IDEO Image Hash Debug

There's a frustrating class of ComfyUI bug where the pipeline looks like it's changing the image but actually isn't - a cached node returns the same tensor, a crop silently no-ops, a resize lands back on the same pixels. Visually you can't tell, because the frames are near-identical. IAMCCS IdeoImageHashDebug exists to make that kind of thing visible in seconds: it's a passthrough probe that computes a hash of the image tensor and prints a report you can compare across runs.

The use case the author built it for is in the docstring: stick one after Ideogram, Z-Image, SeedVR, FlashVSR, or crop outputs. Matching hashes across two different queues means the tensor is truly identical - bit for bit. Different hashes mean the pipeline changed even if the frames look the same to your eye. That distinction is the whole game when you're chasing "why did this generation come out identical to the last one?"

What it does

Feed it an IMAGE. It's an output node (OUTPUT_NODE = True), so its report appears in the UI text area. The optional label (default ideogram_image) just tags which probe this is, which matters when you've got four of them scattered through a graph.

Outputs: the image passes straight through untouched - this node never modifies anything - and report is the JSON string with the hash, dimensions, and other tensor metadata. Wire image onward to your next node and read report for debugging.

Why you'd bother

The author's framing is spot-on: in multi-queue storyboard pipelines, "same seed" bugs and "the prompt didn't change anything" bugs both masquerade as image problems. A hash probe splits prompt issues from pipeline issues in one glance. And because it's passive, you can leave it inline permanently - it costs almost nothing and you'll be glad it's there the day a workflow "stops working" after you rewired something.

Install

It's part of IAMCCS-nodes, like everything in this pack:

cd ComfyUI/custom_nodes
git clone https://github.com/IAMCCS/IAMCCS-nodes.git

or ComfyUI Manager → search IAMCCS. Restart after install. No dependencies beyond what ComfyUI already has.

The honest caveat

It's a debug tool, not a feature. If you don't need to prove two tensors are identical, you don't need it - it adds a report to your UI on every run and that's about it. But when you're debugging a storyboard pipeline where half the frames look suspiciously samey, it turns a two-hour visual hunt into a two-second hash comparison.