VideoMetadata

{
    "ratio": "16:9",
    "resolution": "480p",
    "seed": 42,
    "watermark": false,
    "camera_fixed": false,
    "content": [
        {
            "type": "text",
            "text": "宇航员站起身，回望地球",
            "image_url": {
                "url": "https://example.com/reference-photo.jpg"
            },
            "video_url": {
                "url": "https://example.com/input-video-clip.mp4"
            }
        }
    ],
    "return_last_frame": false,
    "generate_audio": false,
    "draft": false,
    "service_tier": "default",
    "callback_url": "https://your-server.com/webhook/video-callback"
}