Generate videos via LTX-2.3 API (ltx.video). Supports text-to-video, image-to-video, audio-to-video (lip-sync from audio + image), extend, and retake. Use when: generating AI video from text/image/audio, animating a portrait, creating lip-sync video from an existing image + audio recording.
Base URL: https://api.ltx.video/v1
Auth: Authorization: Bearer <API_KEY>
Response: MP4 binary (direct download, no polling)
| Endpoint | Input | Use |
|---|---|---|
/v1/text-to-video | prompt | Generate video from text |
/v1/image-to-video | image_uri + prompt | Animate a still image |
/v1/audio-to-video | audio_uri + image_uri + prompt | Lip-sync video from audio + image |
/v1/extend | video_uri + prompt | Extend a video at start or end |
/v1/retake | video_uri + time range |
| Regenerate a section of a video |
| Model | Speed | Quality |
|---|---|---|
ltx-2-3-fast | ~17s | Good (use for tests) |
ltx-2-3-pro | ~30-60s | Best (use for final) |
1920x1080 (landscape 16:9)1080x1920 (portrait 9:16 — native vertical, trained on vertical data)1440x1080, 4096x2160 (text-to-video only)audio-to-video only supports: 1920x1080 or 1080x1920
curl -X POST "https://api.ltx.video/v1/text-to-video" \
-H "Authorization: Bearer $LTX_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"prompt": "A man in a navy blue suit sits at a luxury restaurant table...",
"model": "ltx-2-3-pro",
"duration": 8,
"resolution": "1920x1080"
}' -o output.mp4
curl -X POST "https://api.ltx.video/v1/audio-to-video" \
-H "Authorization: Bearer $LTX_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"audio_uri": "https://example.com/voice.mp3",
"image_uri": "https://example.com/portrait.jpg",
"prompt": "A man speaks directly to camera...",
"model": "ltx-2-3-pro",
"resolution": "1920x1080"
}' -o output.mp4
import requests
def ltx_audio_to_video(audio_url, image_url, prompt, api_key,
model="ltx-2-3-pro", resolution="1920x1080",
output_path="output.mp4"):
r = requests.post(
"https://api.ltx.video/v1/audio-to-video",
headers={"Authorization": f"Bearer {api_key}",
"Content-Type": "application/json"},
json={"audio_uri": audio_url, "image_uri": image_url,
"prompt": prompt, "model": model, "resolution": resolution},
timeout=300, stream=True
)
if r.status_code != 200:
raise RuntimeError(f"LTX error {r.status_code}: {r.text}")
with open(output_path, "wb") as f:
for chunk in r.iter_content(8192): f.write(chunk)
return output_path
application/octet-stream)curl -F "files[][email protected]" https://uguu.se/uploadaudio/mpeg ✅# Upload MP3 to uguu.se
AUDIO_URL=$(curl -s -F "files[][email protected]" "https://uguu.se/upload" | \
python3 -c "import sys,json; print(json.load(sys.stdin)['files'][0]['url'])")
# Upload image
IMAGE_URL=$(curl -s -F "files[][email protected]" "https://uguu.se/upload" | \
python3 -c "import sys,json; print(json.load(sys.stdin)['files'][0]['url'])")
# Resize large images before upload
ffmpeg -y -i input_4k.png -vf "scale=1920:1080" output_1080.jpg
/v1/extend to chain themLTX-2.3 has a much stronger text connector. Specificity wins.
❌ "A dramatic portrait of a man standing"
✅ "A man stands on a rooftop. His coat flaps in the wind. He adjusts his collar and steps forward as the camera tracks right."
"His voice is clear and warm. Restaurant ambient sound softly in the background.""Individual hair strands visible in the backlight" → now renders correctlyresolution: "1080x1920" → trained on vertical data"He picks up the banana, raises it to his ear, and smirks"A [description of person] sits/stands [location]. He/she speaks directly
to camera, lips moving in perfect sync with his/her voice. [Gesture details].
Head stays level and gaze remains locked on camera throughout.
[Environment description softly blurred in background].
[Lighting]. [Camera: holds steady at eye level, front-on].
Custom nodes for ComfyUI (no manual API calls):
cd ComfyUI/custom_nodes
git clone https://github.com/PauldeLavallaz/comfyui-ltx-node
Nodes: LTX Text to Video, LTX Image to Video, LTX Extend Video
Category: LTX Video
Paul's key: stored in ~/clawd/.env as LTX_API_KEY
ltxv_RfSU5hdKJb_g5dwbECZWnilE1P8dJzbavz6niP_0LQJ942ARHIVhrBCfebcytEL1efLVx_63S_PJyWTzicrBcWEkOXfCbGTl8JSzlJJk329MwRViEgOoE2KnE9LIA5t6QSFeBy7DLnTIcX0AZNbV9Jv0TuC7qcq2gV33G6ROhUVUDCuN