GET

/v1/schemas/fal/video/fal-ai/ltx-2.3-quality/extend-video/lora

kind inputactivity videohash 820bb921…extracted Jul 9, 2026version currentsource upstream spec ↗
fieldrecorded source
schemaSource linked above.
Source trace
99b9388fa47f29845aade2f0b0393264d340ff17f23e234878ed8e2b62d3fef6
{
  "fetchedAt": 1783573357,
  "extractorVersion": "1",
  "verifiedAt": null
}

Request body

22 properties · 3 required · 2 $defs
propertytypedescriptionconstraints
video_url*stringThe URL of the video to extend.
prompt*stringThe prompt describing how the video should continue.
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
match_input_fpsbooleanWhen enabled, the output FPS matches the source video's FPS (rounded to an integer and clamped to the supported range) instead of frames_per_second.default: true
video_qualityenumThe quality preset of the generated video.low | medium | high | maximum · default: "high"
num_inference_stepsintegerNumber of inference steps. Defaults to 15 and can be increased up to 30.8 ≤ n ≤ 30 · default: 15
end_image_strengthnumberConditioning strength of the optional end keyframe. 1.0 = exact match, lower = more freedom for the model.0 ≤ n ≤ 1 · default: 1
generate_audiobooleanWhether to generate new audio for the extension segment (crossfaded with the source audio at the seam). When disabled, the source video's own audio track is preserved and the extension stays silent.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
enable_prompt_expansionbooleanWhether to enable prompt expansion.default: true
num_context_framesintegerThe number of source frames used as context/overlap for the extension. Snapped down to the LTX temporal grid (8k+1) and clamped to the frames available in the source video.9 ≤ n ≤ 121 · default: 25
negative_promptstringThe negative prompt to steer generation away from.default: "color distortion, overexposure,…
frames_per_secondnumberFrames per second of the generated video.1 ≤ n ≤ 60 · default: 24
guidance_scalenumberClassifier-free guidance scale. The default is tuned for fast, high-quality generation.1 ≤ n ≤ 20 · default: 1
seedintegerRandom seed for reproducibility. If None, a random seed is chosen.nullable
enable_safety_checkerbooleanWhether to enable the safety checker.default: true
resolutionImageSize | enumThe size of the generated video. 'auto' follows the source video size/aspect up to the LTX limits; the source is scaled to the final size in the stitched output. Sizes are 32px-aligned (e.g. 1920x1080 is delivered as 1888x1056). Higher resolutions reduce the m…default: "auto"
video_strengthnumberConditioning strength of the source context frames. 1.0 keeps the overlap locked to the source for a seamless transition; lower values give the model more freedom.0 ≤ n ≤ 1 · default: 1
video_write_modeenumThe write mode of the generated video.fast | balanced | small · default: "balanced"
num_framesintegerThe number of frames to generate for the extension segment, including num_context_frames of overlap with the source video. The new content adds approximately (num_frames - num_context_frames) / frames_per_second seconds. The stable generation budget caps the r…9 ≤ n ≤ 481 · default: 121
end_image_urlstringOptional keyframe image for the far end of the extension: the final frame for forward extension, or the new first frame for backward extension.nullable
extend_directionenumDirection to extend the video. 'forward' continues from the end of the video, 'backward' generates a new beginning.forward | backward · default: "forward"

Types

2 $defs

ImageSizeobject

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

LoRAInputobject

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

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"
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

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/extend-video/lora","payload":{…}}'
→ {"valid": false, "errors": [{"path": "#", "keyword": "required", …}]}