Image inpaint

POST /api/image-inpaint5 quota units per call · cache hits free

Remove text, scratches, watermarks or small objects from a photo. Provide a mask marking the pixels to remove and OpenCV's inpaint algorithm fills them in from the surrounding area.

Fills a masked region with content inferred from the surrounding pixels — OpenCV's `cv.inpaint`. Useful for: - Removing dust / scratches from a scanned photo. - Erasing small unwanted objects (signs, dates, watermarks). - Filling holes in a corrupted scan. Inputs: - `image`: source image bytes. - `mask`: same-resolution single-channel image where **white** (255) marks pixels to inpaint and **black** (0) marks pixels to keep. PNG with grayscale or alpha-channel input both work. - `radius`: how far each masked pixel looks for neighbours (px). - `method`: `telea` (fast marching, sharper edges) or `ns` (Navier-Stokes, smoother results on large holes). **Limitations:** Classical inpaint can't hallucinate content — it diffuses surrounding texture inwards. For large holes or structured fills (e.g. removing a face) you need a generative model (out of scope here).

Inputs

Name	Type	Default	Description
image*	file	—	Source image bytes.
mask*	file	—	Inpaint mask — same resolution as `image`. White (255) = inpaint; black (0) = keep.
radius	number (1…30)	3	Inpaint radius in pixels. Larger = smoother fill, slower.
method	enum (telea \| ns)	"telea"	Algorithm. `telea` = fast marching (sharper, faster). `ns` = Navier-Stokes (smoother on large holes).
format	enum (png \| jpeg)	"png"	Output image format.

Response

Modes: binary, stream, json. Cache: yes (24h TTL).

Large outputs stream: responses over the 4 MiB cache limit are piped through as they are produced instead of buffered. They carry x-cache-skip: size and are never cached — identical follow-up calls recompute.

Every response carries x-cache (HIT / MISS / BYPASS), x-cache-signature (stable across identical inputs), and the rate-limit headers listed below.

Quota & limits

Cost per call	5 units against the 10,000-unit monthly quota. Cache hits are free — only cache misses decrement.
Burst limit	200 requests per rolling minute, shared across all tools.
Max request size	`15 MiB` (base64 inflates file payloads ~33% — the limit applies to the decoded bytes).
Max response size	`25 MiB`
Timeout	30s wall clock.
Rate-limit headers	`X-RateLimit-Limit`, `X-RateLimit-Remaining`, `X-RateLimit-Burst-Limit` on every response; `X-Quota-Warning` once 80% of the monthly quota is spent; `Retry-After` on 429s.

Errors

Errors are JSON with an error string; schema failures add a details object (Zod's flattened field errors).

Status	When	Body
400	Input fails the tool's schema (wrong type, missing required field, malformed base64) or the file bytes can't be parsed as the expected format.	{ "error": "invalid inputs", "details": { "fieldErrors": { … } } }
401	Missing or invalid X-Api-Key / X-Account-Id headers (or no session when called from the browser).	{ "error": "unauthorized" }
404	Unknown tool id, or calling /api/* on the website hostname instead of api.xtract.bot.	{ "error": "not found" }
413	Request body over the tool's max request size, or an image header declaring more megapixels than the tool's pixel budget.	{ "error": "…exceeds maxRequestBytes…" }
415	Content-Type isn't application/json on the json-body transport.	{ "error": "unsupported content-type; expected application/json" }
429	Monthly quota or the 200/min burst limit exhausted. Check Retry-After and the X-RateLimit-* headers.	{ "error": "monthly quota exceeded", "monthRemaining": 0, … }
5xx	Conversion engine failure. Safe to retry; if it persists, the input is hitting a bug — please report it.	{ "error": "…" }

Code samples

Built from the telea-circle example.

# Download or substitute the example input:
#   curl -O https://xtract.bot/examples/image-inpaint/sample.png
IMAGE=$(base64 -w0 < sample.png)
# Download or substitute the example input:
#   curl -O https://xtract.bot/examples/image-inpaint/mask.png
MASK=$(base64 -w0 < mask.png)

curl -X POST https://api.xtract.bot/api/image-inpaint \
  -H "Content-Type: application/json" \
  -H "Accept: application/octet-stream" \
  -H "X-Account-Id: $XTRACT_ACCOUNT_ID" \
  -H "X-Api-Key: $XTRACT_API_KEY" \
  -d '{
  "image": "'"$IMAGE"'",
  "mask": "'"$MASK"'"
}'