Preview (webm)

Scrubbing through a batch of frames one at a time tells you very little about how the animation actually reads - motion is the whole point, and a filmstrip view can't show it to you. Preview (webm) encodes your frame batch into a WebM clip on the spot and plays it back right in the node, so you can judge timing, jitter, and flow without exporting anything or leaving ComfyUI.

How it works

Feed it a batch of frames and a frame rate, and it encodes them into a WebM video and shows you the result inline. It's a preview-only node - nothing gets saved to disk, nothing passes downstream. Think of it as the video equivalent of Fast Image Preview elsewhere in this pack: fast feedback, not a deliverable.

The inputs and outputs that matter

• frames (IMAGE, required) - the batch to encode and play.
• fps (FLOAT, default 8, range 0.1–120) - playback frame rate. Set this to whatever your actual intended output rate is; previewing at the wrong fps will make perfectly good timing look sped up or sluggish and lead you to "fix" a problem that isn't there.

There are no outputs - this is a terminal node, same as this pack's other preview nodes. If you need the frames for anything else, branch the wire upstream of it.

How to install it

Via ComfyUI Manager: search "Link Comfy Nodes," install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/Mister-Link/link-comfy-nodes
pip install -r link-comfy-nodes/requirements.txt

Restart ComfyUI once done. Video encoding nodes are exactly where a skipped dependency install shows up first - if this one specifically fails while everything else in the pack works, that's the first thing to check.

Common issues & troubleshooting

Node imports fine but encoding fails at runtime. This is the classic sign of a missing or incomplete pip install -r link-comfy-nodes/requirements.txt - the pack's Python files loaded fine, but a video-encoding dependency needed only at runtime wasn't actually installed. Re-run the requirements install inside the same Python environment ComfyUI is using (easy to get wrong if you're on a venv or portable install) and restart.

Preview looks choppier or faster than your real export. Double-check fps actually matches your intended output rate - it's a separate, independent value from anything else in your graph, so if you generated frames meant for 24fps but left this at the default 8, the preview will look nothing like the real thing.

Large batches taking a while to encode. Video encoding is inherently heavier than a still-image preview. If you're iterating quickly on a big batch, preview a shorter clip or a downsampled subset first (pair it with Load Folder's select_every_nth, or trim your batch before this node) rather than re-encoding the full sequence on every change.