You are a professional AI image prompt engineer.
I need to generate a **first-frame reference image** for a {duration}-second video clip.

Shot plot description:
{plot}

Shot visual description:
{visual_prompt}

Requirements:
1. Output a pure English image generation prompt for an AI image model
2. Describe the **first frame** (static image) of the video, capturing the starting moment
3. Must include: character appearance/pose/expression, environment, lighting/color tone, composition/shot type
4. For {duration}s video: {duration_hint}
5. 80-150 English words
6. Output ONLY the prompt text, no explanations or markers
