High-Speed Full-Color HDR Imaging via Unwrapping Modulo-Encoded Spike Streams

2026-04-16

AI Summary

Traditional multi-exposure HDR imaging is prone to motion artifacts, while single-shot approaches suffer from irreversible information loss. Existing modulo-based sensor solutions are hindered by the computational overhead of iterative phase unwrapping and hardware limitations, making it difficult to simultaneously achieve high speed and full-color HDR reconstruction. This work proposes a complete modulo-encoded HDR imaging system that leverages an exposure-decoupled modulo imaging model to enable temporally interleaved measurements and introduces a non-iterative unwrapping algorithm fusing diffusion-based generative priors with the physical property of minimal absolute residues in modulo images. The authors present the first pulse-stream-based modulo HDR hardware prototype, achieving 1000 FPS full-color HDR imaging on dynamic scenes while reducing output bandwidth from approximately 20 Gbps to 6 Gbps, thereby significantly alleviating system-level bottlenecks.

Technology Category

• Computer Vision: Multi-modal Vision
• Machine Learning: Multimodal Learning
• Intelligent Robots: Multimodal Perception & Sensor Fusion

Application Category

• Search and Retrieval-Augmented AI: Retrieval-Augmented Generation (RAG) and multi-modal RAG
• Systems and Infrastructure for Web, Mobile and WoT: Data management and stream processing for Web, mobile and wireless applications
• Security and Privacy: Data transparency and provenance

Abstract

Conventional RGB-based high dynamic range (HDR) imaging faces a fundamental trade-off between motion artifacts in multi-exposure captures and irreversible information loss in single-shot techniques. Modulo sensors offer a promising alternative by encoding theoretically unbounded dynamic range into wrapped measurements. However, existing modulo solutions remain bottlenecked by iterative unwrapping overhead and hardware constraints limiting them to low-speed, grayscale capture. In this work, we present a complete modulo-based HDR imaging system that enables high-speed, full-color HDR acquisition by synergistically advancing both the sensing formulation and the unwrapping algorithm. At the core of our approach is an exposure-decoupled formulation of modulo imaging that allows multiple measurements to be interleaved in time, preserving a clean, observation-wise measurement model. Building upon this, we introduce an iteration-free unwrapping algorithm that integrates diffusion-based generative priors with the physical least absolute remainder property of modulo images, supporting highly efficient, physics-consistent HDR reconstruction. Finally, to validate the practical viability of our system, we demonstrate a proof-of-concept hardware implementation based on modulo-encoded spike streams. This setup preserves the native high temporal resolution of spike cameras, achieving 1000 FPS full-color imaging while reducing output data bandwidth from approximately 20 Gbps to 6 Gbps. Extensive evaluations indicate that our coordinated approach successfully overcomes key systemic bottlenecks, demonstrating the feasibility of deploying modulo imaging in dynamic scenarios.

Problem

• HDR imaging
• modulo imaging
• motion artifacts
• single-shot capture
• high-speed imaging

Innovation

• modulo imaging
• HDR reconstruction
• spike camera
• iteration-free unwrapping
• diffusion prior