LTX2 video generation

LTX2 is Lightricks' open video-generation model family. The orchestrator exposes both LTX2 and the newer LTX2.3 through the videoGen step, running on Civitai's ComfyUI workers. This recipe covers both versions end-to-end.

Versions at a glance

engine	Models	Operations	Notes
ltx2.3	22b-dev, 22b-distilled	createVideo, firstLastFrameToVideo, editVideo, extendVideo, videoToVideo, audioToVideo	Current release. Adds style transfer (videoToVideo) and audio-driven talking-head generation (audioToVideo).
ltx2	19b-dev, 19b-distilled	createVideo, firstLastFrameToVideo, editVideo, extendVideo	Previous release. Still supported.

Default choice for new integrations: engine: "ltx2.3", model: "22b-distilled" for speed, "22b-dev" for maximum quality.

The request shape

Every LTX2 request is a single videoGen step on SubmitWorkflow. Three keys select which LTX2 variant runs:

{
  "$type": "videoGen",
  "input": {
    "engine":    "ltx2.3",       // ltx2 | ltx2.3
    "operation": "createVideo",  // see table above
    "model":     "22b-distilled" // version-specific
  }
}

There's no provider discriminator — LTX2 currently only runs on Comfy. Each combination dispatches to its typed input schema (ComfyLtx23CreateVideoInput, ComfyLtx2EditVideoInput, …) so fields invalid for that combination get rejected with a 400.

Source-media inputs

editVideo, extendVideo, videoToVideo, and audioToVideo accept sourceVideo / sourceAudio as either:

• a Civitai AIR URN (urn:air:…), or
• a civitai-hosted URL (image.civitai.com, orchestrator blob URLs, civitai-managed R2 / B2 / Spaces).

Arbitrary third-party URLs (e.g. raw.githubusercontent.com, cdn.jsdelivr.net) are not fetched — requests that pass one are rejected with a 400. Upload the media to Civitai first and pass the resulting URL. images, firstFrame, lastFrame, and referenceImage go through a separate image pipeline and do accept external URLs — only video/audio inputs have this restriction today.

Operations

All examples target production and use <your-token> in place of your Bearer token. LTX2 jobs typically exceed the 100-second request timeout — submit with wait=0 and handle completion via webhooks or polling.

createVideo

Single operation covers both text-to-video and image-to-video — add images to turn any text-to-video request into image-to-video.

POST https://orchestration.civitai.com/v2/consumer/workflows?whatif=false&wait=0
Authorization: Bearer <your-token>
Content-Type: application/json

{
  "steps": [{
    "$type": "videoGen",
    "input": {
      "engine": "ltx2.3",
      "operation": "createVideo",
      "model": "22b-distilled",
      "prompt": "A beautiful sunset over the ocean with waves crashing",
      "duration": 5,
      "width": 1280,
      "height": 720,
      "fps": 24,
      "generateAudio": false,
      "guidanceScale": 4,
      "numInferenceSteps": 20
    }
  }]
}

POST/v2/consumer/workflows

Set your Civitai API token via the Token button in the navbar to enable Try It.

Request body — edit to customize (e.g. swap the image URL or prompt)

{ "steps": [ { "$type": "videoGen", "input": { "engine": "ltx2.3", "operation": "createVideo", "model": "22b-distilled", "prompt": "A beautiful sunset over the ocean with waves crashing", "duration": 5, "width": 1280, "height": 720, "fps": 24, "generateAudio": false, "guidanceScale": 4, "numInferenceSteps": 20 } } ] }

Valid JSON

Image-to-video: pass one or more images via images.

{
  "engine": "ltx2.3",
  "operation": "createVideo",
  "model": "22b-dev",
  "prompt": "The cat starts walking and exploring",
  "images": [
    "https://image.civitai.com/.../42750475.jpeg"
  ],
  "duration": 5,
  "width": 1280,
  "height": 720,
  "fps": 24
}

POST/v2/consumer/workflows

Set your Civitai API token via the Token button in the navbar to enable Try It.

Request body — edit to customize (e.g. swap the image URL or prompt)

{ "steps": [ { "$type": "videoGen", "input": { "engine": "ltx2.3", "operation": "createVideo", "model": "22b-dev", "prompt": "The cat starts walking and exploring", "images": [ "https://image.civitai.com/xG1nkqKTMzGDvpLrqFT7WA/c7281429-7dc8-4256-9907-2e2c55137f40/original=true,quality=90,optimized=true/42750475.jpeg" ], "duration": 5, "width": 1280, "height": 720, "fps": 24 } } ] }

Valid JSON

firstLastFrameToVideo

Interpolate between two keyframes (or extend from a single first frame).

{
  "engine": "ltx2.3",
  "operation": "firstLastFrameToVideo",
  "model": "22b-dev",
  "prompt": "smooth transition from morning to night",
  "firstFrame": "https://.../start.jpeg",
  "lastFrame":  "https://.../end.jpeg",
  "frameGuideStrength": 0.8,
  "duration": 5,
  "width": 1280,
  "height": 720,
  "fps": 24
}

Omit lastFrame to seed the motion from just the first frame.

POST/v2/consumer/workflows

Set your Civitai API token via the Token button in the navbar to enable Try It.

Request body — edit to customize (e.g. swap the image URL or prompt)

{ "steps": [ { "$type": "videoGen", "input": { "engine": "ltx2.3", "operation": "firstLastFrameToVideo", "model": "22b-dev", "prompt": "smooth transition from morning to night", "firstFrame": "https://image.civitai.com/xG1nkqKTMzGDvpLrqFT7WA/c7281429-7dc8-4256-9907-2e2c55137f40/original=true,quality=90,optimized=true/42750475.jpeg", "lastFrame": "https://image.civitai.com/xG1nkqKTMzGDvpLrqFT7WA/e4a8f395-8166-44a8-82b1-bb0901c10aa3/original=true,quality=90,optimized=true/19325406.jpeg", "frameGuideStrength": 0.8, "duration": 5, "width": 1280, "height": 720, "fps": 24 } } ] }

Valid JSON

editVideo

Input video + prompt → transformed video. Uses Canny edge-maps for structural preservation.

{
  "engine": "ltx2.3",
  "operation": "editVideo",
  "model": "22b-dev",
  "prompt": "Transform the scene into a cyberpunk aesthetic with neon lighting",
  "sourceVideo": "https://.../input.mp4",
  "cannyLowThreshold": 0.4,
  "cannyHighThreshold": 0.8,
  "guideStrength": 0.7
}

POST/v2/consumer/workflows

Set your Civitai API token via the Token button in the navbar to enable Try It.

Request body — edit to customize (e.g. swap the image URL or prompt)

{ "steps": [ { "$type": "videoGen", "input": { "engine": "ltx2.3", "operation": "editVideo", "model": "22b-dev", "prompt": "Transform the scene into a cyberpunk aesthetic with neon lighting", "sourceVideo": "https://image.civitai.com/xG1nkqKTMzGDvpLrqFT7WA/a35b4935-3e7a-46a6-b2f7-efbe220b7eab/transcode=true,original=true,quality=90,optimized=true/70182582.webm", "cannyLowThreshold": 100, "cannyHighThreshold": 200, "guideStrength": 0.7 } } ] }

Valid JSON

extendVideo

Continue an existing clip for numFrames more frames.

{
  "engine": "ltx2.3",
  "operation": "extendVideo",
  "model": "22b-dev",
  "prompt": "The scene continues with gentle camera push-in",
  "sourceVideo": "https://.../clip.mp4",
  "numFrames": 48,
  "fps": 24
}

POST/v2/consumer/workflows

Set your Civitai API token via the Token button in the navbar to enable Try It.

Request body — edit to customize (e.g. swap the image URL or prompt)

{ "steps": [ { "$type": "videoGen", "input": { "engine": "ltx2.3", "operation": "extendVideo", "model": "22b-dev", "prompt": "The scene continues with gentle camera push-in", "sourceVideo": "https://image.civitai.com/xG1nkqKTMzGDvpLrqFT7WA/a35b4935-3e7a-46a6-b2f7-efbe220b7eab/transcode=true,original=true,quality=90,optimized=true/70182582.webm", "numFrames": 48, "fps": 24 } } ] }

Valid JSON

videoToVideo (LTX2.3 only)

Style-transfer an entire video.

{
  "engine": "ltx2.3",
  "operation": "videoToVideo",
  "model": "22b-dev",
  "prompt": "Rendered in the style of a watercolor painting",
  "sourceVideo": "https://.../clip.mp4"
}

POST/v2/consumer/workflows

Set your Civitai API token via the Token button in the navbar to enable Try It.

Request body — edit to customize (e.g. swap the image URL or prompt)

{ "steps": [ { "$type": "videoGen", "input": { "engine": "ltx2.3", "operation": "videoToVideo", "model": "22b-dev", "prompt": "Rendered in the style of a watercolor painting", "sourceVideo": "https://image.civitai.com/xG1nkqKTMzGDvpLrqFT7WA/a35b4935-3e7a-46a6-b2f7-efbe220b7eab/transcode=true,original=true,quality=90,optimized=true/70182582.webm" } } ] }

Valid JSON

audioToVideo (LTX2.3 only)

Audio-driven generation. With just sourceAudio, produces a matching visual scene; add referenceImage for talking-head / lip-sync output.

{
  "engine": "ltx2.3",
  "operation": "audioToVideo",
  "model": "22b-dev",
  "prompt": "A person speaks directly to camera with natural lip movements",
  "negativePrompt": "frozen lips, off-sync lips, blurry",
  "sourceAudio": "https://.../voiceover.mp3",
  "referenceImage": "https://.../portrait.jpeg",
  "audioToVideoAttentionScale": 2.0,
  "imageGuideStrength": 0.7,
  "duration": 5,
  "width": 1280,
  "height": 720,
  "fps": 24
}

POST/v2/consumer/workflows

Set your Civitai API token via the Token button in the navbar to enable Try It.

Request body — edit to customize (e.g. swap the image URL or prompt)

{ "steps": [ { "$type": "videoGen", "input": { "engine": "ltx2.3", "operation": "audioToVideo", "model": "22b-dev", "prompt": "A person speaks directly to camera with natural lip movements", "negativePrompt": "frozen lips, off-sync lips, blurry", "sourceAudio": "<replace with a civitai-hosted audio URL>", "referenceImage": "https://image.civitai.com/xG1nkqKTMzGDvpLrqFT7WA/c7281429-7dc8-4256-9907-2e2c55137f40/original=true,quality=90,optimized=true/42750475.jpeg", "audioToVideoAttentionScale": 2, "imageGuideStrength": 0.7, "duration": 5, "width": 1280, "height": 720, "fps": 24 } } ] }

Valid JSON

Common parameters

Shared across most (engine, operation) combinations. The per-variant schema in the API reference is authoritative.

Field	Typical values	Notes
model	22b-dev / 22b-distilled (2.3); 19b-dev / 19b-distilled (2.0)	-distilled is faster with slightly lower fidelity; -dev is maximum quality.
width / height	1280×720, 720×1280, 1024×1024	Vertical for phones: swap to 720×1280.
duration	3 or 20 seconds	Only these two values are accepted; no intermediate durations.
fps	24, 30	Frame rate of the generated clip.
guidanceScale	3–7	Prompt adherence. Higher = closer to prompt but less creative.
numInferenceSteps	8–50	20–40 is the practical quality sweet spot. More steps = higher quality, longer runtime.
generateAudio	true / false	Emit a soundtrack alongside the video.
negativePrompt	string	What you don't want.
seed	integer	Reproducibility.
loras	object	Attach community LoRAs to bias style or subject. Format: { "urn:air:lora:civitai:<modelId>@<versionId>": 0.8 } — a dictionary keyed by AIR URN with the strength as the value.

Choosing a model

Need	Pick
Fastest turnaround, batch generation	22b-distilled (or 19b-distilled)
Highest fidelity, final-quality renders	22b-dev
Parity with an older pipeline	19b-dev / 19b-distilled

Reading the result

Same as any videoGen step — a single video blob per clip:

{
  "status": "succeeded",
  "steps": [{
    "name": "0",
    "$type": "videoGen",
    "status": "succeeded",
    "output": {
      "video": { "id": "blob_...", "url": "https://.../signed.mp4" }
    }
  }]
}

Blob URLs are signed and expire — refetch the workflow or call GetBlob for a fresh URL.

Long-running jobs

LTX2.3 22b-dev at 1280×720 / 5 s typically runs 2–5 minutes; editVideo and audioToVideo can go longer. All of these exceed the 100-second request timeout, so prefer wait=0 and:

• Webhooks (recommended): register a callback with type: ["workflow:succeeded", "workflow:failed"] — see Results & webhooks
• Polling: GET /v2/consumer/workflows/{workflowId} on a 10 s → 30 s → 60 s cadence

Troubleshooting

Symptom	Likely cause	Fix
400 with unknown field	Field isn't valid for this (engine, operation) combo	Check the specific ComfyLtx<Ver><Op>Input schema via SubmitWorkflow.
400 "'sourceVideo' / 'sourceAudio' must be a Civitai AIR URN…"	Passed an external URL to sourceVideo or sourceAudio	Re-upload the media to Civitai and use the civitai-hosted URL, or pass a urn:air:… URN. See Source-media inputs.
Step failed, reason = "no_provider_available"	No Comfy worker has the requested model warm	Retry shortly; or try the other model (-dev ↔ -distilled).
Audio-to-video lip-sync poor	Attention scale too low, or audio clipping	Raise audioToVideoAttentionScale (e.g. 2.0 → 3.0); re-encode source audio at constant bitrate.
Edit-video loses structure	Canny guide too weak	Raise guideStrength (0.7 → 0.85) or widen the Canny thresholds.

Cost

Billed in Buzz on the workflow's transactions. Use whatif=true for an exact preview; see Payments (Buzz) for currency selection.

All LTX2 / LTX2.3 variants use the same formula — pixel volume × a per-pixel rate × a steps multiplier:

numFrames          = duration × fps
pixelVolumeInMP    = (width × height × numFrames) / 1 000 000
stepsMultiplier    = steps / 20

total = ceil(pixelVolumeInMP × 0.0008 × 1000 × 1.5 × stepsMultiplier)

Shape	Buzz
720p (1280×720), 5 s @ 24 fps, steps: 20	~133
720p, 5 s @ 24 fps, steps: 40	~266
720p, 10 s @ 24 fps, steps: 20	~266
1080p (1920×1080), 5 s @ 24 fps, steps: 20	~299

extendVideo and editVideo scale by their total output frame count the same way. LTX2 is the cheapest video-gen path Civitai exposes — expect roughly linear cost growth with pixels × frames × steps.

Related

• SubmitWorkflow — operation used by every example here
• GetWorkflow — for polling
• Results & webhooks — production-ready result handling
• WAN video generation — comparable recipe for the WAN model family
• Full parameter catalog: the ComfyLtx23<Operation>Input and ComfyLtx2<Operation>Input schemas in the API reference
• videoGen endpoint OpenAPI spec — standalone OpenAPI 3.1 YAML covering the full videoGen surface (WAN, LTX2, Flux, etc.); import into Postman / OpenAPI Generator