these methods may result in undesirable results for the end-user obtaining the pirated copy. For example, lossy compression of audio files can degrade the watermark signal enough to make it unrecognizable, however lossy compression also degrades the sound quality of the audio file itself. Movies can be cropped or have noise added to them to distort the watermark signal, but this too results in undesirable results for the end user.

The two most popular methods for circumventing digital watermarks on YouTube is by mirroring the video or by re-capturing it via a camcorder or a cell phone. Mirroring the video fools watermark detection software since everything is backwards, although newer software is programmed to detect this. Re-capturing the video from a secondary device (such as holding a cell phone camera up to a TV screen) completely severs the digital watermark a video might possess since the video is no longer digitally copied. This is how many NFL clips exist on YouTube that are simply a DVR’d clip re-captured via a cell phone camera since the NFL is extremely notorious for taking down any user-uploaded content it has broadcast.

Anti-piracy measures are still a long way from being full-proof. With companies like Digimarc leading the hunt and organizations like the Digital Watermarking Alliance gaining members, the global cat-and-mouse game in the digital world continues with no clear end in sight. Since anti-piracy efforts have ramped up exponentially over the years a third party has been dragged into the battle: the end users. It no longer is a war between pirates and bots. It is now including skirmishes between bots and end users, with the end users racing to grab pirated content before the bots can find it and take it down. Just remember: you can always take the blue pill at any time and pay for content legally!