| # Advanced workflows |
|
|
| ## Extend an existing video |
|
|
| Use **MiniMax H3 Existing Video Context** when scene 1 must continue a decoded |
| video rather than start from an empty timeline. The complete experimental model |
| is [Extend Existing Video Model Workflow - MiniMax H3](<../example_workflows/Archive/Extend Existing Video Model Workflow - MiniMax H3.json>). |
|
|
| ```text |
| Plan ────────────────────────────────┐ |
| Core Load Video (VIDEO) ─────────────┼→ Existing Video Context → Loop Start |
| Other loader IMAGE + AUDIO + FPS ────┘ |
| H3 audio VAE ─────────────────────────────────────────────→ Loop Context |
| ``` |
|
|
| Use exactly one video route: |
|
|
| - `source_video` accepts native ComfyUI VIDEO, including embedded audio and |
| exact FPS. An explicit audio input overrides embedded audio. |
| - `source_frames` accepts IMAGE from VHS or another decoder. Connect optional |
| AUDIO and set the real decoded `source_fps`. |
|
|
| The adapter normalizes frames to the Plan canvas and H3's 24 fps, uses the last |
| `context_length` frames as scene 1's predecessor, and can persist the normalized |
| source as a prelude. In head mode: |
|
|
| ```text |
| scene 1 delivered frames = raw frames - imported context frames |
| ``` |
|
|
| Connect the audio VAE to Loop Context for imported-audio timeline guidance in |
| `generated_audio` or `source_plus_timeline`. Visual continuation still works |
| without imported audio. |
|
|
| With `prepend_original=true`, Assemble places the normalized original before |
| generated scenes, including partial output. Arbitrary source codecs and frame |
| rates cannot be stream-concatenated safely, so the prelude is encoded once at |
| the Plan's `segment_crf`; generated H.264 segments remain stream-copied. |
|
|
| The imported tail is fingerprinted. Reconnect the same Plan and source when |
| resuming; a changed source correctly invalidates dependent checkpoints. |
|
|
| Recommended first settings: |
|
|
| ```text |
| Chain Policy Guide |
| encode_mode video |
| anchor_mode head |
| Loop Trim match_tail true |
| Spectrum off |
| ``` |
|
|
| Chain Policy derives both visual and generated-audio overlap as 22 frames for |
| Guide. Use the Legacy 0.4 Policy Adapter only when this imported-context workflow |
| deliberately needs different visual and audio overlap lengths. |
|
|
| ## Long visual context |
|
|
| `56` is a valid advanced context length. It carries 2.33 seconds of motion in |
| 17 video latent steps, but head mode regenerates and removes all 56 frames from |
| every continuation. Start with `22`; use `56` when a long clip's camera move or |
| performance genuinely needs more history. |
|
|
| ## Non-linear visual context |
|
|
| Scenes 2 and later normally take visual context from the immediately previous |
| timeline scene. **Visual context source** in Plan or Plan Studio can instead |
| select any earlier saved scene by stable scene ID: |
|
|
| ```json |
| { |
| "id": "scene_5", |
| "visual_context_source": "scene_3", |
| "context_length": 39, |
| "video_blend_frames": 0 |
| } |
| ``` |
|
|
| This changes only the picture-side continuation edge. In this example scene 5 |
| uses scene 3's retained RGB/video latent, while Generated continuity still |
| uses scene 4's audio latent. The timeline, branch ancestry, soundtrack clock, |
| and final ordering remain 1 → 2 → 3 → 4 → 5. With head anchoring, the repeated |
| scene-3 prefix is removed by Loop Trim, so `video_blend_frames: 0` delivers a |
| hard cut from scene 4 to the newly generated part of scene 5. |
|
|
| Non-linear visual context requires a zero assembly blend because the visible |
| incoming timeline boundary is still scene 4 → scene 5. Checkpoint preflight |
| verifies both consumed dependencies independently: the selected visual scene |
| and, when enabled, the immediate generated-audio predecessor. Other earlier |
| scenes remain assembly-only and do not become false resume blockers. |
|
|
| ### Selecting a source segment instead of its tail |
|
|
| Plan Studio's **Context** tab previews the complete delivered video for every |
| visual context block. The highlighted zone is the actual fixed-size context |
| window: its width is proportional to the configured frame span. Drag that |
| zone across the movie, place it near the player's current frame, or play only |
| the selected window. The position snaps to H3's native 17-frame / five-latent- |
| step temporal lattice. **Tail (default)**, or **Latest aligned (default)** |
| when that block's phase cannot end on the physical tail, removes the override. |
|
|
| The stored values are zero-based frame indexes within the source scene's |
| delivered video (after that source's own incoming overlap was trimmed): |
|
|
| ```json |
| { |
| "id": "scene_5", |
| "context_length": 22, |
| "visual_context_source": "scene_3", |
| "visual_context_start_frame": 119, |
| "video_blend_frames": 0 |
| } |
| ``` |
|
|
| For an untrimmed source this selects delivered frames 119 through 140 from |
| scene 3. Valid numeric starts depend on the source's own trimmed incoming |
| prefix, so use Plan Studio instead of hand-authoring an arbitrary frame. The |
| backend converts both ends to native latent-step boundaries and slices the |
| saved video latent directly. It never replaces that crop with an RGB VAE |
| re-encode; RGB Guide/mask consumers use retained frames or a decode-only |
| mirror. Generated-audio continuity remains the immediate previous scene's |
| tail. |
|
|
| ## Composed visual context |
|
|
| A continuation can use any ordered number of saved picture histories back to |
| back. In Plan Studio's **Context → Picture** tab, select the total, the number |
| of blocks, and the cumulative H3-native divisions. Every block then exposes |
| its own earlier-scene source and exact latent-window selector. The last block |
| sits immediately before the new generation: |
|
|
| ```json |
| { |
| "id": "scene_5", |
| "context_length": 39, |
| "visual_context_blocks": [ |
| {"source": "scene_3", "frames": 5}, |
| {"source": "scene_4", "frames": 12, "start_frame": 0}, |
| {"source": "scene_3", "frames": 22} |
| ], |
| "video_blend_frames": 0 |
| } |
| ``` |
|
|
| This example constructs one 39-frame visual prefix: |
|
|
| ```text |
| scene 3 block: 5 RGB frames / 2 video-latent steps |
| scene 4 block: 12 RGB frames / 3 video-latent steps |
| scene 3 block: 22 RGB frames / 7 video-latent steps |
| result: 39 RGB frames / 12 video-latent steps |
| ``` |
|
|
| The division selectors expose every valid ordered repartition without building |
| an enormous combination menu. For example, three blocks within `39` include |
| `5+12+22`, `5+17+17`, `5+29+5`, `17+5+17`, `17+17+5`, and `22+12+5`. |
| Changing the count starts from a balanced valid repartition; moving each |
| division explores all other native layouts. |
|
|
| The blocks are concatenated in their authored order; they are not blended or |
| interpolated. Both `22+17` and `17+22` now select source windows on the target |
| block's matching temporal phase and concatenate the saved latent crops |
| directly. For an inverse layout, the first block's latest aligned crop can end |
| before its source movie's physical tail; Plan Studio shows that position. |
| Every source may be any earlier scene on the active branch. Sources do not |
| need to be chronologically ordered and the same source can appear more than |
| once with independent windows. The composed prefix remains one context, so |
| its normal head trim or AV mask uses the selected total exactly once. |
|
|
| Composition changes only picture context. Generated audio remains one complete |
| latent tail from the immediately previous timeline scene, so there is no audio |
| splice at the internal visual seam and a scene's independent audio-context |
| override still works. Final assembly still follows normal scene order and must |
| use `video_blend_frames: 0` at this boundary. Checkpoint preflight verifies |
| every selected visual revision plus the immediate audio predecessor when that |
| audio continuity is active. |
|
|
| Each `visual_context_blocks` item may omit `start_frame` to use its latest |
| phase-aligned native crop. The released `visual_context_source` and |
| `visual_context_lead_*` one/two-block fields remain accepted for existing |
| Plans and checkpoints, but the new builder writes only the ordered list. |
|
|
| ## Independent audio context |
|
|
| Plan Studio's **Context** planner keeps Audio locked by default. This preserves |
| the established behavior: picture may use one or more selected windows, while |
| generated audio remains one continuous tail from the immediately previous |
| timeline scene. Existing plans therefore do not change. |
|
|
| Choose **Unlock audio context** to reveal the Audio tab for that scene. It can |
| select one earlier saved scene and an exact audio-latent range, or prepend a |
| second independently positioned range. The two blocks are sequential context |
| excerpts—not a decoded waveform mix—so they can, for example, expose voice |
| regions from two characters before the new scene is generated: |
|
|
| ```json |
| { |
| "id": "scene_5", |
| "audio_context_unlocked": true, |
| "audio_context_source": "scene_3", |
| "audio_context_start_frame": 0, |
| "audio_context_lead_source": "scene_4", |
| "audio_context_lead_frames": 5, |
| "audio_context_lead_start_frame": 12 |
| } |
| ``` |
|
|
| The lead block is first and `audio_context_source` is nearest generation. Both |
| sources may point to the same scene to select two different moments. Positions |
| are delivered-frame indexes and snap to crops whose duration is exact on H3's |
| 40 Hz audio-latent clock; the saved audio tensors are sliced directly without |
| decode/re-encode. AV prefix implementations still use the picture context |
| duration as their shared target span. Locking Audio again removes these custom |
| fields and restores immediate-predecessor continuity. |
|
|
| ## Last-frame destinations |
|
|
| When stock H3 Image to Video supplies `last_frame`, Motion Context preserves |
| that target on continuation scenes. The carried repeated head replaces a |
| conflicting `first_frame` anchor because both cannot own the same opening |
| coordinates. |
|
|
| Place official **MiniMax H3 Add Guide** nodes after Loop Context for additional |
| scene-local image, video, or audio anchors. |
|
|
| ## Re-film a synchronized performance |
|
|
| The [three-angle guitar workflow](<../example_workflows/Archive/Three-Angle Guitar Ref2VA - EXPERIMENTAL - MiniMax H3.json>) |
| uses **Reference Video Prep** to convert native VIDEO or decoded IMAGE/AUDIO |
| into exact 24 fps Ref2VA input. Its soundtrack is copied without padding or |
| time-stretching, allowing one performance to be generated from multiple camera |
| angles in one pass. |
|
|
| Reference Video Prep rejects sources shorter than the requested H3-valid length |
| instead of silently padding or stretching them. |
|
|
| ## External stitchers |
|
|
| Loop Trim's `images_with_overlap` output exposes part of the repeated visual |
| context while leaving its normal images and audio fully trimmed. Connect |
| **Current Shot → state** to **Loop Trim → state**. Loop Trim then resolves each |
| incoming scene's optional `video_blend_frames` override, or the Plan default |
| when the scene value is blank. Scene N controls the N−1→N boundary. Keep it at |
| `0` for a hard boundary. The old Plan/default and Current Shot/resolved integer |
| outputs remain compatibility sockets only; do not wire either one in a 0.5 |
| workflow. |
|
|
