Generate Veo3.1 Video

Here's the reason people pay for this one: Veo generates audio in the same pass as the video - synchronized sound effects and dialogue, not a separate foley step. The KB is unambiguous that this is a genuine capability gap in open weights, with LTX-2.3 the only local model attempting native audio-plus-video and still behind. That's the argument for a closed API node, and it's the one argument that holds.

What it is

KIE's Veo 3.1 generation endpoint as a ComfyUI node - prompt, images and controls in, VIDEO out. It's the pack's usual trick applied to Google's video model: documented request fields become widgets, URL fields become native sockets, connected media gets uploaded to KIE for you.

Two context notes that matter. Cost and censorship are both on you: this routes through a reseller, which is why people choose it (community price comparisons against Comfy's first-party API nodes have shown meaningful savings on Google models), and Google's generation stack is aggressively filtered, including tightening around famous IP and celebrity prompts. Expect refusals to be a policy answer, not a bug. The catalogue is live: KIE's Veo model IDs are publicly known to be documented with some stale identifiers embedded in their own pages, and the pack repairs for that - another reason to stay current.

Inputs

prompt (required) - the shot. Detailed, specific, with action and camera language. For image-to-video, describe how the frame should come alive.

generation_type - the mode switch, and the one to set deliberately. TEXT_2_VIDEO for prompt-only work; FIRST_AND_LAST_FRAMES_2_VIDEO for image-driven work, where one image is a start frame and two images are first and last; REFERENCE_2_VIDEO for reference-driven generation. Docs note the reference mode currently only supports an 8-second duration.

image_urls - a native IMAGE socket for the frames or references above.

duration - a string, default 8. Options are 4, 6, 8. Reference mode is 8 only, which is the constraint people hit.

resolution - 720p, 1080p, 4k.

aspect_ratio - 16:9, 9:16, or Auto. Auto centre-crops based on whether your uploaded image is closer to 16:9 or 9:16, which is a sensible default for image-driven runs.

enable_translation - true by default; prompts are translated to English before generation. Turn it off if your prompt is already English and you want exactly your wording to be what's sent.

watermark - text drawn onto the video if you fill it in. Defaults to MyBrand. Empty means no watermark.

enable_fallback - present but documented as deprecated. Leave it off.

timeout_seconds - 1200 default, 30–7200. callback_url - leave empty for normal ComfyUI use.

Outputs

video - a ComfyUI VIDEO object; Save Video or a preview node takes it directly. url - the primary hosted result. all_urls_json - every URL reported, which you want on a Veo job because the response can include still frames alongside the video. task_id - the job handle, and the thing you feed to the Get 1080P Video or Get 4K Video cards if you want a higher-resolution render of the same task. raw_json - the full response. credits_consumed and credits_left - floats, plus the on-node credits receipt.

Install

ComfyUI Manager (search the pack title), or:

cd ComfyUI/custom_nodes
git clone https://github.com/felipederosilva/ComfyUI-KIE-Nodes-Next
pip install -r ComfyUI-KIE-Nodes-Next/requirements.txt

Restart. Requirements: requests, Pillow, numpy, PyYAML. No local models, no VRAM, no rendering on your machine - every frame is generated remotely and billed.

Key: Settings → KIE.ai Nodes Next → Connection → Paste / replace KIE.ai API key; validated against KIE before saving, masked fingerprint afterwards. Headless: KIE_API_KEY, which outranks the saved key.

Gotchas

Duration and resolution interact. Reference mode is 8 seconds; going long or specific about length will trip either the mode or the resolution rules. Check the mode before you blame the model.

A refusal is a policy answer. Read raw_json; the text will usually say so.

Veo cards move. The pack generates nodes from KIE's documentation index at startup and re-checks roughly daily, and Veo identifiers have needed repair before. If a run fails oddly, update the pack and restart once before rebuilding anything.