Documentation

Images API

The Images API allows you to serve and transform images on-the-fly. You can resize, crop, apply effects, and optimize images for different use cases.

Serve Image

Access and serve an image, with optional transformations applied on-the-fly.

Endpoint

bash

GET /file/:path

Path Parameters

Parameter	Type	Description
path	String	The path to the image file

Query Parameters

Parameter	Type	Description
w	Integer	Width in pixels (1-5000)
h	Integer	Height in pixels (1-5000)
fit	String	Resize mode: cover, contain, fill, inside, outside
q	Integer	Quality (1-100)
blur	Number	Blur radius (0.3-1000)
sharp	Boolean	Apply sharpening
gray	Boolean	Convert to grayscale
rot	Integer	Rotation angle (-360 to 360)
border	String	Format: 'width_hexcolor' (e.g., '5_FF0000')
crop	String	Format: 'x,y,width,height'

Example Request

bash

curl https://api.getpronto.io/v1/file/image.jpg?w=800&h=600&fit=cover&q=90 \
  -H "ApiKey: YOUR_API_KEY"

The response will be the image data with appropriate content-type headers.

Generate Transform URL

Generate a URL for an image with specified transformations.

Endpoint

bash

POST /file/:id/transform-url

Path Parameters

Parameter	Type	Description
id	String	The unique identifier of the image

Request Body Parameters

Parameter	Type	Description
w	Integer	Width in pixels (1-5000)
h	Integer	Height in pixels (1-5000)
fit	String	Resize mode: cover, contain, fill, inside, outside
q	Integer	Quality (1-100)
blur	Number	Blur radius (0.3-1000)
sharp	Boolean	Apply sharpening
gray	Boolean	Convert to grayscale
rot	Integer	Rotation angle (-360 to 360)
border	String	Format: 'width_hexcolor' (e.g., '5_FF0000')
crop	String	Format: 'x,y,width,height'
format	String	Output format (jpg, png, webp, etc)

Example Request

bash

curl -X POST https://api.getpronto.io/v1/file/123e4567-e89b-12d3-a456-426614174000/transform-url \
  -H "ApiKey: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "w": 800,
    "h": 600,
    "fit": "cover",
    "q": 90,
    "format": "webp"
  }'

Response

json

{
  "url": "https://api.getpronto.io/v1/file/image.webp?w=800&h=600&fit=cover&q=90",
  "originalFile": {
    "id": "123e4567-e89b-12d3-a456-426614174000",
    "filename": "image.jpg",
    "mimetype": "image/jpeg"
  },
  "transformations": {
    "w": 800,
    "h": 600,
    "fit": "cover",
    "q": 90,
    "format": "webp"
  }
}

Transformation Options

The following transformations can be applied to images either via URL parameters or through the transform URL endpoint:

Resize

Parameter	Type	Description
w, h	Integer	Target dimensions (1-5000px)
fit	String	How image fits: cover (default), contain, fill, inside, outside

Example: w=800&h=600&fit=cover

Quality

Parameter	Type	Description
q	Integer	JPEG/WebP quality (1-100)

Example: q=90

Effects

Parameter	Type	Description
blur	Number	Gaussian blur (0.3-1000)
sharp	Boolean	Sharpen the image
gray	Boolean	Convert to grayscale

Example: blur=5&sharp=true&gray=true

Rotation & Cropping

Parameter	Type	Description
rot	Integer	Rotation angle (-360 to 360)
crop	String	Crop coordinates (x,y,width,height)

Example: rot=90&crop=100,100,500,500

Note: Transformations are processed in the order they are specified. For example, if you apply both crop and resize, the image will be cropped first, then resized to the specified dimensions.

Next Steps

Continue exploring our documentation with these related topics:

SDK Image Operations

Use our SDK for easy image transformations

Supported File Formats

Learn about supported image formats

Files API

Manage your image files and assets