# Veo 3.1 Fast > Generate videos from a first/last frame using Google's Veo 3.1 Fast ## Overview - **Endpoint**: `https://fal.run/fal-ai/veo3.1/fast/first-last-frame-to-video` - **Model ID**: `fal-ai/veo3.1/fast/first-last-frame-to-video` - **Category**: image-to-video - **Kind**: inference ## Pricing For every second of video you generate you will be charged **$0.10** without audio or **$0.15** with audio for 720p or 1080p. At 4k, you will be charged **$0.30** per second without audio, or **$0.35** with. For example, a **5 second video** at **1080p** with **audio on** will cost **$0.75**. For more details, see [fal.ai pricing](https://fal.ai/pricing). ## API Information This model can be used via our HTTP API or more conveniently via our client libraries. See the input and output schema below, as well as the usage examples. ### Input Schema The API accepts the following input parameters: - **`prompt`** (`string`, _required_): The text prompt describing the video you want to generate - Examples: "A woman looks into the camera, breathes in, then exclaims energetically, \"have you guys checked out Veo3.1 First-Last-Frame-to-Video on Fal? It's incredible!\"" - **`aspect_ratio`** (`AspectRatioEnum`, _optional_): The aspect ratio of the generated video. Default value: `"auto"` - Default: `"auto"` - Options: `"auto"`, `"16:9"`, `"9:16"` - **`duration`** (`DurationEnum`, _optional_): The duration of the generated video. Default value: `"8s"` - Default: `"8s"` - Options: `"4s"`, `"6s"`, `"8s"` - **`negative_prompt`** (`string`, _optional_): A negative prompt to guide the video generation. - **`resolution`** (`ResolutionEnum`, _optional_): The resolution of the generated video. Default value: `"720p"` - Default: `"720p"` - Options: `"720p"`, `"1080p"`, `"4k"` - **`generate_audio`** (`boolean`, _optional_): Whether to generate audio for the video. Default value: `true` - Default: `true` - **`seed`** (`integer`, _optional_): The seed for the random number generator. - **`auto_fix`** (`boolean`, _optional_): Whether to automatically attempt to fix prompts that fail content policy or other validation checks by rewriting them. - Default: `false` - **`safety_tolerance`** (`SafetyToleranceEnum`, _optional_): The safety tolerance level for content moderation. 1 is the most strict (blocks most content), 6 is the least strict. Default value: `"4"` - Default: `"4"` - Options: `"1"`, `"2"`, `"3"`, `"4"`, `"5"`, `"6"` - **`first_frame_url`** (`string`, _required_): URL of the first frame of the video - Examples: "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-1.jpeg" - **`last_frame_url`** (`string`, _required_): URL of the last frame of the video - Examples: "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-2.jpeg" **Required Parameters Example**: ```json { "prompt": "A woman looks into the camera, breathes in, then exclaims energetically, \"have you guys checked out Veo3.1 First-Last-Frame-to-Video on Fal? It's incredible!\"", "first_frame_url": "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-1.jpeg", "last_frame_url": "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-2.jpeg" } ``` **Full Example**: ```json { "prompt": "A woman looks into the camera, breathes in, then exclaims energetically, \"have you guys checked out Veo3.1 First-Last-Frame-to-Video on Fal? It's incredible!\"", "aspect_ratio": "auto", "duration": "8s", "resolution": "720p", "generate_audio": true, "safety_tolerance": "4", "first_frame_url": "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-1.jpeg", "last_frame_url": "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-2.jpeg" } ``` ### Output Schema The API returns the following output format: - **`video`** (`File`, _required_): The generated video. - Examples: {"url":"https://storage.googleapis.com/falserverless/example_outputs/veo31-flf2v-output.mp4"} **Example Response**: ```json { "video": { "url": "https://storage.googleapis.com/falserverless/example_outputs/veo31-flf2v-output.mp4" } } ``` ## Usage Examples ### cURL ```bash curl --request POST \ --url https://fal.run/fal-ai/veo3.1/fast/first-last-frame-to-video \ --header "Authorization: Key $FAL_KEY" \ --header "Content-Type: application/json" \ --data '{ "prompt": "A woman looks into the camera, breathes in, then exclaims energetically, \"have you guys checked out Veo3.1 First-Last-Frame-to-Video on Fal? It's incredible!\"", "first_frame_url": "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-1.jpeg", "last_frame_url": "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-2.jpeg" }' ``` ### Python Ensure you have the Python client installed: ```bash pip install fal-client ``` Then use the API client to make requests: ```python import fal_client def on_queue_update(update): if isinstance(update, fal_client.InProgress): for log in update.logs: print(log["message"]) result = fal_client.subscribe( "fal-ai/veo3.1/fast/first-last-frame-to-video", arguments={ "prompt": "A woman looks into the camera, breathes in, then exclaims energetically, \"have you guys checked out Veo3.1 First-Last-Frame-to-Video on Fal? It's incredible!\"", "first_frame_url": "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-1.jpeg", "last_frame_url": "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-2.jpeg" }, with_logs=True, on_queue_update=on_queue_update, ) print(result) ``` ### JavaScript Ensure you have the JavaScript client installed: ```bash npm install --save @fal-ai/client ``` Then use the API client to make requests: ```javascript import { fal } from "@fal-ai/client"; const result = await fal.subscribe("fal-ai/veo3.1/fast/first-last-frame-to-video", { input: { prompt: "A woman looks into the camera, breathes in, then exclaims energetically, \"have you guys checked out Veo3.1 First-Last-Frame-to-Video on Fal? It's incredible!\"", first_frame_url: "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-1.jpeg", last_frame_url: "https://storage.googleapis.com/falserverless/example_inputs/veo31-flf2v-input-2.jpeg" }, logs: true, onQueueUpdate: (update) => { if (update.status === "IN_PROGRESS") { update.logs.map((log) => log.message).forEach(console.log); } }, }); console.log(result.data); console.log(result.requestId); ``` ## Additional Resources ### Documentation - [Model Playground](https://fal.ai/models/fal-ai/veo3.1/fast/first-last-frame-to-video) - [API Documentation](https://fal.ai/models/fal-ai/veo3.1/fast/first-last-frame-to-video/api) - [OpenAPI Schema](https://fal.ai/api/openapi/queue/openapi.json?endpoint_id=fal-ai/veo3.1/fast/first-last-frame-to-video) ### fal.ai Platform - [Platform Documentation](https://docs.fal.ai) - [Python Client](https://docs.fal.ai/clients/python) - [JavaScript Client](https://docs.fal.ai/clients/javascript)