Image Parameter Bus

Every txt2img run starts with the same three numbers: the seed, the width, and the height. The seed goes to the KSampler, the width and height go to EmptyLatentImage, and normally that means three primitive nodes floating around the top of your graph - or worse, the values buried inside their destination nodes, which you'll hunt for later. The Image Parameter Bus puts all three in one node and hands them out as three plain integer outputs.

This is the node the pack's README singles out, and for a good reason: unlike the pure pass-through buses, this one genuinely earns its place as an input node. Its three inputs are widgets by default, so you set seed, width, and height once, in one place, and wire the outputs wherever they're needed. That's the "converted to widgets and used as the input node" trick the author mentions - instead of scattering primitives, you get a tidy little settings panel sitting at the head of your workflow.

The inputs and outputs

• seed (INT) - default 0, range 0 to 2⁶⁴−1. Feed it to your KSampler's seed input.
• width (INT) - default 1024, range 256–16384, snaps to multiples of 8.
• height (INT) - default 1024, same range and step.

The outputs are the same three values - seed, width, height - each a plain INT port. Typical wiring: width and height into EmptyLatentImage, seed into the KSampler. And because these inputs are widgets that can be converted to connections, you can also feed them from elsewhere - an API input, a resolution calculator - by right-clicking a widget and converting it to an input.

One honest caveat: the defaults (1024×1024, seed 0) are generic, not tuned for any model. If you're on SD1.5, 1024×1024 will blow up; set the size to something the checkpoint actually likes. The step of 8 keeps dimensions on the multiples most samplers expect.

Installing it

Part of the comfyui-bus-plugin pack, like every bus node. In ComfyUI Manager, search "comfyui-bus-plugin", Install, restart. Or from a terminal:

cd ComfyUI/custom_nodes
git clone https://github.com/rhdunn/comfyui-bus-plugin

then restart. No dependencies, no models, no config - it's a few hundred lines of pure Python.

Common issues

The usual stumble is treating it like a magic source that other nodes read automatically. It's not - you still wire the outputs to their destinations; the win is that all three values live in one node. Also, don't look for a "resolution" output here; this bus only knows the raw width and height, so if you want the latent's total pixel count or a ratio, compute that downstream. For a beginner, this is honestly the most useful node in the pack - grab it, set your size and seed, and stop fishing values out of buried widgets.