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- Evolving artificial terrains with automated genetic terrain programingPublication . Frade, Miguel Monteiro de SousaNowadays video game industry is facing a big challenge: keep costs under control as games become bigger and more complex. Creation of game content, such as character models, maps, levels, textures, sound effects and so on, represent a big slice of total game production cost. Hence, video game industry is increasingly turning to procedural content generation to amplify the cost-effectiveness of the efforts of video game designers. However, creating and fine tunning procedural methods for automated content generation is a time consuming task. In this thesis we detail a Genetic Programming based procedural content technique to generate procedural terrains. Those terrains present aesthetic appeal and do not require any parametrization to control its look. Thus, allowing to save time and help reducing production costs. To accomplish these features we devised the Genetic Terrain Programming (GTP) technique. The first implementation of GTP used an Interactive Evolutionary Computation (IEC) approach, were a user guides the evolutionary process. In spite of the good results achieved this way, this approach was limited by user fatigue (a common trait of IEC systems). To address this issue a second version of GTP was developed where the search is automated, being guided by a direct fitness function. That function is composed by the weighted sum of two morphological metrics: terrain accessibility and obstacle edge length. The combination of the two metrics allowed us remove the human factor form the evolutionary process and to find a wide range of aesthetic and fit terrains. Procedural terrains produced by this technique are already in use in a real video game.
- Digital Forensic Artifacts of FIDO2 Passkeys in Windows 11Publication . Domingues, Patricio; Frade, Miguel; Negrão, MiguelFIDO2’s passkey aims to provide a passwordless authentication solution. It relies on two main protocols – WebAuthn and CTAP2 – for authentication in computer systems, relieving users from the burden of using and managing passwords. FIDO2’s passkey leverages asymmetric cryptography to create a unique public/private key pair for website authentication. While the public key is kept at the website/application, the private key is created and stored on the authentication device designated as the authenticator. The authenticator can be the computer itself – same-device signing –, or another device – cross-device signing –, such as an Android smartphone that connects to the computer through a short-range communication method (NFC, Bluetooth). Authentication is performed by the user unlocking the authenticator device. In this paper, we report on the digital forensic artifacts left on Windows 11 systems by registering and using passkeys to authenticate on websites. We show that digital artifacts are created in Windows Registry and Windows Event Log. These artifacts enable the precise dating and timing of passkey registration, as well as the usage and identification of the websites on which they have been activated and utilized. We also identify digital artifacts created when Android smartphones are registered and used as authenticators in a Windows system. This can prove useful in detecting the existence of smartphones linked to a given individual.
- Digital Forensic Artifacts of the Cortana Device Search Cache on Windows 10 DesktopPublication . Domingues, Patrício; Frade, MiguelMicrosoft Windows 10 Desktop edition has brought some new features and updated other ones that are of special interest to digital forensics analysis. The search box available on the taskbar, next to the Windows start button is one of these novelties. Although the primary usage of this search box is to act as an interface to the intelligent personal digital assistant Cortana, in this paper, we study the digital forensic artifacts of the search box on machines when Cortana is explicitly disabled. Specifically, we locate, characterize and analyze the content and dynamics of the JSON-based files that are periodically generated by the Cortana device search cache system. Forensically important data from these JSON files include the number of times each installed application has been run, the date of the last execution and the content of the custom jump list of the applications. Since these data are collected per user and saved in a resilient text format, they can help in digital forensics, mostly in assisting the validation of other sources of information.
- Genetic terrain programming: an aesthetic approach to terrain generationPublication . Frade, Miguel; Fernandéz de Vega, Francisco; Cotta, CarlosNowadays there are a wide range of techniques for terrain generation, but are focused on providing realistic terrains often neglecting the aesthetic appeal. The Genetic Terrain Programming technique, based on evolutionary design with Genetic Programming, allows designers to evolve terrains according to their aesthetic feelings or desired features. This technique evolves TPs (Terrain Programmes) that are capable of generating different terrains, but consistently with the same features. This paper presents a study about the perseverance of terrain features of the TPs across different LODs (Levels Of Detail). Results showed it is possible to use low LODs during the evolutionary phase without compromising results and the terrain features generated by a TPs are scale invariant.
- Digital forensic artifacts of the your phone application in Windows 10Publication . Domingues, Patricio Rodrigues; Frade, Miguel; Andrade, Luis Miguel; Silva, João VictorYour Phone is a Microsoft system that comprises two applications: a smartphone app for Android 7+ smartphones and a desktop application for Windows 10/18.03+. It allows users to access their most recent smartphonestored photos/screenshots and send/receive short message service (SMS) and multimedia messaging service (MMS) within their Your Phone-linked Windows 10 personal computers. In this paper, we analyze the digital forensic artifacts created at Windows 10 personal computers whose users have the Your Phone system installed and activated. Our results show that besides the most recent 25 photos/screenshots and the content of the last 30-day of sent/received SMS/MMS, the contact database of the linked smartphone(s) is available in a accessible SQLite3 database kept at the Windows 10 system. This way, when the linked smartphone cannot be forensically analyzed, data gathered through the Your Phone artifacts may constitute a valuable digital forensic asset. Furthermore, to explore and export the main data of the Your Phone database as well as recoverable deleted data, a set of python scripts – Your Phone Analyzer (YPA) – is presented. YPA is available wrapped within an Autopsy module to assist digital practitioners to extract the main artifacts from the Your Phone system.
- Genetic terrain programmingPublication . Frade, MiguelNowadays there are a wide range of techniques for terrain generation, but all of them are focused on providing realistic terrains, often neglecting other aspects (e.g., aesthetic appeal or presence of desired features). This thesis presents a new technique, GTP (Genetic Terrain Programming), based on evolutionary design with Genetic Programming. The GTP technique consists of a guided evolution, by means of Interactive Evolution, accordingly to a speci c desired terrain feature or aesthetic appeal. This technique can yield both aesthetic and real TPs (Terrain Programmes) which are capable of gen- erating di erent terrains, but consistently with the same features. TPs are also scale invariant, meaning that terrain features will be preserved across di erent LODs (Levels Of Details), which allows the use of low LODs dur- ing the evolutionary phase without compromising results. Additionally, the resulting TPs can be incorporated in video games, like any other procedural technique, to generate terrains. Furthermore, by way of resorting to several TPs to compose the full landscape, it is possible to control some localised terrain features, thus eliminating the main drawback of traditional procedu- ral techniques. The combination of GP with evolutionary art systems also diminish the e ort and time required to create complex terrains when com- pared to modeling techniques. Moreover, the results are not dependent on the designer's skills.
- GenTP: uma ferramenta interactiva para a geração artificial de terrenosPublication . Frade, Miguel; Fernandéz de Vega, Francisco; Cotta, CarlosActualmente existe uma grande variedade de técnicas de geração artificial de terrenos. No entanto todas elas estão focadas em fornecer terrenos de aspecto realista, negligenciando por vezes a estética e a criatividade. Este artigo apresenta uma ferramenta interactiva para a geração artificial de terrenos, designada GenTP, inspirada nos sistemas de arte evolutiva com programação genética. Esta ferramenta permite aos designers evoluir TPs (Terrain Programs) de acordo com o seu sentido estético ou características desejadas. Os TPs, o produto desta ferramenta, geram terrenos diferentes a cada execução, mas sempre coerentes nas sua características morfológicas.
- Automatic evolution of programs for procedural generation of terrains for video games: accessibility and edge length constraintsPublication . Frade, Miguel; Fernandéz de Vega, Francisco; Cotta, CarlosNowadays the video game industry is facing a big challenge: keep costs under control as games become bigger and more complex. Creation of game content, such as character models, maps, levels, textures, sound effects and so on, represent a big slice of total game production cost. Hence, the video game industry is increasingly turning to procedural content generation to amplify the cost-effectiveness of the efforts of video game designers. However, procedural methods for automated content generation are difficult to create and parametrize. In this work we study a Genetic Programming based procedural content technique to generate procedural terrains that do not require parametrization, thus, allowing to save time and help reducing production costs. Generated procedural terrains present aesthetic appeal; however, unlike most techniques involving aesthetic, our approach does not require a human to perform the evaluation. Instead, the search is guided by the weighted sum of two morphological metrics: terrain accessibility and obstacle edge length. The combination of the two metrics allowed us to find a wide range of fit terrains that present more scattered obstacles in different locations, than our previous approach with a single metric. Procedural terrains produced by this technique are already in use in a real video game.
- Forensic Analysis of the Bumble Dating App for AndroidPublication . Barros, António; Almeida, Rafaela; Melo, Tiézer; Frade, MiguelMobile applications that facilitate interaction between people have grown in popularity and, as a result, the number of e-dating applications have expanded. In these types of applications, there is usually a trade-off between user privacy and safety. On one hand, users want to keep their data as private as possible, on the other hand, user identification forces accountability, which, hopefully, will foster the development of responsible behaviors and minimize abuses. The Bumble e-dating app has been growing in popularity and differs from other apps by giving women the power to make the first contact after a match. Their main goal is to prevent women’s harassment. In this work, we study the digital artifacts that can be found after the use of the Bumble app on Android devices. Despite applying many measures to ensure data protection, it was possible to obtain information that identifies users and exchanged messages. The data structure stored on the device is described, as well as the artifacts with forensic value for an investigation. Moreover, a script was created to parse and visualize the main forensic artifacts of the Bumble app.
- Evolution of artificial terrains for video games based on obstacles edge lengthPublication . Frade, Miguel; de Vega, F. Fernandez; Cotta, Carlos
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