Models / LTX / Start & end frame

LTX start & end frame prompting guide

How to prompt LTX in start/end frame mode. Every point links its source; community tips are marked. Your agent gets the same guide through the Atlas MCP (get_guide).

Prompt structure

path between frames→camera→pacing beats→audio

• Establish the shot (cinematography, scale); set the scene (light, palette, texture, atmosphere); action as a flowing sequence with active verbs; characters with emotion shown physically; camera movement and how subjects look after it; audio. source ↗

What the text should describe

• image_uri + last_frame_uri: the clip interpolates between them; set an explicit duration (auto-length not allowed with a last frame). source ↗
• Write the beats and pauses you want into the prompt ('she pauses', 'a beat of silence'); LTX won't add pauses you didn't prompt. source ↗

Responds well to

• Best: cinematic single-subject scenes, clear camera language, consistent lighting, described audio; dialogue in quotes with language/accent. source ↗

Duration and limits

• API: generate_audio default true; fps default 24; retake section ≥2 s on inputs ≥73 frames; extend 2–20 s (context+duration ≤505 frames); audio-to-video length follows the audio. source ↗

Multi-shot

• Several shots joined by explicit cuts; re-establish framing, identity and audio at each cut. source ↗
• At every cut say whether music/dialogue/ambience continues or changes, and re-identify subjects. source ↗

Avoid and failure modes

• On-screen text spelling not guaranteed; chaotic physics causes artifacts. source ↗
• Don't paste a Kling/Seedance prompt into LTX unchanged: tag syntax and shot-list formatting don't carry over. Aim for ~4–8 descriptive sentences, present tense. source ↗

Negative prompt

Supported via .

Next

Sources

• docs-dev.ltx.io/open-source-model/usage-guides/prompting-guide.md
• docs.ltx.io/api-documentation/api-reference/async-video-generation/submit-extend.md
• docs.ltx.io/api-documentation/api-reference/async-video-generation/submit-image-to-video.m
• docs.ltx.io/api-documentation/implementation-guides/prompting-guide.md