Skip to content

C# .NET Standard PNG decoder and PNG library

License

Notifications You must be signed in to change notification settings

ThomasHoevel/BigGustave

 
 

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

51 Commits
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

Big Gustave

NuGet

Open, read and create PNG images in fully managed C#.

Usage

To open a PNG image from file and get some pixel values:

using (var stream = File.OpenRead(@"C:\my\file\path\file.png"))
{
    Png image = Png.Open(stream);

    Pixel pixel = image.GetPixel(image.Width - 1, image.Height - 1);

    int pixelRedAverage = 0;

    pixelRedAverage += pixel.R;

    pixel = image.GetPixel(0, 0);

    pixelRedAverage += pixel.R;

    Console.WriteLine(pixelRedAverage / 2.0);

}

The PNG object has methods to inspect the header and get the pixel values. The header has properties for:

png.Header.Width
png.Header.Height
png.Header.BitDepth
png.Header.ColorType
png.Header.CompressionMethod
png.Header.FilterMethod
png.Header.InterlaceMethod

The PNG also has width and height as convenience properties from the header information:

png.Width == png.Header.Width
png.Height == png.Header.Height

And a property that indicates if the image uses transparency:

png.HasAlphaChannel

To get a pixel use:

Pixel pixel = png.GetPixel(0, 7);

Where the first argument is x (column) and the second is y (row). The Pixel is used for all image types, e.g. Grayscale, Colour, with/without transparency.

Creation

To create a PNG use:

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

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

builder.SetPixel(red, 0, 0);
builder.SetPixel(255, 120, 16, 1, 1);

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

    return memory.ToArray();
}

You can also load a PNG into a builder which will copy all the pixel values into the builder for easy editing:

var png = Png.Open(@"C:\files\my.png");
var builder = PngBuilder.FromPng(png);

About

C# .NET Standard PNG decoder and PNG library

Resources

License

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published

Languages

  • C# 100.0%