# google-video (Google Video)

This example demonstrates Google Veo video generation models for AI-powered video creation from text prompts.

You can run this example with:

```bash
npx promptfoo@latest init --example google-video
cd google-video
```

## Prerequisites

Choose one:

- Google AI Studio / Gemini API key
- Google Cloud project with Vertex AI API enabled and authentication via `gcloud auth application-default login`

## Setup

```bash
# Option 1: Google AI Studio / Gemini API
export GOOGLE_API_KEY=your-api-key

# Option 2: Vertex AI
gcloud services enable aiplatform.googleapis.com
gcloud auth application-default login
export GOOGLE_PROJECT_ID=your-project-id
```

## Environment Variables

- `GOOGLE_API_KEY` - Google AI Studio / Gemini API key
- `GOOGLE_PROJECT_ID` - Google Cloud project ID for Vertex AI

## Available Models

| Model                      | Description                         | Duration |
| -------------------------- | ----------------------------------- | -------- |
| `veo-3.1-generate-preview` | Latest with video extension support | 4, 6, 8s |
| `veo-3.1-fast-preview`     | Fast Veo 3.1                        | 4, 6, 8s |
| `veo-3-generate`           | Veo 3.0 standard                    | 4, 6, 8s |
| `veo-3-fast`               | Veo 3.0 fast                        | 4, 6, 8s |
| `veo-2-generate`           | Veo 2.0                             | 5, 6, 8s |

## Running the Example

```bash
npx promptfoo@latest eval
```

## Configuration Options

| Option             | Type   | Description                                                     |
| ------------------ | ------ | --------------------------------------------------------------- |
| `aspectRatio`      | string | `16:9` (default) or `9:16`                                      |
| `resolution`       | string | `720p` (default) or `1080p`                                     |
| `durationSeconds`  | number | Duration: 4, 6, 8 for Veo 3.x; 5, 6, 8 for Veo 2                |
| `personGeneration` | string | `allow_adult` or `dont_allow`                                   |
| `negativePrompt`   | string | Concepts to avoid                                               |
| `image`            | string | Source image for image-to-video                                 |
| `lastImage`        | string | End frame for interpolation                                     |
| `extendVideoId`    | string | Operation ID from previous Vertex Veo generation (Veo 3.1 only) |
| `referenceImages`  | array  | Up to 3 style reference images (file paths or objects)          |

## Features

### Text-to-Video

Generate videos from text prompts (see `promptfooconfig.yaml`).

### Image-to-Video

Generate videos from a starting image (see `promptfooconfig-image.yaml`).

### Video Extension (Veo 3.1)

Extend previously generated Veo videos using the explicit Vertex provider path and an operation ID (see `promptfooconfig-extension.yaml`).

## Notes

- Generated videos are stored in promptfoo's blob storage system
- Videos use content-addressable hashing for automatic deduplication
- Use `--no-cache` flag to force regeneration
- Videos are served via the local server for viewing in the UI
- Veo models use long-running operations with polling for completion
- `google:video:*` uses Google AI Studio by default and auto-detects Vertex AI when project-based auth is configured
- Existing project-based `google:video:*` configs remain compatible, but `vertex:video:*` is the recommended explicit path for Vertex-only flows such as `extendVideoId`