With exponential growth in demand for digital video content and emergence of OTT players, piracy of online content has become one of the largest threats to content creators, providers, broadcasters, and operators. When content is leaked after decryption, digital rights management (DRM) and conditional access system (CAS) technologies do not help. In such a scenario, forensic watermarking of video content provides an effective solution. While video watermarking solutions cannot directly prevent piracy, they enable content providers to detect it and take action against those involved in it.
Forensic watermarking embeds pre-defined data (a set of characters or a code) within media chunks. This data is difficult to obfuscate, alter, or erase without unacceptably damaging the host media itself. This ensures that the data travels with the media all along its distribution network and copy operations. Often information about the distributor or the subscriber of the content is embedded in the distribution chain. If the content is pirated or redistributed, the copyright information is extracted from the watermarked data, which can be traced back to find the source of piracy, and necessary action can be taken. Extraction approaches are called “non-blind” if the original content is required, “informed” if some of the information is needed, and “blind” if the original content is not needed at all. While blind extractions are the easiest to deploy, non-blind approaches increase the effectiveness of the mark as the original, unmarked content will not be accessible to a pirate.
Once the source of the leakage is detected using the operator or subscriber mark of video watermarking, multiple sets of actions can be taken against the use and further distribution of illegal video content as well as to prevent further leakages. One approach is to gather information about the location, frequency, and timing from the leaked content so as to take an informed decision. This data can also be correlated with billing systems to identify suspicious transactions. An operator could then immediately take down the infringing stream and users suspected of piracy could be given limited access or their accounts could be suspended. The final step is to take legal action against unauthorized users. Some content owners also employ manual identification or content fingerprinting to detect infringement on the internet. Take-down tools and notices are then sent to the relevant parties including ISPs and CDNs.