Moonwalk: Advancing Gait-Based User Recognition on Wearable Devices with Metric Learning

*=Equal Contributors
Personal devices have adopted diverse authentication methods, including biometric recognition and passcodes. In contrast, headphones have limited input mechanisms, depending solely on the authentication of connected devices. We present Moonwalk, a novel method for passive user recognition utilizing the built-in headphone accelerometer. Our approach centers on gait recognition; enabling users to establish their identity simply by walking for a brief interval, despite the sensor’s placement away from the feet. We employ self-supervised metric learning to train a model that…Apple Machine Learning Research

Merge Vision Foundation Models via Multi-Task Distillation

As the repository of publicly available pre-trained vision foundation models (VFMs) — such as CLIP, DINOv2, and SAM — grows, users face challenges in storage, memory, and computational efficiency when deploying multiple models concurrently. To address these concerns, we introduce a unique approach that merges the capabilities of multiple VFMs into a single efficient multi-task model. Our method, termed “joint distillation,” seamlessly integrates teacher-student learning with self-distillation, operating with just unlabeled image data and drastically cutting down on computational requirements…Apple Machine Learning Research

Vision-Based Hand Gesture Customization from a Single Demonstration

Hand gesture recognition is becoming a more prevalent mode of human-computer interaction, especially as cameras proliferate across everyday devices. Despite continued progress in this field, gesture customization is often underexplored. Customization is crucial since it enables users to define and demonstrate gestures that are more natural, memorable, and accessible. However, customization requires efficient usage of user-provided data. We introduce a method that enables users to easily design bespoke gestures with a monocular camera from one demonstration. We employ transformers and…Apple Machine Learning Research

VeCLIP: Improving CLIP Training via Visual-enriched Captions

Paper abstract: Large-scale web-crawled datasets are fundamental for the success of pre-training vision-language models, such as CLIP. However, the inherent noise and potential irrelevance of web-crawled AltTexts pose challenges in achieving precise image-text alignment. Existing methods utilizing large language models (LLMs) for caption rewriting have shown promise on small, curated datasets like CC3M and CC12M. This study introduces a scalable pipeline for noisy caption rewriting. Unlike recent LLM rewriting techniques, we emphasize the incorporation of visual concepts into captions, termed…Apple Machine Learning Research

Human Following in Mobile Platforms with Person Re-Identification

Human following serves an important human-robotics interaction feature, while real-world scenarios make it challenging particularly for a mobile agent. The main challenge is that when a mobile agent try to locate and follow a targeted person, this person can be in a crowd, be occluded by other people, and/or be facing (partially) away from the mobile agent. To address the challenge, we present a novel person re-identification module, which contains three parts: 1) a 360-degree visual registration process, 2) a neural-based person re-identification mechanism by multiple body parts – human faces…Apple Machine Learning Research

What Can CLIP Learn From Task-specific Experts?

This paper has been accepted to the UniReps Workshop in NeurIPS 2023.
Contrastive language image pretraining has become the standard approach for training vision language models. Despite the utility of CLIP visual features as global representations for images, they have limitations when it comes to tasks involving object localization, pixel-level understanding of the image, or 3D perception. Multi-task training is a popular solution to address this drawback, but collecting a large-scale annotated multi-task dataset incurs significant costs. Furthermore, training on separate task specific…Apple Machine Learning Research

Privacy-Preserving Quantile Treatment Effect Estimation for Randomized Controlled Trials

In accordance with the principle of “data minimization,” many internet companies are opting to record less data. However, this is often at odds with A/B testing efficacy. For experiments with units with multiple observations, one popular data-minimizing technique is to aggregate data for each unit. However, exact quantile estimation requires the full observation-level data. In this paper, we develop a method for approximate Quantile Treatment Effect (QTE) analysis using histogram aggregation. In addition, we can also achieve formal privacy guarantees using differential privacy.Apple Machine Learning Research

Multichannel Voice Trigger Detection Based on Transform-average-concatenate

This paper was accepted at the workshop HSCMA at ICASSP 2024.
Voice triggering (VT) enables users to activate their devices by just speaking a trigger phrase. A front-end system is typically used to perform speech enhancement and/or separation, and produces multiple enhanced and/or separated signals. Since conventional VT systems take only single-channel audio as input, channel selection is performed. A drawback of this approach is that unselected channels are discarded, even if the discarded channels could contain useful information for VT. In this work, we propose multichannel acoustic…Apple Machine Learning Research

SynthDST: Synthetic Data is All You Need for Few-Shot Dialog State Tracking

In-context learning with Large Language Models (LLMs) has emerged as a promising avenue of research in Dialog State Tracking (DST). However, the best-performing in-context learning methods involve retrieving and adding similar examples to the prompt, requiring access to labeled training data. Procuring such training data for a wide range of domains and applications is time-consuming, expensive, and, at times, infeasible. While zero-shot learning requires no training data, it significantly lags behind the few-shot setup. Thus, ‘Can we efficiently generate synthetic data for any dialogue schema…Apple Machine Learning Research