# Generate video > Start a video render on an explicit model, with optional frame inputs, and collect the file. `POST /video/generate` creates a video task. `model` and `prompt` are required. One request renders one video, and there is no `auto` or `count`. **SDK** ```ts import Mynth from "@mynthio/sdk"; const mynth = new Mynth(); const task = await mynth.video.generate({ model: "bytedance/seedance-2.0-mini", prompt: "A lighthouse beam sweeping over waves", duration: 5, size: "9:16_720p", }); console.log(task.urls[0]); ``` **REST** ```bash curl https://api.mynth.io/video/generate \ -H "Authorization: Bearer $MYNTH_API_KEY" \ -H "Content-Type: application/json" \ -d '{"model":"bytedance/seedance-2.0-mini","prompt":"A lighthouse beam sweeping over waves","duration":5,"size":"9:16_720p"}' ``` The REST call returns a `task_id` and `estimated_cost` at once. The SDK waits up to an hour. A render takes minutes, so in a request handler, create the task with `generateAsync()` and finish in a [webhook](https://mynth.io/docs/concepts/webhooks.md) instead of waiting. The CLI has no video command. ## Fields | Field | Notes | | ------------------------------ | --------------------------------------------------------------------------------------------------------------------------- | | `model` | Required. An id from [video models](https://mynth.io/docs/models/video.md) | | `prompt` | Required. 1 to 8192 characters | | `negative_prompt` | Optional. Up to 8192 characters | | `size` | Aspect ratio and resolution tier. Defaults to `auto`. See [sizes](#sizes) | | `duration` | Seconds. Defaults to the model's default. Each model accepts its own range | | `audio` | Generated audio. Defaults to the model's default, which is on for every current model | | `inputs` | Frame images. See [frame inputs](#frame-inputs) | | `webhook` | Per-request URLs, same shape as on images. See [webhooks](https://mynth.io/docs/concepts/webhooks.md#per-request-webhooks) | | `metadata` | A JSON object up to 2048 bytes | | `generate_public_access_token` | `true` returns a browser token as `public_access_token`. See [from a browser](https://mynth.io/docs/guides/poll-for-results.md#from-a-browser) | Video does not take `destination`, `count`, `magic_prompt`, or `output`. Sending any of them answers `400 validation_error`. Every value is checked against the model when the task is created. A resolution tier, duration, audio setting, or input the model does not serve answers `400 validation_error`, and nothing is queued. ## Sizes You ask for a shape and a resolution tier, not pixels. The shapes are the same as for [images](https://mynth.io/docs/guides/generate-images.md#sizes), and Mynth picks the closest aspect ratio the model serves. The tier is not adjusted: it sets the price, so a tier the model does not serve answers `400 validation_error`. | `size` | Result | | ------------------------------------------------------------------------------------- | ------------------------------------------------ | | `auto`, or no `size` | the model's default shape and tier | | `square`, `portrait`, `landscape`, `portrait_tall`, `landscape_wide` | 1:1, 2:3, 3:2, 9:16, 16:9 | | `1:1`, `2:3`, `3:2`, `3:4`, `4:3`, `4:5`, `5:4`, `9:16`, `16:9`, `21:9`, `2:1`, `1:2` | that ratio | | Any of the above with `_480p`, `_720p`, `_1080p`, or `_4k`, such as `9:16_1080p` | that shape at that tier | | `{ "type": "aspect_ratio", "aspect_ratio": "9:16", "resolution": "1080p" }` | the same, as an object. `resolution` is optional | | `{ "type": "auto", "resolution": "1080p" }` | the model's default shape at that tier | With a first frame, the frame sets the shape and the aspect ratio is ignored. The tier still applies. The result's `aspect_ratio` is the ratio the video was rendered at, or `null` when the frame set it. ## Frame inputs Send `inputs` to animate from an image. Each input is a URL string or an object with a role: ```json { "model": "bytedance/seedance-2.0-mini", "prompt": "The camera pulls back from the lighthouse", "inputs": [ { "type": "image", "as": "first_frame", "source": { "type": "url", "url": "https://cdn.example.com/start.png" } }, { "type": "image", "as": "last_frame", "source": { "type": "url", "url": "https://cdn.example.com/end.png" } } ] } ``` Every current model needs exactly one `first_frame` for image-to-video. Seedance and Gemini Omni Flash also take an optional `last_frame`. P-Video and Grok Imagine Video take the first frame only. [Video models](https://mynth.io/docs/models/video.md) has the table, and `modes` on the catalog entry is the live contract. ## What comes back ```json { "model": "bytedance/seedance-2.0-mini", "videos": [ { "status": "success", "id": "vid_3HkP9wQz7LmR2tXc8VbN5dFy0JsA4gUe", "url": "https://cdn.mynth.io/videos/vid_3HkP9wQz7LmR2tXc8VbN5dFy0JsA4gUe.mp4", "mynth_url": "https://cdn.mynth.io/videos/vid_3HkP9wQz7LmR2tXc8VbN5dFy0JsA4gUe.mp4", "cost": "0.40500000", "duration": 5, "resolution": "720p", "aspect_ratio": "9:16", "audio": true } ] } ``` Check `status` on the video. A refusal or a provider failure fails the item with an `error.code` while the task still completes. The file is served for 7 days. See [tasks](https://mynth.io/docs/concepts/tasks.md#file-lifetimes). ## Price Video is `per_second[tier] × duration`, where `tier` is the resolution in `size`, and the estimate is exact because the model is explicit. Price a body with `POST /video/generate/estimate`, or `mynth.video.estimate()` in the SDK. [Pricing](https://mynth.io/docs/pricing.md#video-price) has the formula. ## Next steps - [Video models](https://mynth.io/docs/models/video.md): resolutions, durations, and frame inputs per model. - [Webhooks](https://mynth.io/docs/concepts/webhooks.md): collect a long render without holding a connection. - [Poll for results](https://mynth.io/docs/guides/poll-for-results.md): the status and result calls.