Shrinkray is a lightweight, high-performance image proxy written in Rust.
- On-the-fly resizing, cropping and format conversion
- Configurable routing for file, HTTP or S3 backends
- Optional HMAC signatures to secure image URLs
- Prometheus metrics and OpenTelemetry tracing
- Offload image resizing logic from your app server
- Serve responsive images without storing multiple variants
- Optimize external images at request time
- Use as a backend to a CDN for on-demand image transformation
Shrinkray draws inspiration from other great image processing services, including:
- dali β a flexible image server
- imgproxy β a high-performance Golang image proxy
- imgix β a commercial image optimization platform
Download and edit the Kubernetes config file:
curl -O https://raw.githubusercontent.com/tpyo/shrinkray/refs/heads/main/kubernetes/config.yamlApply the Kubernetes manifests:
kubectl apply -f config.yaml
kubectl apply -f https://raw.githubusercontent.com/tpyo/shrinkray/refs/heads/main/kubernetes/deployment.yamlRun docker-compose up to start a development instance listening on http://localhost:9000.
Grafana is available at http://localhost:3000.
http://localhost:9000/samples/02.jpg?w=400&h=400&dpr=2&fit=crop
- Resizes to 800Γ800 at double device pixel ratio (for retina screens)
- Fits by cropping to fill the dimensions
http://localhost:9000/samples/04.jpg?w=1024&h=768
- Fits within 1024Γ768 without cropping
http://localhost:9000/samples/03.jpg?ar=4:3&w=400
- Resizes to 400x300 with cropping
http://localhost:9000/samples/trim.jpg?trim=auto
- Trim colour can be set with
trim=colourandtrim-colour=ffffff
http://localhost:9000/samples/01.jpg?rot=180
http://localhost:9000/samples/08.jpg?monochrome=100
http://localhost:9000/samples/08.jpg?duotone=003263,ffa600
http://localhost:9000/samples/08.jpg?duotone=003263,ffa600&duotone-alpha=50
- Applies duotone effect at 50% opacity, blending with original image
http://localhost:9000/samples/08.jpg?tint=ff0000
- Applies a red color tint to the image
http://localhost:9000/samples/08.jpg?blur=100
| Parameter | Description |
|---|---|
w |
Width in pixels |
h |
Height in pixels |
bg |
Background colour used when padding or flattening |
ar |
Aspect ratio (e.g. 16:9) |
q |
Output quality (default: 75) |
dpr |
Device pixel ratio multiplier |
rot |
Rotation in degrees (90, 180 or 270) |
fit |
Resizing mode (clip, crop, max) (default: clip) |
fm |
Output format (jpeg, webp, png, avif) |
dl |
Download filename for the response |
lossless |
Enable lossless encoding when available |
trim |
Trim borders automatically (auto, colour) |
trim-colour |
Set the trim colour for the trim parameter |
sharpen |
Adjust sharpness (0-100) |
blur |
Apply a blur (0-100) |
tint |
Apply a colour tint (e.g; ff0000) |
kodachrome |
Filter application (0-100) |
vintage |
Filter application (0-100) |
polaroid |
Filter application (0-100) |
technicolor |
Filter application (0-100) |
sepia |
Filter application (0-100) |
monochrome |
Filter application (0-100) |
duotone |
Duotone (shadow,highlight - e.g; 003263,ffa600) |
duotone-alpha |
Duotone opacity/alpha (1-100) (default: 100) |
sig |
HMAC signature used by sign() for request verification |
- http://localhost:9001/metrics - Prometheus metrics endpoint
- http://localhost:9001/healthz - Health endpoint
Shrinkray exports the following Prometheus metrics:
| Metric | Description |
|---|---|
shrinkray_http_response_200_count |
Count of successful responses |
shrinkray_http_response_401_count |
Count of unauthorized responses |
shrinkray_http_response_404_count |
Count of not found responses |
shrinkray_http_response_500_count |
Count of internal server errors |
| Metric | Labels | Description |
|---|---|---|
shrinkray_fetch_duration_seconds |
backend |
Duration of image fetching operations |
shrinkray_output_duration_seconds |
format |
Duration of image encoding operations |
Both histogram metrics use buckets: 0.005, 0.01, 0.025, 0.05, 0.075, 0.1, 0.25, 0.5, 0.75, 1.0, 2.5, 5.0, 10.0 seconds.