> ## Documentation Index
> Fetch the complete documentation index at: https://docs.viggle.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Transparent output

> Create alpha output for video compositing.

Set `background_mode` to `transparent` to create a main video and an alpha mask for compositing.

```bash theme={null}
curl -X POST "https://apis.viggle.ai/v1/renders" \
  -H "Authorization: Bearer $VIGGLE_API_KEY" \
  -F "image=@character.png" \
  -F "motion_video=@motion.mp4" \
  -F "background_mode=transparent"
```

When the Render is ready, the response contains:

```json theme={null}
{
  "status": "ready",
  "video_url": "https://...",
  "alpha_url": "https://..."
}
```

Use `video_url` as the foreground video and `alpha_url` as its mask in your editor. For a green-screen workflow, use `background_mode=solid` and set `bg_color` to `0,255,0`.