GIF → animated PNG (APNG)

POST /api/gif-to-apng2 quota units per call · cache hits free

Convert an animated GIF to an animated PNG (APNG). Preserves every frame and its delay. APNGs are backwards compatible — viewers that don't understand the animation chunks just show the first frame.

Re-encodes an animated GIF as an animated PNG (APNG). Every frame is composited (handling GIF's disposal modes), encoded losslessly, and packed into a standard APNG file. APNGs are a strict superset of PNG — a viewer that doesn't know about animation just sees the first frame, so the output works as a fallback PNG too. Compared to animated WebP, APNGs are larger but render correctly in older browsers and image viewers.

Inputs

Name	Type	Default	Description
gif*	file	—	Input animated GIF.

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	2 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	`25 MiB` (base64 inflates file payloads ~33% — the limit applies to the decoded bytes).
Max response size	`100 MiB`
Timeout	60s 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 dog-bounding example.

# Download or substitute the example input:
#   curl -O https://xtract.bot/examples/gif-extract-frames/dog-bounding.gif
GIF=$(base64 -w0 < dog-bounding.gif)

curl -X POST https://api.xtract.bot/api/gif-to-apng \
  -H "Content-Type: application/json" \
  -H "Accept: application/octet-stream" \
  -H "X-Account-Id: $XTRACT_ACCOUNT_ID" \
  -H "X-Api-Key: $XTRACT_API_KEY" \
  -d '{
  "gif": "'"$GIF"'"
}'