Weatherproofing Retrieval for Localization with Generative AI and Geometric Consistency (2402.09237v1)

Abstract: State-of-the-art visual localization approaches generally rely on a first image retrieval step whose role is crucial. Yet, retrieval often struggles when facing varying conditions, due to e.g. weather or time of day, with dramatic consequences on the visual localization accuracy. In this paper, we improve this retrieval step and tailor it to the final localization task. Among the several changes we advocate for, we propose to synthesize variants of the training set images, obtained from generative text-to-image models, in order to automatically expand the training set towards a number of nameable variations that particularly hurt visual localization. After expanding the training set, we propose a training approach that leverages the specificities and the underlying geometry of this mix of real and synthetic images. We experimentally show that those changes translate into large improvements for the most challenging visual localization datasets. Project page: https://europe.naverlabs.com/ret4loc

• The paper introduces Ret4Loc, which enhances landmark retrieval by integrating synthetic weather-varied data with geometric consistency filtering.
• It leverages generative AI to produce realistic image variants that simulate environmental changes, thereby boosting training robustness.
• Experimental results show significant improvements in localization accuracy on challenging benchmarks, validating the method’s practical impact.

Weatherproofing Retrieval for Localization with Generative AI and Geometric Consistency

Introduction to Ret4Loc

Visual localization serves as a cornerstone in autonomous systems, enabling precise navigation and interaction within variable environments. The technique capitalizes on image retrieval to approximate the pose of a camera, a process pivotal to localization precision. Nevertheless, retrieval flounders under diverse conditions, notably in the face of weather and temporal alterations, undercutting the accuracy of localization. This necessitates an enhanced retrieval phase, specifically engineered for the localization task at hand. To address this, we introduce Ret4Loc, a nuanced training methodology that synthesizes data variants and employs geometric consistency for data filtering and sampling, thereby improving the robustness of models against environmental changes.

Enhancements in Training for Visual Localization

Ret4Loc starts with the cornerstone of landmark retrieval, enhancing the training process with rigorous data augmentation and addressing domain shifts pertinent to localization, such as changes in weather, season, and time of day. Leverage is taken from the generative capabilities of AI, encoding challenging conditions in textual prompts to synthesize realistic image variants. These synthetic variants, when combined with real images, provide a diversified training set designed to instill resilience in retrieval models against environmental changes.

The methodology doesn't merely stop at augmenting data. Acknowledging that generative models might not steadfastly preserve location-specific information, Ret4Loc integrates a geometric consistency score. This score helps in sieving through synthetic data, ensuring that only beneficial variants are retained for training. It's a step further in ensuring that the augmented data contributes positively to the model's ability to generalize across varied conditions without compromising the integrity of the spatial information.

Experimental Validation and Findings

Ret4Loc's efficacy is thoroughly vetted across multiple challenging visual localization and place recognition benchmarks. The results unequivocally indicate significant enhancements in localization accuracy, attesting to the utility of synthetic data variants and geometric consistency in cultivating robust visual localization models. The approach is not just theoretical; it brings practical benefits to the field of visual localization, pushing the boundaries of what's achievable with current retrieval models.

Implications and Future Directions

This work embodies a significant stride in harmonizing generative AI with visual localization tasks. By synthesizing training variants aligned with real-world challenges and incorporating geometric filters, Ret4Loc demonstrates a pathway to achieving robustness in environmental variances, an aspect critical for autonomous systems' reliability. It opens avenues for future explorations into generative AI's role in enhancing model robustness, extending beyond visual localization to other domains where environmental variability poses a challenge.

Furthermore, it underscores the importance of geometric consistency as a criterion for validating the utility of synthesized data, hinting at broader applications in data augmentation practices across various AI domains. The journey through Ret4Loc's development is not just about overcoming current limitations in visual localization but also about setting a precedent for future research in the intersection of generative AI and task-specific model training. Ret4Loc, while a significant leap forward, is just a step in the expansive terrain of possibilities that lie in marrying generative AI with domain-specific challenges.