Server Side Watermarking for User-Specific Forensic Tracking
Verimatrix, a global leader in the practical application and commercialization of forensic video watermarking solutions, has added patent pending StreamMark™ to its technology portfolio of revenue protection innovations. This forensic watermarking technology that has been specifically developed to support a highly efficient server-side embedding process to uniquely mark compressed and possibly encrypted content files during delivery. Mass delivery of uniquely marked content offers a valuable tool to combat revenue leakage in the latest video consumption models, such as over-the-top (OTT) delivery to standard CE devices including games consoles, Blu-ray players, connected TVs, PCs and mobile devices, as well as pre-DVD release content on pay-TV networks. Integration in the head end is an important alternative to client side watermarking like as it does not require any control or modification on the client side.
Forensic watermarking also offers pay-TV operators new revenue opportunities by enabling access to premium HD and on-demand content for “early release window” (ERW) services, the timing of which runs in parallel with the theatrical release. Studios offering content for the ERW require digital watermarking together with encryption and Selectable Output Control. Verimatrix has been working with the studios for several years and offers a technical solution that is trusted for ERW services.
StreamMark® embeds transaction unique, forensic tracing information in digital content before delivery to each client device. The current version of StreamMark® supports MPEG-2 and MPEG-4/AVC content in MPEG-2 Transport Stream or MPEG-4 ISO file format. The embedding process is architected to have extremely low overhead - to the point where it can be easily added as a component of stream based media delivery environments with negligible performance impact. It enables the embedding of a robust, secure and imperceptible transaction or customer identifier in compressed and encrypted content before distribution to standard decoders and media players in STBs, PCs and mobile devices.
The embedding principle is based on conditional removal of video information and efficient replacement with alternative information using alternative data that is pre-calculated once per content. This technique can be efficiently applied in compressed – and possibly encrypted – file or stream formats. The resulting stream can be decrypted, decompressed and rendered by standard media player devices – hardware or software. All downstream copies of compressed or re-recorded media will contain the unique payload identifier, which can be extracted by systematic, machine aided comparison with the original content, even after severe distortion or degradation. StreamMark is a simple, robust and powerful solution to tracing illegitimate copies of online digital content.
The Verimatrix/Reveal™ Service is offered in order to extract and interpret the embedded payload, thus providing convenience for VideoMark and StreamMark® customers and, importantly, security against arbitrary verification.
To get a perspective on how these watermarking technologies can be applied further, please download the Verimatrix whitepaper “Integrated Watermarking Creates More Durable Pay-TV Businesses” or contact Verimatrix.
Verimatrix is a leading member of the Digital Watermarking Alliance.
- Pre-processing: StreamMark pre-processing is applied on the encoded, unencrypted content (MPEG-2 and MPEG-4/AVC content in MPEG-2 Transport Stream or MPEG-4 ISO file format). The content is pre-processed once at ingest time, including decoding and analysis of the media while considering factors such as compression requirements, invisibility, robustness and security variations. Locations for data replacement are identified purely through examination of the compressed bit stream, which means that video encoder integration is not required. If encryption is applied before distribution, the content as well as the generated replacement data is encrypted after pre-processing before distribution to the embedding location.
- Embedding: Payload embedding is performed on every uniquely delivered copy of the content and is driven by the analysis output from the pre-processingstep. A unique payload identifier is embedded by performing a conditional replacement with pre-determined alternative data and does notrequire decoding of media content itself. This server side or distribution network process is extremely resource efficient. In the case of pre-processed segments, the embedded process is reduced to the individual selection of the segments that uniquely identify the client device.
- Extraction: Extraction of the embedded watermark is performed through the Verimatrix StreamMark/Reveal™ Service. Suspect files to be analyzed are submitted to Verimatrix for extraction of the embedded information along with the original unmarked file as reference.
- Watermarking Properties and Robustness: StreamMark has been developed in cooperation with studios to ensure that the robustness, security and invisibility match the requirements to protect high value content. Embedded watermarks are robust against compression, camcorder capture, filtering and geometric distortions. These transformations are identified and compensated at the extraction stage in comparison with the original content.
- Invisibility: Invisibility is achieved by employing statistical and empirical perceptual models to identify marking locations during pre-processing.
- Compliance: The marked content is fully standard compliant and plays on unmodified client decoders including the robust mark.
- Security: Several layers of security prevent attacks aimed at corrupting or removing the payload. Further information on specific attacks and theirprevention is available upon request.