> ## Documentation Index > Fetch the complete documentation index at: https://docs.modellix.ai/llms.txt > Use this file to discover all available pages before exploring further. # Vidu Q4 R2V > [Core Function] Vidu Q4 R2V is the preview reference-to-video model that composes a new 3-16 second clip from 1 to 15 reference images while keeping subject appearance consistent. [Strengths] It supports 540p through 4K, aspect ratios including 3:4 and 4:3, synchronized audio, and up to three reference audio clips. [Best For] Highly recommended for: multi-image character consistency, vertical 3:4 portraits, and scenes that combine reference images with spoken audio. [Limitations] Do NOT use this model to animate one image exactly as the first frame; use Vidu Q4 I2V for that. Do NOT omit the prompt. Do NOT send more than 15 images or more than 3 audio files. Subject-library invocation is not supported. [Routing] Use this model when the user supplies reference images and a prompt for a newly composed shot. Use Vidu Q4 I2V for a single start frame. ## OpenAPI ````yaml /media-model-api/vidu/vidu-i2v.json post /vidu/viduq4-r2v openapi: 3.1.0 info: description: >- The image-to-video models API from Vidu. Includes standard I2V, Q2-NS template I2V, first-last frame, reference-to-video, digital human, multi-frame animation, template story, and one-click film/ad generation. version: 1.0.0 contact: name: Modellix Support email: support@modellix.ai title: Vidu Image-to-Video Models API servers: - url: https://api.modellix.ai/api/v1 description: The image-to-video models API from Vidu. security: - bearerAuth: [] paths: /vidu/viduq4-r2v: post: summary: Vidu Q4 R2V description: >- [Core Function] Vidu Q4 R2V is the preview reference-to-video model that composes a new 3-16 second clip from 1 to 15 reference images while keeping subject appearance consistent. [Strengths] It supports 540p through 4K, aspect ratios including 3:4 and 4:3, synchronized audio, and up to three reference audio clips. [Best For] Highly recommended for: multi-image character consistency, vertical 3:4 portraits, and scenes that combine reference images with spoken audio. [Limitations] Do NOT use this model to animate one image exactly as the first frame; use Vidu Q4 I2V for that. Do NOT omit the prompt. Do NOT send more than 15 images or more than 3 audio files. Subject-library invocation is not supported. [Routing] Use this model when the user supplies reference images and a prompt for a newly composed shot. Use Vidu Q4 I2V for a single start frame. operationId: viduQ4R2VAsync requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/ViduQ4R2VRequest' examples: basic: summary: One reference image value: prompt: The character waves hello. reference_images: - https://example.com/subject.jpg portrait: summary: Portrait ratio with reference audio value: prompt: The character speaks to the camera. reference_images: - https://example.com/subject.jpg audio_urls: - https://example.com/voice.mp3 aspect_ratio: '3:4' duration: 3 resolution: 540p audio: true responses: '200': description: Task submitted successfully content: application/json: schema: $ref: '#/components/schemas/AsyncTaskResponse' example: code: 0 message: success data: status: pending task_id: task-vidu-q4-r2v-001 model_id: vidu/viduq4-r2v get_result: method: GET url: https://api.modellix.ai/api/v1/tasks/task-vidu-q4-r2v-001 '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '429': $ref: '#/components/responses/TooManyRequests' '500': $ref: '#/components/responses/InternalServerError' components: schemas: ViduQ4R2VRequest: type: object required: - prompt - reference_images description: >- Vidu Q4 Preview reference-to-video request. Requires a prompt and 1-15 reference images. properties: prompt: type: string minLength: 1 maxLength: 20000 description: >- Required scene description, up to 20000 characters. Reference tokens such as [@reference_image_1] are passed through unchanged. example: In the scene, the character waves hello. reference_images: type: array minItems: 1 maxItems: 15 description: >- Reference image URLs, 1 to 15. Appearance is preserved while the prompt defines the new action. items: type: string minLength: 1 example: - https://example.com/subject.jpg audio_urls: type: array maxItems: 3 description: Optional reference audio URLs, up to 3 mp3 files. items: type: string minLength: 1 example: - https://example.com/voice.mp3 audio: type: boolean default: true description: >- Whether to generate audio with the video. Default true. Set false for a silent video. example: true duration: type: integer minimum: 3 maximum: 16 default: 5 description: 'Video duration in seconds. Default 5. Allowed range: 3-16.' example: 5 aspect_ratio: type: string enum: - '16:9' - '9:16' - '1:1' - '3:4' - '4:3' default: '16:9' description: Output aspect ratio. Default 16:9. example: '3:4' resolution: type: string enum: - 540p - 720p - 1080p - 2K - 4K default: 720p description: >- Video resolution. Default 720p. Allowed values: 540p, 720p, 1080p, 2K, 4K. example: 720p seed: type: integer description: Random seed. Omit or use 0 for a random seed. example: 1 AsyncTaskResponse: type: object required: - code - message - data properties: code: type: integer description: Response code, 0 indicates success example: 0 message: type: string description: Response message example: success data: type: object required: - status - task_id - model_id properties: status: type: string enum: - pending - processing description: Task status example: pending task_id: type: string description: Unique task identifier for polling example: task-abc123 model_id: type: string description: Model ID in `provider/model` format example: vidu/viduq3-pro-fast-i2v get_result: type: object description: API information to query the task result properties: method: type: string example: GET url: type: string example: https://api.modellix.ai/api/v1/tasks/task-abc123 description: Detailed data about the submitted asynchronous task. ErrorResponse: type: object required: - code - message properties: code: type: integer example: 400 message: type: string example: 'Invalid parameters: parameter ''first_frame_image'' is required' responses: BadRequest: description: Invalid request parameters content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: code: 400 message: 'Invalid parameters: parameter ''first_frame_image'' is required' Unauthorized: description: Unauthorized - Invalid or missing API Key content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: code: 401 message: 'Authentication failed: invalid API key' TooManyRequests: description: Too many requests - Rate limit exceeded headers: X-RateLimit-Limit: description: Maximum requests per minute schema: type: integer example: 100 X-RateLimit-Remaining: description: Remaining quota in current window schema: type: integer example: 0 X-RateLimit-Reset: description: Rate limit window reset time (Unix timestamp) schema: type: integer example: 1704067260 content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: code: 429 message: >- Rate limit exceeded: 100 requests per minute, retry after 60 seconds InternalServerError: description: Internal server error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: code: 500 message: Internal server error securitySchemes: bearerAuth: type: http scheme: bearer description: 'API Key authentication. Format: `Bearer YOUR_API_KEY`.' ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.