Lightator: An Optical Near-Sensor Accelerator with Compressive Acquisition Enabling Versatile Image Processing

Mehrdad Morsali; Brendan Reidy; Deniz Najafi; Sepehr Tabrizchi; Mohsen Imani; Mahdi Nikdast; Arman Roohi; Ramtin Zand; Shaahin Angizi

arXiv · 2403.05037

Lightator: An Optical Near-Sensor Accelerator with Compressive Acquisition Enabling Versatile Image Processing

Mehrdad Morsali·Brendan Reidy·Deniz Najafi·Sepehr Tabrizchi·Mohsen Imani·Mahdi Nikdast·Arman Roohi·Ramtin Zand·Shaahin Angizi

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Abstract

This paper proposes a high-performance and energy-efficient optical near-sensor accelerator for vision applications, called Lightator. Harnessing the promising efficiency offered by photonic devices, Lightator features innovative compressive acquisition of input frames and fine-grained convolution operations for low-power and versatile image processing at the edge for the first time. This will substantially diminish the energy consumption and latency of conversion, transmission, and processing within the established cloud-centric architecture as well as recently designed edge accelerators. Our device-to-architecture simulation results show that with favorable accuracy, Lightator achieves 84.4 Kilo FPS/W and reduces power consumption by a factor of ~24x and 73x on average compared with existing photonic accelerators and GPU baseline.

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BibTeX RIS

Mehrdad Morsali, Brendan Reidy, Deniz Najafi, Sepehr Tabrizchi, Mohsen Imani, Mahdi Nikdast, Arman Roohi, Ramtin Zand, Shaahin Angizi. 2024-03-08. Lightator: An Optical Near-Sensor Accelerator with Compressive Acquisition Enabling Versatile Image Processing. https://arxiv.org/abs/2403.05037

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