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The video game scenario is a relative new scenario for the application of transactional water- marks and fingerprinting codes. The variety of different kinds of video games, its huge market and the complex and very differing composition of various multimedia components consisting in a typical video game make this watermarking scenario a research topic of its own. In fact, during the time of this thesis there is a doctoral research study in progress concerning this topic. In [12] we stated that the distribution of video games can be divided into games as a service and

games as a product.

• Games as a Service: Games as a service describes a video game that is continuously in development and purchased e.g. via a standing order. Contrary to the distribution of e.g. audio files, it is not a one time bargain, but an actively interchanging relationship between customers and developers. Typical examples are Massively Multiplayer Online (MMO) games, such as World of Warcraft (WoW), Browser Games, such as Forge of Empires, or Social Games as provided on Facebook for instance.

Due to the the Server/Client concept, to the best of our knowledge, content protection via watermarking techniques is an open challenge for which scientific watermarking has not

been applied yet. Consequently, collusion security is no issue by now and thus, games as a service are no longer considered here. We refer the interested reader to other works of our group, e.g. [12].

• Games as a Product: Games as a product describes the video games that are produced at once and, besides smaller expansions or updates now and then, are finalized with the release date. The game is purchased all at once ’in a box’ via over the counter or by down- load. This makes this branch more similar to the classical multimedia. Typical examples for games as a product are boxed game titles for PC and console platforms, e.g. The Elder

Scrolls V: Skyrim by Bethesda Softworks, Ubisoft’s Assassins Creed series and each of Rock- star Games’ Grand Theft Auto offsets. But besides there is also a huge list of Mobile Games

that can be characterized as games as a product even as they are available for free, e.g.

Rovio’s Angry Birds or Imangi Studios’ Temple Run. Certainly, the significant technical ad-

vances regarding power and performance of mobile devices have blurred the boundaries between boxed games for PC and console and boxed games liable to pay costs for mobile devices. For example, the games Real Racing 2 by EA or The Walking Dead by Telltale

Games were planned for mobile as well as PC or console games. Moreover, there are also

huge production games that are exclusively manufactured for specific mobile devices. For example, Ubisoft’s Assassin’s Creed III: Liberation is an exclusive title for Sony’s mobile plat- form Play Station Vita. This thesis confines itself to games as a product. More precisely, only classical boxed games for PC and console are considered for further investigation. This is because the classical low budget productions for mobile games are available for free, and consequently there is no market for unauthorized redistribution and thus for copyright protection including collusion security.

The development of a typical boxed video game is a process of sometimes several years. Within this time a magnitude of in-house capacities as well as professional external testers have access to the game. Additionally, specialized focus groups are hired for the testing process closely be- fore the release. All testing participants and everyone that has access have signed non disclosure agreements, hence unauthorized behavior equals committing a crime and is legally prosecuted. The watermarking scenario considering unauthorized behavior before the official release is de- voted to the promotional and pre-release scenario described in section 3.3 and elaborated in chapter 5.1.

To the best of our knowledge, the scenario of watermarking video games was primary aroused within our research group, see [12], [118], [13] and [70], in parallel to the work on collu- sion secure codes for this thesis. There is no state of the art nor practical experiences for the end-customer authentication via watermarking techniques. On first sight the watermarking de- ployment appears as obvious. As a video game inter alia consists of different components from classical multimedia, e.g. audio files and videos, in combination with rather new components (regarding watermarking) such as 3D models and texture images, deploying watermarks in each component is possible, see figure 1. Moreover, the magnitude of files of each component, e.g ca. 19000 texture images and about 3000 3D models in the video game The Elder Scrolls: Skyrim, promises huge payload for embedding. This rises new opportunities regarding the watermark- ing properties but also induces new technical challenges. One challenge is the watermarking of new cover media formats, such as Microsoft’s image compression format Direct Draw Surface (DDS) which is applied in almost every game. Another challenge is the handling of watermark- ing not only for single files as it is common in other types of multimedia, but for rather huge sets of the same cover media sometimes containing several thousands files. As the research question that is addressed for this thesis is restricted and exhausted with collusion secure fingerprinting

3D Watermarking Audio Watermarking Image Watermarking Video Watermarking Transaction ID Marked Copy

Video Game Download Customer

Store

3D Models

Music / SFX

Textures

Cutscenes

Video Watermarking Text Watermarking

Software Watermarking

Documentation

Program Code

Figure 1: A boxed video game consists of different types of media components that can be wa- termarked, based on [117]

codes and its application scenarios, the technical basis regarding video game watermarking is assumed as solid. In this thesis the focus is on the deployment of fingerprinting codes for video games. For the technical challenges regarding video game watermarking, we refer the inter- ested reader for instance to the work of [12] and to a dissertation that is elaborated in parallel to this thesis (but not published yet).

Copyright protection is as common as unpopular in the video game community. As the value of money of a typical boxed game is significantly higher than of other media goods, the market of free illegally purchasable versions is immense. The effort and costs in creating strong DRM protection mechanisms is huge. However, the so called release groups, i.e. organized groups of hackers that compete against each other in order to be the first to crack the protection, spend huge effort as well. In most cases, the result is that the protection is broken shortly after re- lease of the new game. Thus, end-customer authentication realized by watermarking methods is strongly suggested. With it, cracked versions of a game could be traced back to the respon- sible persons or parties, i.e. to the release groups. As soon as the cover of one release group is blown, the others might refrain from unauthorizedly redistributing watermarked content. Therefore, transactional watermarking technology ought to be applied in all video game com- ponents possible. Furthermore, the watermark needs to be spread over the whole content in order to exacerbate braking the protection.