ImageSharp
A modern, cross-platform, 2D Graphics library for .NET
...Complete support for jpeg, bmp, gif, pbm, png, tga, tiff, and webp with more formats on the way. Supports over 25 different pixel formats. Metadata editing support (IPTC EXIF). Colorspace transforms (RGB/CMYK/Grayscale/CIELab and many more). Over 40 common processing operations. Great performance and memory friendly; work with any dimensions (even hundreds of megapixels). ImageSharp is brimming with features. Common operations are only a few keystrokes away.