View Item 
        •   Utrecht University Student Theses Repository Home
        • UU Theses Repository
        • Theses
        • View Item
        •   Utrecht University Student Theses Repository Home
        • UU Theses Repository
        • Theses
        • View Item
        JavaScript is disabled for your browser. Some features of this site may not work without it.

        Browse

        All of UU Student Theses RepositoryBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

        Generating AUs on Faces Utilizing ChatGPT Image Generation Models to Improve Performance and Fairness in AU Detection

        Thumbnail
        View/Open
        Thesis__final_final_for_sure.pdf (13.65Mb)
        Publication date
        2025
        Author
        Pereira, Orane
        Metadata
        Show full item record
        Summary
        This thesis explores whether a gender and ethnicity balanced synthetic dataset of facial images, generated with the ChatGPT-Image-1 API, can improve both performance and subgroup fairness in Facial Action Unit (FAU) detection. First, 40 high-resolution neutral identities evenly split across gender (20 male, 20 female) and across four ethnic groups (Black, Brown, Asian, White) are created. For each identity 25 AU-rich expressions are synthesized, yielding a dataset of 1,040 images (40 neutral + 1,000 expression frames). This data is used to fine-tune a FMAE-IAT AU-detector fine-tuned on BP4D dataset. Two fine-tuning regimes are evaluated: (i) an imbalanced real-world baseline (BP4D), (ii) an imbalanced real-world baseline (BP4D) and a synthetic dataset. F1 and AUC scores are used to measure overall and cross demographic performance, while FID is used to measure the realism of the generated dataset.
        URI
        https://studenttheses.uu.nl/handle/20.500.12932/50328
        Collections
        • Theses
        Utrecht university logo