{"$schema":"https://json-schema.org/draft/2020-12/schema","type":"object","properties":{"prompt":{"type":"string","maxLength":2000,"description":"Text prompt describing the video to generate"},"image":{"description":"Reference image (HTTP(S) URL or base64 data URI) for image-to-video","type":"string"},"reference_video":{"description":"Reference video (HTTP(S) URL or base64 data URI) for style/motion guidance","type":"string"},"last_frame_image":{"description":"Reference image (HTTP(S) URL or base64 data URI) for last-frame guidance. Only works if an image start frame is also given.","type":"string"},"reference_images":{"description":"Reference images (1-4, HTTP(S) URLs or base64 data URIs) to guide video generation for characters, avatars, clothing, or environments. Cannot be used with first/last frame images.","maxItems":4,"type":"array","items":{"type":"string"}},"duration":{"default":5,"description":"Video duration in seconds","type":"integer","minimum":4,"maximum":12},"resolution":{"default":"720p","description":"Video resolution","type":"string","enum":["480p","720p"]},"aspect_ratio":{"default":"16:9","description":"Video aspect ratio. Ignored if an image is used.","type":"string","enum":["16:9","4:3","1:1","3:4","9:16","21:9","9:21"]},"fps":{"default":24,"description":"Frame rate (frames per second)","type":"number","const":24},"camera_fixed":{"default":false,"description":"Whether to fix camera position","type":"boolean"},"generate_audio":{"description":"Whether to generate audio with the video","type":"boolean"},"watermark":{"default":false,"description":"Whether to add a watermark to the output video","type":"boolean"},"seed":{"description":"Random seed for reproducible generation","type":"integer","minimum":-9007199254740991,"maximum":9007199254740991},"use_virtual_avatar":{"default":false,"description":"Route image reference inputs (image, reference_images, last_frame_image) through ByteDance's trusted virtual avatar asset library before generation. Intended for AI-generated/virtual character avatars that would otherwise be blocked by face or deepfake detection","type":"boolean"},"reference_audio":{"description":"Reference audio (HTTP(S) URL or base64 data:audio/... URI) to use as background music. Must be accompanied by a reference image or video.","type":"string"}},"required":["prompt","duration","resolution","aspect_ratio","fps","camera_fixed","watermark","use_virtual_avatar"],"additionalProperties":false}