Titanium - URL Screenshot & Animation Service

A web service that captures screenshots and animated recordings of web pages using headless Chromium. Simple HTTP API, runs in Docker/k8s without GPU.

API

Render URL to PNG

GET /render.png?url={base64_url}&w={width}&h={height}[&cache={ttl}][&verify={sig}]

Render URL to Animated PNG (APNG)

GET /render.apng?url={base64_url}&w={width}&h={height}[&duration={secs}][&fps={fps}][&cache={ttl}][&verify={sig}]

Parameters

Param	Required	Default	Description
url	yes	-	URL-safe base64-encoded URL
w	yes	-	Viewport width in pixels
h	yes	-	Viewport height in pixels
duration	no	3	Animation duration in seconds (max 10, APNG only)
fps	no	10	Frames per second (max 30, APNG only)
cache	no	-	Cache TTL in seconds. Serves cached result if available
verify	no	-	HMAC-SHA256 signature (required when SIGNING_KEY is set)

Health Check

GET /health

Examples

# Screenshot of example.com
URL=$(echo -n "https://example.com" | base64 -w0)
curl "http://localhost:3000/render.png?url=$URL&w=800&h=600" > screenshot.png

# Animated capture of a page (3 seconds, 10 fps)
curl "http://localhost:3000/render.apng?url=$URL&w=800&h=600&duration=3&fps=10" > animation.apng

# With caching (5 minute TTL)
curl "http://localhost:3000/render.png?url=$URL&w=800&h=600&cache=300" > cached.png

Request Signing

Set SIGNING_KEY to require HMAC-SHA256 signatures on all render requests.

The signature is computed over the canonical query string: all params except verify, sorted alphabetically, joined with &.

# Generate signature
CANONICAL="h=600&url=${URL}&w=800"
SIG=$(echo -n "$CANONICAL" | openssl dgst -sha256 -hmac "your-secret" | cut -d' ' -f2)

curl "http://localhost:3000/render.png?url=$URL&w=800&h=600&verify=$SIG"

Running

Docker (recommended)

docker-compose up -d

Local

Requires Chromium/Chrome installed on the host.

cargo build --release
SIGNING_KEY=optional-secret ./target/release/titanium

Server starts on http://localhost:3000.

Environment Variables

Variable	Description
SIGNING_KEY	HMAC-SHA256 key for request verification. Omit to disable signing.
RUST_LOG	Log level (e.g. titanium=info)

Architecture

• Rust with Axum for the HTTP server
• Chromium (headless) via chromiumoxide for rendering
• Full CSS, JavaScript, and font support
• Single persistent browser instance, one tab per request
• APNG animation captures multiple frames with configurable timing
• File-based caching with TTL expiry in /tmp/

License

MIT