README.md

v1.face-swap

Module Functions

Face Swap Generate Workflow

The workflow performs the following action

1. upload local assets to Magic Hour storage. So you can pass in a local path instead of having to upload files yourself
2. trigger a generation
3. poll for a completion status. This is configurable
4. if success, download the output to local directory

Tip

This is the recommended way to use the SDK unless you have specific needs where it is necessary to split up the actions.

Parameters

In addition to the parameters listed in the create section below, generate introduces 3 new parameters:

• waitForCompletion (boolean, default true): Whether to wait for the project to complete.
• downloadOutputs (boolean, default true): Whether to download the generated files
• downloadDirectory (string, optional): Directory to save downloaded files (defaults to current directory)

Example Snippet

import { Client } from "magic-hour";

const client = new Client({ token: process.env["API_TOKEN"]!! });
const res = await client.v1.faceSwap.generate(
  {
    assets: {
      faceMappings: [
        {
          newFace: "api-assets/id/1234.png",
          originalFace: "api-assets/id/0-0.png",
        },
      ],
      faceSwapMode: "all-faces",
      imageFilePath: "image/id/1234.png",
      videoFilePath: "/path/to/1234.mp4",
      videoSource: "file",
    },
    endSeconds: 15.0,
    name: "Face Swap video",
    startSeconds: 0.0,
    style: { version: "default" },
  },
  {
    waitForCompletion: true,
    downloadOutputs: true,
    downloadDirectory: ".",
  },
);

Face Swap Video

What this API does

Create the same Face Swap you can make in the browser, but programmatically, so you can automate it, run it at scale, or connect it to your own app or workflow.

Good for

• Automation and batch processing
• Adding face swap into apps, pipelines, or tools

How it works (3 steps)

1. Upload your inputs (video, image, or audio) with Generate Upload URLs and copy the file_path.
2. Send a request to create a face swap job with the basic fields.
3. Check the job status until it's complete, then download the result from downloads.

Key options

• Inputs: usually a file, sometimes a YouTube link, depending on project type
• Resolution: free users are limited to 576px; higher plans unlock HD and larger sizes
• Extra fields: e.g. face_swap_mode, start_seconds/end_seconds, or a text prompt

Cost
Credits are only charged for the frames that actually render. You'll see an estimate when the job is queued, and the final total after it's done.

For detailed examples, see the product page.

API Endpoint: POST /v1/face-swap

Parameters

Parameter	Required	Deprecated	Description	Example
assets	✓	✗	Provide the assets for face swap. For video, The video_source field determines whether video_file_path or youtube_url field is used	{"faceMappings": [{"newFace": "api-assets/id/1234.png", "originalFace": "api-assets/id/0-0.png"}], "faceSwapMode": "all-faces", "imageFilePath": "image/id/1234.png", "videoFilePath": "api-assets/id/1234.mp4", "videoSource": "file"}
└─ faceMappings	✗	—	This is the array of face mappings used for multiple face swap. The value is required if face_swap_mode is individual-faces.	[{"newFace": "api-assets/id/1234.png", "originalFace": "api-assets/id/0-0.png"}]
└─ faceSwapMode	✗	—	Choose how to swap faces: all-faces (recommended) — swap all detected faces using one source image (source_file_path required) +- individual-faces — specify exact mappings using face_mappings	"all-faces"
└─ imageFilePath	✗	—	The path of the input image with the face to be swapped. The value is required if face_swap_mode is all-faces. This value is either - a direct URL to the video file - file_path field from the response of the upload urls API. See the file upload guide for details.	"image/id/1234.png"
└─ videoFilePath	✗	—	Your video file. Required if video_source is file. This value is either - a direct URL to the video file - file_path field from the response of the upload urls API. See the file upload guide for details.	"api-assets/id/1234.mp4"
└─ videoSource	✓	—	Choose your video source.	"file"
└─ youtubeUrl	✗	—	YouTube URL (required if video_source is youtube).	"http://www.example.com"
endSeconds	✓	✗	End time of your clip (seconds). Must be greater than start_seconds.	15.0
startSeconds	✓	✗	Start time of your clip (seconds). Must be ≥ 0.	0.0
height	✗	✓	height is deprecated and no longer influences the output video's resolution. This field is retained only for backward compatibility and will be removed in a future release.	123
name	✗	✗	Give your video a custom name for easy identification.	"My Face Swap video"
style	✗	✗	Style of the face swap video.	{"version": "default"}
└─ version	✗	—	* v1 - May preserve skin detail and texture better, but weaker identity preservation. * v2 - Faster, sharper, better handling of hair and glasses. stronger identity preservation. * default - Use the version we recommend, which will change over time. This is recommended unless you need a specific earlier version. This is the default behavior.	"default"
width	✗	✓	width is deprecated and no longer influences the output video's resolution. This field is retained only for backward compatibility and will be removed in a future release.	123

Example Snippet

import { Client } from "magic-hour";

const client = new Client({ token: process.env["API_TOKEN"]!! });
const res = await client.v1.faceSwap.create({
  assets: {
    faceMappings: [
      {
        newFace: "api-assets/id/1234.png",
        originalFace: "api-assets/id/0-0.png",
      },
    ],
    faceSwapMode: "all-faces",
    imageFilePath: "image/id/1234.png",
    videoFilePath: "api-assets/id/1234.mp4",
    videoSource: "file",
  },
  endSeconds: 15.0,
  name: "My Face Swap video",
  startSeconds: 0.0,
  style: { version: "default" },
});

Response

Type

V1FaceSwapCreateResponse

Example

{"creditsCharged": 450, "estimatedFrameCost": 450, "id": "cuid-example"}