GET

/v1/schemas/fal/video/fal-ai/ltx-2.3-quality/reference-video-to-video/lora

kind inputactivity videohash b4fa57c6…extracted Jul 6, 2026version currentsource upstream spec ↗
fieldrecorded source
schemaSource linked above.
Source trace
07c6405caf9a787a4e5bdda67fd5b03f5195800da55f9523dfa0c917d5f8f781
{
  "fetchedAt": 1783331098,
  "extractorVersion": "1",
  "verifiedAt": null
}

Request body

24 properties · 3 required · 2 $defs
propertytypedescriptionconstraints
prompt*stringThe prompt to guide generation.
video_url*stringThe URL of the reference video that supplies motion/structure.
loras*LoRAInput[]Up to 3 LoRAs to apply on top of LTX-2.3. Each path is downloaded through the registry SSRF-safe downloader before it is loaded. Max size: 3 GB per LoRA.items ≤ 3
num_framesintegerThe number of output frames to generate. This IC-LoRA endpoint caps the resolution x frames volume for stability (~150 frames at 720p-class; more at smaller sizes). A request above the budget returns a 422 — reduce num_frames or use a smaller resolution.9 ≤ n ≤ 481 · default: 121
guidance_scalenumberClassifier-free guidance scale. The default is tuned for fast, high-quality generation.1 ≤ n ≤ 20 · default: 1
frames_per_secondnumberFrames per second of the generated video.1 ≤ n ≤ 60 · default: 24
preserve_original_videobooleanTrue video-to-video: the base video_url is used as the generation's starting point, while control_video_url still drives the structure. The amount of the original preserved is controlled by `strength` (denoise): lower `strength` keeps more of the original vide…default: false
enable_prompt_expansionbooleanWhether to enable prompt expansion.default: true
enable_safety_checkerbooleanWhether to enable the safety checker.default: true
sync_modebooleanIf True, the media is returned as a data URI inline in the response. Useful for short-lived requests and tests.default: false
num_inference_stepsintegerNumber of inference steps. Defaults to 15 and can be increased up to 30.8 ≤ n ≤ 30 · default: 15
seedintegerRandom seed for reproducibility. If None, a random seed is chosen.nullable
strengthnumberSampler denoise strength for reference-video-to-video. With preserve_original_video on, this is the video-to-video amount: lower values keep more of the original video's pixels (e.g. 0.5 = keep ~50%), 1.0 fully regenerates. Without preserve_original_video it o…0 ≤ n ≤ 1 · default: 1
skip_control_preprocessbooleanSkip the built-in control estimation (depth / edge / pose) and use control_video_url directly as the control signal. Requires control_video_url; ignored if it is not set. With resolution='auto', the output follows the source video size/aspect up to the LTX lim…default: false
video_strengthnumberVideo conditioning strength. Lower values give the model more freedom to change the reference video motion/structure.0 ≤ n ≤ 1 · default: 0.6
generate_audiobooleanWhether to include audio in the returned video. When disabled, the final MP4 is returned without an audio track.default: true
video_qualityenumThe quality preset of the generated video.low | medium | high | maximum · default: "high"
negative_promptstringThe negative prompt to steer generation away from.default: "color distortion, overexposure,…
resolutionImageSize | enumThe size of the generated video. In direct-control mode (skip_control_preprocess with control_video_url), 'auto' follows the source video size/aspect up to the LTX limits and explicit sizes are honored with 64px alignment. In the built-in control estimation mo…default: "auto"
mid_image_urlstringOptional middle-frame keyframe image. When set, the look/appearance is anchored to this image around the middle of the clip (in addition to image_url at the start), so the appearance follows a moving camera instead of drifting. Requires image_url.nullable
control_video_urlstringOptional pre-computed control video (e.g. an already-rendered depth / edge / pose composite). When provided together with skip_control_preprocess, the built-in control estimation is skipped and this video is used directly as the control signal, resampled to the output resolution and frame count.nullable
video_write_modeenumThe write mode of the generated video.fast | balanced | small · default: "balanced"
image_urlstringOptional reference image for style/character anchoring. This is the FIRST-frame keyframe.nullable
end_image_urlstringOptional last-frame keyframe image. When set, the look/appearance is anchored to this image at the end of the clip. Useful for shots where the camera travels to a different place than the start image. Requires image_url.nullable

Types

2 $defs

ImageSizeobject

heightintegerThe height of the generated image.0 < n ≤ 14142 · default: 512
widthintegerThe width of the generated image.0 < n ≤ 14142 · default: 512

LoRAInputobject

A single LoRA to apply on top of the LTX-2.3 base model.

scalenumberStrength of the LoRA application (0.0 to 2.0). Higher values = stronger effect on the generated video.0 ≤ n ≤ 2 · default: 1
path*stringDirect HTTP(S) download URL of the LoRA file (.safetensors). The file is downloaded through an SSRF-safe downloader before it is loaded. Max size: 3 GB.length ≤ 2048
transformerenumForward-compatibility flag for multi-transformer architectures. LTX-2.3 has a single transformer, so 'both' is the right choice for almost all users.high | low | both · default: "both"

Validate a payload

before you spend tokens
shell
$ curl -X POST https://modelschemas.com/v1/validate \
    -d '{"provider":"fal","endpointId":"fal-ai/ltx-2.3-quality/reference-video-to-video/lora","payload":{…}}'
→ {"valid": false, "errors": [{"path": "#", "keyword": "required", …}]}