Civitai Video Interpolation

Frame interpolation is the boring-important step nobody gets excited about: it invents the in-between frames so a 12 fps generation plays back at 24 or 48 without looking like a slideshow. This node does that for you on Civitai's servers, billed in Buzz, no model downloads, no GPU grunt. You wire in the VIDEO your generator produced, pick a factor, and get back a smoother clip.

It's a genuinely useful utility, and the reason you'd take the cloud route is pure math: interpolating video is one more heavy model on top of the generation itself, and if you're already paying Civitai to make the video, offloading the smoothing too keeps your local rig out of the loop entirely. It also pairs naturally with the pack's other video helpers - generate, then interpolate, then run the result through the Civitai Video Upscaler - as a three-node post pipeline that never touches your GPU.

How it works

Same skeleton as the rest of the pack. The node uploads your video, submits a videoInterpolation workflow to Civitai's orchestration API, long-polls until it's done, and hands the result back as a native ComfyUI VIDEO. The work - including the VFIMamba model that's the default - runs entirely on Civitai's fleet.

The inputs that matter

It's a small node, and that's the appeal.

• video (required) - the clip to smooth. Wire it from any node that outputs VIDEO, including the other Civitai generation nodes.
• interpolation_factor - 2 or 3, default 2. That's frames-out per frames-in: factor 2 doubles the frame count, factor 3 triples it. A 12 fps source at factor 2 gives you ~24 fps playback.
• model - a plain STRING, default VFIMamba. It maps to the VFI-Mamba family of mamba-based frame-interpolation models. Leave it alone unless you know the fleet accepts something else.

Outputs are the standard trio: video, workflow_id, and raw_json.

Install and auth

Part of the official civitai-comfy-nodes pack - install once, get all ~160 nodes. ComfyUI Manager → Custom Nodes Manager → search Civitai Comfy Nodes → Install → restart. Manual:

cd ComfyUI/custom_nodes
git clone https://github.com/civitai/civitai-comfy-nodes.git
pip install -r civitai-comfy-nodes/requirements.txt   # just requests

Auth: Civitai Auth node → CIVITAI_API_TOKEN env var → stored key/OAuth from the Civitai sidebar → browser login, in that order.

Where people get burned

Two honest caveats. First, interpolation can't fix a source that's already a mess - if the generator produced warped or flickering frames, smoothing them just makes the artifacts smoother. Second, it's a per-job cloud cost, and unlike local RIFE-style interpolation it never gets faster or free. Also keep an eye on the factor: going straight to 3 on low-fps generation can produce that uncanny "soap opera" look. Factor 2 is the sane default for a reason.