Reverse Image Batch

This one does exactly what the name says and nothing more: it takes a batch of images and reverses the order. Frame 0 becomes the last frame, the last becomes frame 0. If you were hoping for something clever, that's it - but it's one of those tiny utilities you end up wiring in constantly once you're doing video.

Where it earns its keep is animation. In ComfyUI a "batch of images" is how video frames travel through a graph, so reversing the batch reverses the clip. Play a pour backwards, run a walk cycle in reverse, or - the classic - build a boomerang by taking your frames, reversing a copy, and joining the two so the video plays forward then bounces back. That ping-pong loop is a staple, and this node is the piece that makes the second half.

How it works

There's genuinely no mechanism to explain. It reverses the list. No interpolation, no re-timing, no blending - the exact same frames come out, just in the opposite order. Because it's pure reordering, it's instant and it can't degrade your images.

It's a good example of what Kijai's KJNodes pack is: a grab-bag of small quality-of-life nodes, kept deliberately light, that exist because someone (often Kijai) needed the thing and figured everyone else would too. This is a two-line function wrapped in a node so you don't have to build it yourself.

The inputs and outputs that matter

• images (IMAGE) - the batch to flip. That's the only input.
• Output is IMAGE - the same batch, reversed. Wire it into a video combine node, a preview, or a join node for the boomerang trick.

That's the whole surface. Nothing to tune.

How to install it

ComfyUI Manager is the easy road: search KJNodes for ComfyUI, install, restart.

Manual install:

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

Restart ComfyUI and find it under KJNodes/image. No models, no heavy deps - the pack keeps requirements minimal on purpose.

Common issues & troubleshooting

Honestly, there's not much to break here. A couple of things worth knowing:

It reverses frame order, not the frames themselves. If you wanted each image mirrored left-right, that's a horizontal flip, a different operation entirely. This node touches order only.

Boomerangs will have a duplicate frame at the seam. If you join a batch with its own reverse, the last frame of the forward pass and the first frame of the reverse are the same image, so you get a one-frame stutter at the turnaround. Trim one frame off before joining if that pause bugs you - a GetImagesFromBatchIndexed or a slice upstream handles it.

A single image isn't a batch. Reversing a batch of one gives you the same image back, which is correct but probably not what you meant. Make sure the frames you want reversed actually arrive as one batch, not separate outputs.