⭐ Star Grid Image Batcher

ComfyUI has a quirk that trips up every beginner sooner or later: a node that outputs a single IMAGE and a node that outputs a batch of IMAGEs look identical on the wire, but the grid and collage nodes you want to use downstream need a batch. Star Grid Image Batcher is the utility that gathers up to 16 loose images and stacks them into one tensor so the ⭐ Star Grid Composer (its sibling in the StarNodes pack) can lay them out.

What it actually does

There are two ways in, and you'll probably use both. The image_batch input accepts an existing batch and passes it through - so if a Load Images node already gave you five frames, they carry over. Then the numbered inputs, image 1 through image 16, let you wire individual outputs (say, a before image, an after image, and a few variations) and they all get concatenated into the single Grid Image Batch output. The node just concatenates along the batch axis; it does not resize, normalize, or otherwise touch your pixels, so whatever dimensions your images have, they keep. That's a feature here - the Grid Composer handles aspect ratios on its end.

It's deliberately tiny, and that's fine. You reach for it in exactly one situation: you have a handful of images scattered across different nodes and you want them treated as one batch. The most common real-world setup is four A/B/C/D candidates from a sampler comparison, or a before/after pair from an upscale workflow, wired into the image 1 / image 2 inputs and then into Grid Composer for a labeled sheet.

Inputs and output

• image_batch - an existing batch you want to keep. Optional.
• image 1 … image 16 - individual images, wired one per output you want in the grid. Optional; you only need what you're using.
• Grid Image Batch (output) - the combined IMAGE batch. Connect it to Grid Composer's Grid Image Batch input, or straight into a Save node if you just wanted frames merged.

Note there's no visible "batch size" counter - the inputs are dynamically added by the frontend, so plug in as many as you need up to the cap.

Installing

Same one-liner as the rest of the pack - install Starnodes from ComfyUI Manager, or:

cd ComfyUI/custom_nodes
git clone https://github.com/Starnodes2024/ComfyUI_StarNodes
cd ComfyUI_StarNodes
pip install -r requirements.txt

Restart, then search star on the canvas (⭐StarNodes category). No models, no weights, no heavy dependencies - this is a pure tensor utility.

Common issues

If your grid comes out with empty cells, the culprit is almost always a missing image N input, not this node - the Grid Composer only fills cells up to cols * rows, and gaps look odd. If you connect a batch and individual images, they're appended in order (batch first, then image 1, image 2, …), so keep that ordering in mind when you're assigning captions downstream. And if an input shows as disconnected, double-check the output you meant is actually IMAGE type - a LATENT won't plug in.