How to generate 4K video through an API
RelayDance provides an OpenAI-compatible API for generating 4K video using models like ByteDance Seedance 2.0, Seedance 1.5 Pro, and HappyHorse video models. Submit video generation requests via POST to the /v1/video/generations endpoint with your desired model, prompt, duration, and resolution settings. The API supports both polling and webhook-based completion notification, allowing you to retrieve your generated video URL once processing finishes. Authentication uses bearer token authorization with API keys created in your RelayDance console account.
Setting up authentication and API access
To generate videos through RelayDance, you need an active API key from your account. Visit https://relaydance.com/console to create and manage your API keys. Use the base URL https://relaydance.com/v1 for all requests, and include your key in the Authorization header as "Bearer YOUR_API_KEY". RelayDance accepts payments via USDT and Stripe card, with pricing available at https://relaydance.com/models. Failed or errored requests incur no charges, so you only pay for successful video generations. Refer to https://relaydance.com/docs for complete endpoint documentation and implementation examples.
Submitting a video generation request
To generate 4K video, send a POST request to /v1/video/generations with the following parameters: model (such as "seedance-2.0"), prompt (your description), seconds (duration), and metadata containing ratio, resolution, generate_audio, callback_url, and content references. The metadata.content[] array accepts up to 9 reference images, 3 reference videos, and 3 audio tracks per request. Reference any media in your prompt using @image1 through @imageN notation. Individual clips can be up to 15 seconds long. The endpoint returns a task_id that you use to track generation progress.
Tracking completion and retrieving results
RelayDance supports two completion workflows. In polling mode, repeatedly call GET /v1/video/generations/{task_id} at regular intervals until the status field indicates "succeeded" or "failed". The response includes your video URL upon success. Alternatively, use webhook mode by specifying metadata.callback_url in your initial request. The API will POST the final completion state to your server, eliminating the need for polling. Either method ensures you receive notification when your 4K video is ready for download and use.
Available video models and features
RelayDance offers multiple video generation models optimized for different use cases. ByteDance Seedance 2.0 and Seedance 1.5 Pro provide advanced video synthesis, while HappyHorse video models and Grok Imagine video models cover additional generation styles. The platform also includes Grok text models and image generation via POST /v1/images/generations. Mainstream model groups are priced 30 percent or more below official list rates. Check https://relaydance.com/models for current per-model pricing and capabilities to select the best fit for your 4K video project.
| Video Generation Workflow Step | Action |
|---|---|
| 1. Authenticate | Create API key at https://relaydance.com/console and prepare Bearer token |
| 2. Prepare request | Define model, prompt, duration (seconds), resolution, and reference media in metadata.content[] |
| 3. Submit video task | POST to /v1/video/generations with all parameters; receive task_id |
| 4. Track progress | Poll GET /v1/video/generations/{task_id} or use webhook callback_url |
| 5. Retrieve video | Download video URL from response when status is "succeeded" |
FAQ
- What resolution options are available for 4K video generation? RelayDance accepts resolution parameters in your metadata object. Specific supported resolutions are documented at https://relaydance.com/docs; submit your desired resolution in the request and the API will process accordingly.
- Can I reference existing images or videos in my prompts? Yes. Include up to 9 reference images, 3 reference videos, and 3 audio tracks in metadata.content[]. Cite them in your prompt using @image1, @image2, and similar notation (up to @image9). Video and audio clips can be up to 15 seconds each.
- How much does 4K video generation cost? Pricing varies by model and is available at https://relaydance.com/models. RelayDance typically offers mainstream models at 30 percent or more below official rates. You pay only for successful generations, not for failed or errored requests.