qoi-unity

Unity plugin for encoding & decoding QOI format images (https://qoiformat.org/qoi-specification.pdf).

Implementation is split into:

• a zero allocation pure C# (QOI) ReadOnlySpan/Span based "namespace" static class; very much based on the reference C implementation (https://github.com/phoboslab/qoi) with two minor changes:
  1. decoding has been separated into DecodeHeader and Decode (so that we get a chance to create an appropriately sized Span to decode into)
  2. flipVertically has been added to both encoding & decoding since gfx texture resources are typically flipped vertically compared to raster image data
• a Unity layer QOIUnity that can decode into or encode from a Unity Texture2D
  • uses NativeArrayUnsafeUtility to work directly with the native pixel data (at the appropriate mip-level if required)
  • only RGBA32 and RGB24 texture formats are supported
  • encoding does require the source Texture2D to be readable

The sample Unity project includes a test UGUI scene that loads, displays & saves the test images referenced in https://qoiformat.org/

Prerquisites:

• Tested with Unity 2021.3.16f1