Introduction
LTX 2.3 Spicy LoRA Video extend continues a clip you already have. Send it as video_url, with a prompt if you want to steer what happens next. The final frame of your clip becomes the opening frame of a new LTX 2.3 Spicy LoRA image-to-video shot of 3 to 20 seconds, and the two are joined into one MP4: your original first, then the continuation, with the repeated seam frame removed. The new segment also comes back as its own file, so you can keep extending or edit the pieces separately.
Key features & highlights
Continuity comes from the last frame. Wardrobe, set, light and where everyone stands carry over because the new segment literally starts on your final frame. Motion does not carry over the same way: the model sees one still, not the whole clip, so describe the movement you want to continue instead of assuming it will keep its speed or direction.
One file back, plus the new piece on its own. The joined MP4 keeps your clip’s frame rate and its framing, with no black bars. To line the seam up, the picture may be trimmed or adjusted by a few percent at the edges. If the model returns a noticeably different shape, the new segment is scaled to fill your frame and centered, cropping what spills over. The file is encoded as H.264 MP4 with AAC sound. LTX 2.3 Spicy LoRA has no audio field, so the new segment often comes back silent or faint. The sound of your source stays; where one side has none, the joined file is filled with silence, and where both have sound they are blended over a short crossfade at the seam. The second asset in the output is the new segment alone, ready for another extend or for an editor.
Everything else is LTX 2.3 Spicy LoRA image-to-video. The new segment runs on the same routes, with the same content range and the same per-second price as the image-to-video endpoint, and a failed generation is refunded the same way. The preset and LoRA fields work as they do on image-to-video. If the generation succeeds but the join itself cannot be built, the task fails and the charge is refunded.
Request parameters
| Parameter | Required | Description |
|---|---|---|
preset | No | The default, tuned, applies the recommended general-purpose stack; original styles more lightly and stays closer to your last frame. |
prompt | No | Optional. What happens next: the action that follows and the camera move. |
loras | No | Up to three {path, scale} entries applied to the new segment on top of the preset: path is one of the thirteen built-in LoRA keys, scale its strength from 0 to 4 (default 1). at most 3 items |
duration_seconds | No | Length of the new segment: any whole number from 3 to 20 seconds, default 5. 20 seconds is one generation, not a stitched sequence. |
resolution | No | Resolution of the new segment: 480p, 720p or 1080p, default 480p. |
seed | No | 0 to 2147483647. Hold it steady to compare one changed field at a time; drop it for variety. |
video_url | Yes | The clip to continue: MP4, MOV or WebM, up to 60 seconds. Its final frame becomes the opening frame of the new segment, so cut it on a clean, sharp frame. at least 1 characters |
Pricing
Billed per second of the new segment at the resolution you choose; the source clip you send is not billed.
| Specification | Price |
|---|---|
| $0.0285 / second |
| $0.0475 / second |
| $0.0665 / second |
Use cases
Lengthen a shot that ended too early: a product turntable that stops before the label faces camera, or a walk that cuts before the subject reaches the door. Extend it by a few seconds and describe only the remaining motion.
Build a longer sequence step by step. Generate a first shot, extend it, then extend the joined result again; each step bills only the seconds it adds. Because every step starts from a single frame, watch each seam before stacking the next one.
Prompt guide & pro tips
Describe the next beat, not the whole scene, or leave the prompt empty. The frame already fixes who and where; if you write, spend the words on the action that follows and the camera move. Repeat the camera language your clip ended on, such as a slow push in or a locked shot, so the seam reads as one take.
Trim before you extend. The last frame is the only picture the model sees, so a blurred, mid-cut or heavily compressed ending carries straight into the continuation. Cut your source on a clean, sharp frame first. Sources of up to 60 seconds are accepted as MP4, MOV or WebM.
Keep the resolution consistent. The resolution only decides how sharp the new segment is generated, so a lower setting makes the new part look softer than the original. Match the resolution of your source, and set duration_seconds to the length you actually need: the charge follows the new segment only.
API quick start
# Generate the idempotency key once; reuse it when retrying after a lost response.
export SPICY_IDEMPOTENCY_KEY="${SPICY_IDEMPOTENCY_KEY:-$(uuidgen)}"
curl -X POST https://api.spicyapi.ai/api/v1/jobs/createTask \
-H "Authorization: Bearer $SPICY_API_KEY" \
-H "Content-Type: application/json" \
-H "Idempotency-Key: $SPICY_IDEMPOTENCY_KEY" \
-d '{
"model": "lightricks/ltx-2.3-spicy-lora/video-extend",
"input": {
"duration_seconds": 5,
"preset": "tuned",
"resolution": "480p",
"video_url": "https://example.com/reference.mp4"
}
}'
# Copy data.taskId from the response into TASK_ID, then poll the status.
TASK_ID="TASK_ID_FROM_RESPONSE"
curl "https://api.spicyapi.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
-H "Authorization: Bearer $SPICY_API_KEY"
See the API reference for authentication, the complete schema, polling, and error handling.





