I wanted a platform independent way to open and create PNG images in C#. BigGustave is a new library which provides a .NET Standard 2.0 compatible way of opening and creating PNG images.

To open a png image you can pass either the bytes or the stream of the image to Png.Open and then retrieve the values for pixels at any location in the image:

Png png = Png.Open(File.ReadAllBytes(@"C:\pictures\example.png"));
Pixel first = png.GetPixel(0, 0);
Console.WriteLine($"R: {first.R}, G: {first.G}, B: {first.B}");

To create a .png image in C# use the PngBuilder to define pixel values before saving to an output stream:

var builder = PngBuilder.Create(2, 2, false);

var red = new Pixel(255, 0, 0);

builder.SetPixel(red, 0, 0);
builder.SetPixel(red, 1, 1);

using (var memory = new MemoryStream())
{
    builder.Save(memory);

    return memory.ToArray();
}

BigGustave is completely open source and is available on NuGet now so if you need very basic PNG manipulation tools for platform independent .NET code why not check it out?