Pika H3 Flex turns two images into video with stereo audio.

Who it's for: creators who want this pipeline in ComfyUI without assembling nodes from scratch. Not for: one-click results with zero tuning - you still choose inputs, prompts, and settings.

Open preloaded workflow on RunComfy

Open preloaded workflow on RunComfy (browser)

Why RunComfy first
- Fewer missing-node surprises - run the graph in a managed environment before you mirror it locally.
- Quick GPU tryout - useful if your local VRAM or install time is the bottleneck.
- Matches the published JSON - the zip follows the same runnable workflow you can open on RunComfy.

When downloading for local ComfyUI makes sense - you want full control over models on disk, batch scripting, or offline runs.

How to use (local ComfyUI)
1. Load inputs (images/video/audio) in the marked loader nodes.
2. Set prompts, resolution, and seeds; start with a short test run.
3. Export from the Save / Write nodes shown in the graph.

Expectations - First run may pull large weights; cloud runs may require a free RunComfy account.

Overview

Turn two reference images into video with Pika H3 Flex. Guide your scene with a prompt. Get short clips with stereo audio. Use eight-step Pika Turbo generation. Compare Pika and MiniMax outputs using the same subjects, prompt, and seed.

Important nodes:

Key nodes in Comfyui Pika H3 Flex ComfyUI Workflow

MiniMaxH3ReferenceToVideo (#6617)

Centralizes Ref2VA by combining your two references, prompt, and target dimensions into a single positive conditioning and an initial latent. Adjust only the essentials here: scene prompt, choice and order of reference images, and the duration/size that fit your shot. Keep the same settings when comparing branches so differences reflect the LoRA, not the conditioning. The node is designed to drive both video and stereo audio that get decoded downstream using the MiniMax H3 VAEs described in their model card.

Resolution Selector (Size) (#6345)

Picks aspect ratio and megapixels, then returns width and height aligned to multiples of 32 for efficient decoding. Use it as the one place to size both branches, which minimizes resample artifacts and keeps per‑frame detail consistent. Increasing resolution raises compute cost and reduces step‑time headroom, so scale gradually when fine‑tuning look and motion.

StringConcatenate (#6346)

Applies a compact realism primer before your prompt. If you prefer a different tone or stylization, replace or remove the primer to let your own wording dominate. Keeping this node consistent across runs helps preserve A/B integrity when testing nuanced phrasing changes.

BasicScheduler (#6742, #6767)

Provides an eight‑step schedule optimized for quick, stable results in this Ref2VA setup. Fewer steps trade detail for speed, while more steps add refinement at the cost of time. For clean A/Bs across branches, keep steps identical.

VHS_VideoCombine (#6758, #6776)

Muxes decoded frames and stereo audio into final MP4 files. Control format and frame rate here, and keep both branches synchronized. If you change duration upstream, confirm the writer’s settings so the audio and video remain aligned.

Notes

Pika H3 Flex ComfyUI | 8-Step Ref2Video + Stereo Audio - see RunComfy page for the latest node requirements.