Background Replace

Replace the background of an image with a solid color or gradient. The AI model detects the subject, removes the original background, and composites the subject onto your chosen background.

API Endpoint

POST /api/v1/tools/background-replace

Accepts multipart form data with an image file and a JSON settings field.

Parameters

Parameter	Type	Required	Default	Description
backgroundType	string	No	"color"	Background mode: color or gradient
color	string	No	"#ffffff"	Background hex color (when backgroundType is color)
gradientColor1	string	No	-	First gradient hex color
gradientColor2	string	No	-	Second gradient hex color
gradientAngle	integer	No	180	Gradient angle in degrees (0-360)
feather	integer	No	0	Edge feathering radius (0-20)
format	string	No	"png"	Output format: png or webp

Example Request

curl -X POST http://localhost:1349/api/v1/tools/background-replace \
  -H "Authorization: Bearer si_your-api-key" \
  -F "[email protected]" \
  -F 'settings={"backgroundType": "color", "color": "#2563eb", "feather": 2}'

Example Response

{
  "jobId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "async": true
}

Track progress via SSE at GET /api/v1/jobs/{jobId}/progress. When the job completes, the SSE stream emits a completed event with the download URL.

Notes

• This is an AI-powered tool that returns 202 Accepted and processes asynchronously. Connect to the SSE endpoint to receive progress updates and the final result.
• Requires the background-removal feature bundle to be installed. Returns 501 if the bundle is not available.
• HEIC, RAW, PSD, and SVG inputs are automatically decoded before processing.
• Output defaults to PNG to preserve transparency around the subject.