xtract.bot

POST /api/ocr-prep-id-card10 quota units per call · cache hits free

Pre-process a passport, drivers licence, or other ID card photo: detect the card edges, crop, deskew, and normalise lighting for clean OCR.

Specialised pre-processing for photos of identity documents — passports, driving licences, national IDs, library cards. The pipeline detects the card outline, crops to its bounds, corrects perspective so the card is rectangular, and normalises lighting so the resulting image is OCR-friendly. Glare patches and shadows are reduced where possible. Output is a clean rectangular PNG ready for `document-ocr`. Pair the two for an end-to-end ID-photo → text pipeline.

Inputs

NameTypeDefaultDescription
image*filePhoto of an ID card / passport / driver's license.
granularityenum (text | word | line | word+line)"text"OCR detail level.
returnPrepImagebooleanfalseReturn the prep'd PNG as base64.

Response

Modes: json. Cache: yes (24h TTL).

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 call10 units against the 10,000-unit monthly quota. Cache hits are free — only cache misses decrement.
Burst limit200 requests per rolling minute, shared across all tools.
Max request size25 MiB (base64 inflates file payloads ~33% — the limit applies to the decoded bytes).
Max response size30 MiB
Timeout90s wall clock.
Rate-limit headersX-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).

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

Code samples

Built from the sample example.

# Download or substitute the example input:
#   curl -O https://xtract.bot/examples/ocr-fixtures/document-small.png
IMAGE=$(base64 -w0 < document-small.png)

curl -X POST https://api.xtract.bot/api/ocr-prep-id-card \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -H "X-Account-Id: $XTRACT_ACCOUNT_ID" \
  -H "X-Api-Key: $XTRACT_API_KEY" \
  -d '{
  "image": "'"$IMAGE"'"
}'