H3 Segment Sampling Start

easy h3SegmentSamplingStart is the least impressive-sounding node in the Easy-Media pack: it takes in the five things a sampler needs, and hands all five straight back out untouched. It doesn't denoise, doesn't reshape, doesn't change a single value. What it does is sit exactly where the easy multitrackProject graph begins sampling a segment, and announce it. When you're running a 12-segment H3 project and want to know whether it's currently on segment 4's first pass or segment 7's second pass, this node is how you know.

What it does

Two things, both observational:

1. Notifies the frontend. It fires the project-refresh event with the project name, segment index, and sampling pass, so the MultiTrack Project widget's preview can update before generation starts. That's how the UI shows "about to sample segment 5 (second pass)" instead of sitting frozen.
2. Logs to the console. It reads the sampler's name and the sigmas schedule and prints them with a MultiTrack Project tag - useful when you're debugging why a segment came out noisy (the sigmas you thought were being used often aren't the ones in the log).

That's it. The inputs (noise, guider, sampler, sigmas, latent_image) plus the bookkeeping ones (project_name, segment_index, sampling_pass, and an optional previous pass-through) all come back out the same-named outputs in the same order. previous is there purely so the node can be threaded into a chain without breaking it.

Why a no-op node exists

ComfyUI caches aggressively and only reruns nodes whose inputs changed. A project that samples the same segment twice in a row needs something that forces a fresh notification each time - that's why this node is marked dev-only and non-idempotent. It's an instrumentation point, deliberately placed in the expanded graph so the pipeline has a stable hook between encoding and sampling. If you inspect your queue and see it, that's not clutter; it's the pipeline's heartbeat.

You won't wire one into your own graph - it's internal to the project expansion, and there's no benefit to a hand-built workflow. Its value is diagnostic: when a segment misbehaves, the "MultiTrack Project: Sampling segment ..." line in the console tells you exactly which pass and with which sampler/sigmas, which is more than most orchestrator nodes give you.

Installation

Part of ComfyUI-Easy-Media, installed like everything else in the pack:

# FFmpeg first (the README's hard requirement)
cd ComfyUI/custom_nodes
git clone https://github.com/yolain/ComfyUI-Easy-Media

Restart ComfyUI or install via Manager (search "ComfyUI-Easy-Media"). No models, no dependencies - it's a logging pass-through.

Troubleshooting

• The project preview freezes during sampling - if the frontend notification can't reach the UI (e.g. running headless), the node silently skips it and sampling continues. That's by design; check the console for the log line instead.
• You see it in your workflow and don't know why - it arrived via the project node's expansion. It's safe to leave; bypassing it doesn't change sampling, only the progress reporting.

Honestly, if you never think about this node again, it's working. It's the pipeline telling you it's alive - and when things go wrong, it's the first place to look.