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arxiv: 2604.15255 · v2 · submitted 2026-04-16 · 💻 cs.AR · cs.SY· eess.SY

Democratization of Real-time Multi-Spectral Photoacoustic Imaging: Open-Sourced System Architecture for OPOTEK Phocus & Verasonics Vantage Combination

Ryo Murakami , Yichuan Tang , Haichong K. Zhang This is my paper

Pith reviewed 2026-05-10 09:33 UTC · model grok-4.3

classification 💻 cs.AR cs.SYeess.SY
keywords photoacoustic imagingreal-time imagingmulti-spectralopen-source systemmicrocontroller synchronizationdata streaminglaser triggersystem architecture
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The pith

An open-source architecture using a microcontroller for laser trigger counting and decoupled data streaming enables stable real-time multi-spectral photoacoustic imaging.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper presents an open-source hardware and software system designed to make real-time multi-spectral photoacoustic imaging more accessible. It addresses synchronization problems that arise when connecting fast-tuning lasers to data acquisition systems running on ordinary operating systems. The solution relies on a separate microcontroller to accurately count and manage laser triggers and a client-server setup to handle data streaming without relying on local storage. This approach reduces timing errors and storage constraints, allowing more researchers to use the technology without high costs or specialized setups. By releasing the code openly, the work aims to build a community for further development and sharing of improvements.

Core claim

By employing an independent micro-controller for deterministic laser trigger counting alongside a decoupled client-server data streaming framework, the proposed system circumvents OS-induced timing deviations and local storage bottlenecks in real-time multi-spectral photoacoustic imaging.

What carries the argument

Independent microcontroller for deterministic laser trigger counting and decoupled client-server data streaming framework that ensures precise synchronization and efficient data transfer without operating system interference.

Load-bearing premise

The microcontroller trigger counting and client-server streaming integrate reliably with the target laser and acquisition hardware without causing new synchronization problems or data loss in actual experiments.

What would settle it

Running the system during a multi-spectral imaging session with high pulse repetition rates and large data volumes while monitoring for any missed triggers, timing jitter, or dropped data packets.

Figures

Figures reproduced from arXiv: 2604.15255 by Haichong K. Zhang, Ryo Murakami, Yichuan Tang.

Figure 1
Figure 1. Figure 1: Overall architecture of the proposed RT-mPAI system. The hardware layer incorporates an independent [PITH_FULL_IMAGE:figures/full_fig_p001_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Timing and sequence diagram of the entire imaging system. The micro-controller deterministically counts [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Schematics of data packaging performed by the server instance. Both block and cyclic scanning schemes [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: Schematic of the validation setup. Blue and black wires are utilized as point targets. Calculating the signal [PITH_FULL_IMAGE:figures/full_fig_p006_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: Validation of the real-time wavelength identification pipeline. The spectrum acquired via the proposed [PITH_FULL_IMAGE:figures/full_fig_p007_5.png] view at source ↗
read the original abstract

Real-time multi-spectral photoacoustic imaging (RT-mPAI) often suffers from synchronization instabilities when interfacing fast-tuning lasers with data acquisition platforms executing on non-real-time operating systems. To overcome this, we establish an open-source hardware-software architecture tailored for the widely adopted combination of the OPOTEK Phocus lasers and Verasonics Vantage systems. By employing an independent micro-controller for deterministic laser trigger counting alongside a decoupled client-server data streaming framework, the proposed system circumvents OS-induced timing deviations and local storage bottlenecks. By open-sourcing this pipeline and cultivating a collaborative environment to share both code and ideas, we aim to lower the technical and cost barriers for RT-mPAI, thereby democratizing access to stable RT-mPAI research and, more ambitiously, fostering a vibrant open-source community.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The manuscript presents an open-source hardware-software architecture for real-time multi-spectral photoacoustic imaging (RT-mPAI) using the OPOTEK Phocus laser and Verasonics Vantage system. It employs an independent microcontroller for deterministic laser trigger counting and a decoupled client-server data streaming framework to address OS-induced timing instabilities and local storage bottlenecks, with the aim of lowering barriers to RT-mPAI research through open-sourcing and community collaboration.

Significance. If the described architecture integrates reliably and delivers the claimed stability, the work could meaningfully advance accessible RT-mPAI by providing a reproducible, low-cost open-source pipeline. The explicit commitment to open-sourcing code, designs, and ideas is a clear strength that supports reproducibility and community-driven extensions in the field.

major comments (2)
  1. [Abstract] Abstract: The central claim that the microcontroller-based trigger counting and client-server streaming circumvents OS-induced timing deviations and storage bottlenecks is load-bearing but unsupported by any quantitative validation, such as measured jitter histograms, synchronization offset statistics, or data-integrity metrics from actual multi-spectral acquisitions.
  2. [Architecture description] Architecture description: The assumption that the added microcontroller and streaming layers introduce no new synchronization offsets, communication latency, or packet loss when interfaced to the specific Phocus laser timing signals and Vantage DAQ remains untested, with no reported integration tests or error measurements under experimental conditions.
minor comments (1)
  1. The manuscript would benefit from explicit links to the open-source repository containing the microcontroller firmware, client-server code, and hardware schematics to facilitate immediate adoption and verification by readers.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their constructive and detailed feedback. We address each major comment below and have revised the manuscript to incorporate quantitative validation where the original submission was lacking.

read point-by-point responses

  1. Referee: [Abstract] Abstract: The central claim that the microcontroller-based trigger counting and client-server streaming circumvents OS-induced timing deviations and storage bottlenecks is load-bearing but unsupported by any quantitative validation, such as measured jitter histograms, synchronization offset statistics, or data-integrity metrics from actual multi-spectral acquisitions.

    Authors: We agree that the abstract's central claim requires supporting quantitative evidence. The original manuscript focused on describing the architecture and its design rationale for addressing timing and storage issues. To strengthen the work, the revised version now includes a new results subsection with measured jitter histograms, synchronization offset statistics, and data-integrity metrics collected from actual multi-spectral acquisitions on the target hardware. revision: yes

  2. Referee: [Architecture description] Architecture description: The assumption that the added microcontroller and streaming layers introduce no new synchronization offsets, communication latency, or packet loss when interfaced to the specific Phocus laser timing signals and Vantage DAQ remains untested, with no reported integration tests or error measurements under experimental conditions.

    Authors: The architecture section explains the design choices (independent microcontroller counting and decoupled streaming) intended to avoid introducing new offsets or losses. We acknowledge that explicit integration testing was not reported. The revised manuscript adds integration test results, including measured communication latencies, synchronization offsets, and packet-loss/error rates under experimental conditions with the Phocus and Vantage hardware. revision: yes

Circularity Check

0 steps flagged

No circularity: direct engineering architecture description with no derivations or reductions

full rationale

The manuscript describes an open-source hardware-software architecture for interfacing OPOTEK Phocus lasers with Verasonics Vantage systems, relying on a microcontroller for trigger counting and a client-server streaming framework. No equations, fitted parameters, predictions, or self-citations appear in the provided text or abstract. The central claim is a direct engineering proposal rather than any derivation that reduces to its own inputs by construction, making the work self-contained against external benchmarks with no load-bearing circular steps.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The work is an engineering system description with no mathematical derivations, data fitting, or postulated physical entities; it relies on standard assumptions about microcontroller determinism and network streaming reliability.

axioms (2)
  • domain assumption Microcontrollers can provide deterministic timing independent of the host operating system.
    Invoked to justify the trigger counting solution for avoiding OS-induced deviations.
  • domain assumption Client-server data streaming can eliminate local storage bottlenecks without introducing latency or packet loss under imaging data rates.
    Central to the decoupled streaming framework claim.

pith-pipeline@v0.9.0 · 5460 in / 1290 out tokens · 57140 ms · 2026-05-10T09:33:31.966354+00:00 · methodology

discussion (0)

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