Text Overlay

Add styled text to images with optional drop shadow and semi-transparent background box. Suitable for titles, captions, or annotations on photos.

API Endpoint

POST /api/v1/tools/text-overlay

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

Parameters

Parameter	Type	Required	Default	Description
text	string	Yes	-	Text to overlay (1 to 500 characters)
fontSize	number	No	48	Font size in pixels (8 to 200)
color	string	No	"#FFFFFF"	Text color in hex format (#RRGGBB)
position	string	No	"bottom"	Vertical placement: top, center, bottom
backgroundBox	boolean	No	false	Show a semi-transparent background rectangle behind the text
backgroundColor	string	No	"#000000"	Background box color in hex format (#RRGGBB)
shadow	boolean	No	true	Apply a drop shadow behind the text

Example Request

curl -X POST http://localhost:1349/api/v1/tools/text-overlay \
  -H "Authorization: Bearer si_your-api-key" \
  -F "[email protected]" \
  -F 'settings={"text": "Hello World", "fontSize": 64, "color": "#FFFFFF", "position": "bottom", "shadow": true}'

With a background box:

curl -X POST http://localhost:1349/api/v1/tools/text-overlay \
  -H "Authorization: Bearer si_your-api-key" \
  -F "[email protected]" \
  -F 'settings={"text": "Caption", "fontSize": 36, "position": "bottom", "backgroundBox": true, "backgroundColor": "#000000"}'

Example Response

{
  "jobId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "downloadUrl": "/api/v1/download/a1b2c3d4-e5f6-7890-abcd-ef1234567890/photo.jpg",
  "originalSize": 2450000,
  "processedSize": 2470000
}

Notes

• Text is always centered horizontally within the image.
• The drop shadow uses a 2px offset with 3px blur at 70% black opacity.
• The background box spans the full image width at 70% opacity, with height proportional to the font size (1.8x).
• Text is rendered via SVG composite, so the system's default sans-serif font is used.
• XML-special characters in the text are safely escaped.
• Output format matches the input format. HEIC, RAW, PSD, and SVG inputs are automatically decoded before processing.