slimg 0.5.1

Fast image optimization library powered by Rust

slimg

Python bindings for the slimg image optimization library.

Supports macOS (Apple Silicon, Intel), Linux (x86_64, ARM64), and Windows (x86_64) -- native extensions are bundled in pre-built wheels.

Installation

pip install slimg

Usage

import slimg

# Open an image file
image = slimg.open("photo.jpg")
print(f"{image.width}x{image.height} {image.format}")

# Convert to WebP
result = slimg.convert(image, format="webp", quality=80)
result.save("photo.webp")

# Optimize in the same format
result = slimg.optimize_file("photo.jpg", quality=75)
result.save("optimized.jpg")

# Resize by width (preserves aspect ratio)
resized = slimg.resize(image, width=800)
result = slimg.convert(resized, format="png")
result.save("thumbnail.png")

# Crop to aspect ratio (centre-anchored)
cropped = slimg.crop(image, aspect_ratio=(16, 9))

# Crop by pixel region
cropped = slimg.crop(image, region=(100, 50, 800, 600))

# Extend (pad) to aspect ratio with a fill colour
extended = slimg.extend(image, aspect_ratio=(1, 1), fill=(255, 255, 255))

# Extend with transparent padding (default)
extended = slimg.extend(image, aspect_ratio=(1, 1))

Supported Formats

Format	Decode	Encode	Notes
JPEG	Yes	Yes	MozJPEG encoder
PNG	Yes	Yes	OxiPNG + Zopfli compression
WebP	Yes	Yes	Lossy encoding via libwebp
AVIF	Yes	Yes	ravif encoder; dav1d decoder
QOI	Yes	Yes	Lossless, fast encode/decode
JPEG XL	Yes	No	Decode-only

API Reference

Functions

Function	Description
open(path)	Decode an image file from disk
decode(data)	Decode image bytes (auto-detects format)
convert(image, format, quality=80)	Encode image in a target format
resize(image, *, width/height/exact/fit/scale)	Resize an image
crop(image, *, region/aspect_ratio)	Crop an image
extend(image, *, aspect_ratio/size, fill)	Pad an image canvas
optimize(data, quality=80)	Re-encode bytes to reduce file size
optimize_file(path, quality=80)	Read a file and re-encode

Types

Type	Description
Format	JPEG, PNG, WEBP, AVIF, JXL, QOI
Image	Decoded image with width, height, data, format
Result	Encoded output with data, format, and save(path)
Resize	Factory: width, height, exact, fit, scale
Crop	Factory: region, aspect_ratio
Extend	Factory: aspect_ratio, size
SlimgError	Error with subclasses: UnsupportedFormat, UnknownFormat, EncodingNotSupported, Decode, Encode, Resize, Crop, Extend, Io, Image

Supported Platforms

Platform	Architecture	Status
macOS	Apple Silicon (aarch64)	Supported
macOS	Intel (x86_64)	Supported
Linux	x86_64	Supported
Linux	ARM64 (aarch64)	Supported
Windows	x86_64	Supported

Requirements

• Python 3.9+

License

MIT