# Luma Ray 3.2 - Core.Today AI API

> Luma's flagship Ray video model. Text-to-video and keyframe (start/end image) generation with optional HDR-encoded output and professional EXR export.

- **Provider**: Luma
- **Model ID**: luma/ray-3.2
- **Category**: Video Generation
- **Credits**: 1740 per video, tiered by resolution, duration, and HDR
- **Speed**: Medium
- **Quality**: Ultra

## Features
- Flagship text-to-video generation with detailed prompt control
- Keyframe mode using start/end images to anchor the first and last frame
- HDR-encoded MP4 output for wider dynamic range
- Professional EXR export alongside the MP4 for color-grading pipelines
- Seamless looping video option
- Multiple resolutions (540p/720p/1080p) and durations (5s/10s)

## Use Cases
- Professional/HDR footage for post-production color-grading pipelines
- Keyframe-driven brand or product shots with precise start/end composition
- Cinematic text-to-video content with detailed camera and lighting direction
- Seamlessly looping background visuals for websites or displays

## API Endpoint

Base URL: https://api.core.today/v1
Create Prediction: POST /predictions
Get Status: GET /predictions/{job_id}

## Authentication
Header: X-API-Key: YOUR_API_KEY

## Input Parameters

### Required
- **prompt**: string - Text prompt describing the video. Be specific about subject, motion, camera movement, lighting, and pacing.

### Optional
- **aspect_ratio**: string (default: 16:9) - Aspect ratio of the generated video. Ignored when start_image or end_image is set — the model derives the ratio from the anchor frame(s).
  Options: 9:16, 3:4, 1:1, 4:3, 16:9, 21:9
- **resolution**: string (default: 720p) - Output resolution. 540p is not available when hdr is true.
  Options: 540p, 720p, 1080p
- **duration**: integer (default: 5) - Video duration in seconds. 10s is not supported with hdr, start_image, end_image, or loop.
  Options: 5, 10
- **hdr**: boolean (default: false) - Generate HDR-encoded MP4. Requires 720p or 1080p, 5s duration, and no loop.
- **exr_export**: boolean (default: false) - Export an EXR file alongside the MP4 for professional colour-grading workflows. Requires hdr=true.
- **loop**: boolean (default: false) - Generate a seamlessly looping video. Not supported with 10s duration, hdr, or end_image.
- **start_image**: string - Optional first frame of the video. Only valid with 5s duration.
- **end_image**: string - Optional last frame of the video. Only valid with 5s duration; not supported with loop.

## Examples

### Cinematic HDR text-to-video
Generate a 5-second HDR clip for a color-grading pipeline.
```json
{
  "model": "luma/ray-3.2",
  "input": {
    "prompt": "A slow aerial pull-back over a misty mountain valley at sunrise, warm golden light breaking through the clouds.",
    "resolution": "1080p",
    "duration": 5,
    "hdr": true,
    "exr_export": true
  }
}
```

### Keyframe transition between two shots
Anchor a video with a start and end image to control the exact first and last frame.
```json
{
  "model": "luma/ray-3.2",
  "input": {
    "prompt": "Smooth camera dolly transitioning from the empty street to the crowded market.",
    "start_image": "https://example.com/street-empty.jpg",
    "end_image": "https://example.com/street-crowded.jpg",
    "duration": 5
  }
}
```

## Response Format
```json
{
  "job_id": "abc123",
  "status": "pending | processing | completed | failed",
  "result": "URL or data (when completed)"
}
```

## Usage Flow
1. POST /predictions with model and input -> receive job_id
2. GET /predictions/{job_id} -> poll until status is completed or failed
3. Result contains output URL(s)

## Tips
- hdr requires 720p or 1080p, a 5-second duration, and loop disabled — 10-second clips and 540p aren't compatible with HDR.
- exr_export only works when hdr is true; use it when you need to hand footage to a professional color-grading pipeline.
- When start_image or end_image is set, aspect_ratio is ignored — the ratio comes from the anchor image(s) instead.
- 10-second duration can't be combined with hdr, start_image, end_image, or loop — pick 5s if you need any of those features.

## Documentation
https://replicate.com/luma/ray-3.2