Swevo.AutoImage 1.1.0

AutoImage

Free, MIT-licensed fluent image processing for .NET. No revenue threshold, no commercial license — ever.

Why AutoImage?

ImageSharp is licensed under the Six Labors Split License: free for individuals, open source projects, and companies under $1M annual revenue — everyone else needs a paid commercial license, with no exemption for public-sector or non-profit organizations above that threshold. AutoImage wraps SkiaSharp (MIT licensed, Google's Skia graphics engine) behind a small, fluent, ImageSharp-like API for the operations most apps actually need, fully free for everyone regardless of revenue.

What AutoImage actually is

AutoImage is a thin fluent wrapper. It contains no image codec, resampling, or compositing logic of its own — every decode, resize, crop, and encode is performed by SkiaSharp. AutoImage only provides a small, chainable surface over it:

• Load a file path or stream
• Resize with Stretch, Fit (letterbox, preserves aspect ratio), or Cover (crop-to-fill, like CSS background-size: cover)
• Crop to an explicit rectangle
• Rotate90 in 90-degree increments
• Basic filters: Grayscale, Blur, Sharpen, Brightness, Contrast, Saturate
• Text and image watermarks
• Save to a file or ToBytes in memory, encoding to Png, Jpeg, Webp, Bmp, or Gif

What AutoImage explicitly does NOT do

Arbitrary-angle rotation and advanced multi-layer compositing are not implemented. These are exactly the areas where a thin wrapper stops adding value over using SkiaSharp directly — if you need them, use SkiaSharp (or SKCanvas/SKPaint) directly; AutoImage's AutoImageEditor does not hide access to anything, but also doesn't attempt to wrap every SkiaSharp API.

Install

dotnet add package Swevo.AutoImage

Linux/macOS: SkiaSharp's managed package alone only ships Windows native binaries. On Linux or macOS, also add the matching native asset package for your platform (e.g. dotnet add package SkiaSharp.NativeAssets.Linux, or SkiaSharp.NativeAssets.macOS), or use a base image that already provides libSkiaSharp.

Quick start

using AutoImage;

using var editor = AutoImageEditor.Load("input.jpg");

editor
    .Resize(800, 600, AutoImageResizeMode.Cover)
    .Brightness(0.1f)
    .Saturate(1.2f)
    .Watermark("© Swevo", AutoImageWatermarkPosition.BottomRight, opacity: 0.6f, fontSize: 28f)
    .Save("output.png", AutoImageFormat.Png);

Working in memory (e.g. inside an API endpoint):

using var editor = AutoImageEditor.Load(uploadedFileStream);
editor.Resize(320, 320, AutoImageResizeMode.Fit);

byte[] thumbnail = editor.ToBytes(AutoImageFormat.Webp, quality: 80);

Rotating and cropping:

using var editor = AutoImageEditor.Load("photo.jpg");

editor
    .Rotate90()                 // 90 degrees clockwise
    .Crop(x: 0, y: 0, width: 500, height: 500);

Applying filters:

using var editor = AutoImageEditor.Load("portrait.jpg");

editor
    .Blur(1.5f, 1.5f)
    .Sharpen()
    .Contrast(0.15f)
    .Save("portrait-enhanced.jpg", AutoImageFormat.Jpeg, quality: 90);

Adding watermarks:

using AutoImage;
using SkiaSharp;

using var editor = AutoImageEditor.Load("photo.jpg");
using var logo = SKBitmap.Decode("logo.png");

editor
    .Watermark("Draft", AutoImageWatermarkPosition.TopLeft, opacity: 0.35f, fontSize: 48f, color: SKColors.White)
    .Watermark(logo, AutoImageWatermarkPosition.BottomRight, opacity: 0.85f, scale: 0.5f)
    .Save("watermarked.png", AutoImageFormat.Png);

Or load the watermark image from a file path:

using var editor = AutoImageEditor.Load("photo.jpg");

editor
    .WatermarkImage("logo.png", AutoImageWatermarkPosition.BottomRight, opacity: 0.85f, scale: 0.5f)
    .Save("watermarked.png", AutoImageFormat.Png);

Resize modes

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License

MIT