▣ MODEL KIT · MEDIA KIT

Generate Image Foreground Mask API

What it does

The Image Mask API finds the main subject in an image and returns a grayscale mask of it. Use the mask to composite, clean up edges or analyse the subject in your own pipeline.

Send the image in image, as a public URL or base64 data, up to 20 MB. Set format to json (default) or png. JSON returns the mask as a data URI with its metadata. PNG returns the mask file. Set quality to best (default) or fast. Set crop to true to trim the mask to the subject, with padding (0 to 1000 pixels) of space around it. Use max_size to limit the output size.

The JSON response includes the width, height, bytes, the subject bbox in the original image and the foreground_ratio, the share of the image covered by the subject. If no subject is found, bbox is null.

Teams use the Image Mask API to build cutouts for product photos and to place subjects on new backgrounds in their own editor. Others check that an upload has a clear subject, or crop images to it.

To get the cut-out subject instead of the mask, use the Remove Image Background with Advanced Controls API. To read text from images, use the Image & PDF OCR to Markdown API.

POST

Get the subject mask

https://api.eu.apyhub.com/callable-labs/foreground-mask/v1/background/mask

QUICKSTART

GUIDE

Quickstart

Send a public image URL to remove its background and return mask metadata in JSON.

curl -X POST "https://api.eu.apyhub.com/callable-labs/foreground-mask/v1/background/mask" \
  -H "apy-token: $APY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "image": {
      "url": "https://assets.apyhub.com/samples/cat.jpg"
    }
  }'

What you'll get back

Returns a JSON object with these top-level fields: format and media_type are strings, width and height are output dimensions in pixels, bytes is the payload size, data_uri is a data:<media_type>;base64,... string, bbox is either an object with x, y, width, and height or null, foreground_ratio is a number between 0 and 1, and quality is "best" or "fast".

{
  "format": "json",
  "media_type": "image/png",
  "width": 800,
  "height": 600,
  "bytes": 124532,
  "data_uri": "data:image/png;base64,iVBORw0KGgoAAA...",
  "bbox": { "x": 120, "y": 45, "width": 540, "height": 510 },
  "foreground_ratio": 0.42,
  "quality": "best"
}

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About this endpoint

What it does

Generates a subject mask for an input image. The request accepts an image source and optional output controls, and the response returns mask metadata plus either a data URI or PNG-oriented output depending on the requested format.

Request Body

Parameter	Type	Description
crop	Boolean	Crop the result to the subject's bounding box. Default: `false`.
image	Object	Image source object. Contains `url` and/or `base64`; see nested fields.
image.url	String	Public http(s) URL of the image. Must be ≤ 20 MB; private and internal addresses are refused.
image.base64	String	The image as base64, including a `data:` URI if desired. Must be ≤ 20 MB decoded.
format	ENUM	Output format. Allowed values: `json`, `png`. Default: `json`. `json` returns metadata plus a PNG data URI; `png` returns the 8-bit grayscale mask.
padding	Integer	Pixels kept around the subject when `crop` is true. Default: `0`; minimum: `0`, maximum: `1000`.
quality	ENUM	Output quality. Allowed values: `best`, `fast`. Default: `best`. `best` prioritizes detail; `fast` is suitable for previews.
max_size	Integer	Longest side of the output in pixels. Default: original size; minimum: `64`, maximum: `4096`.

Response

Returns a JSON object with format, media_type, width, height, bytes, data_uri, bbox, foreground_ratio, and quality fields. bbox is either an object with x, y, width, and height, or null when nothing was found.

Parameter	Type	Description
bbox	Object	Subject bounding box in the original image, or `null` when nothing was found.
bbox.x	Integer	X coordinate of the bounding box.
bbox.y	Integer	Y coordinate of the bounding box.
bbox.width	Integer	Width of the bounding box.
bbox.height	Integer	Height of the bounding box.
bytes	Integer	Size of the output in bytes.
width	Integer	Output width in pixels.
format	String	Encoding of `data_uri`.
height	Integer	Output height in pixels.
quality	ENUM	Quality used for the result. Allowed values: `best`, `fast`.
data_uri	String	`data:<media_type>;base64,…`
media_type	String	Media type of the returned data URI.
foreground_ratio	Number	Share of the original image covered by the subject, from `0` to `1`.

▣ COMMON ERRORS

Errors any endpoint can return

400bad_request

Required parameter missing or malformed body.

401unauthorized

API key missing, revoked, or not authorized for this service.

429rate_limited

Your plan's per-second rate exceeded. Retry with exponential backoff.

503upstream_busy

Backend temporarily unavailable. Try again in a few seconds.

Similar APIs

Closest matches in the catalog based on this service.

CALLRemove Image Background with Advanced Controls APICallable Labs CALLChange Background of Images APIApyHub CALLRemove Background from Images APIApyHub CALLCompress Images APIApyHub

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