Abstract:Wildlife monitoring via camera traps has become an essential tool in ecology, but the deployment of machine learning models for on-device animal classification faces significant challenges due to domain shifts and resource constraints. This paper introduces WildFit, a novel approach that reconciles the conflicting goals of achieving high domain generalization performance and ensuring efficient inference for camera trap applications. WildFit leverages continuous background-aware model fine-tuning to deploy ML models tailored to the current location and time window, allowing it to maintain robust classification accuracy in the new environment without requiring significant computational resources. This is achieved by background-aware data synthesis, which generates training images representing the new domain by blending background images with animal images from the source domain. We further enhance fine-tuning effectiveness through background drift detection and class distribution drift detection, which optimize the quality of synthesized data and improve generalization performance. Our extensive evaluation across multiple camera trap datasets demonstrates that WildFit achieves significant improvements in classification accuracy and computational efficiency compared to traditional approaches.
Abstract:While existing strategies for optimizing deep learning-based classification models on low-power platforms assume the models are trained on all classes of interest, this paper posits that adopting context-awareness i.e. focusing solely on the likely classes in the current context, can substantially enhance performance in resource-constrained environments. We propose a new paradigm, CACTUS, for scalable and efficient context-aware classification where a micro-classifier recognizes a small set of classes relevant to the current context and, when context change happens, rapidly switches to another suitable micro-classifier. CACTUS has several innovations including optimizing the training cost of context-aware classifiers, enabling on-the-fly context-aware switching between classifiers, and selecting the best context-aware classifiers given limited resources. We show that CACTUS achieves significant benefits in accuracy, latency, and compute budget across a range of datasets and IoT platforms.