Aseprite.CSharp

Aseprite.CSharp is a lightweight C# library for reading .ase and .aseprite files — the native formats of Aseprite — and extracting their animation, layer, cel, palette, and metadata information. It supports asynchronous reading and optional cel decompression.

📄 ASE File Format Specification

Features

• Asynchronously load .aseprite files.
• Read all core metadata: frames, layers, cels, palette, slices, tags, user data, and more.
• Optionally decompress cel image data during loading, or handle it manually.

Usage

using var stream = File.OpenRead("sprite.aseprite");
var aseFile = await AsepriteFile.ReadAsync(stream, decompressCels: true);

Decompression

If decompressCels is set to false, compressed cel image data will remain in its original form. You can manually decompress it later using the provided methods:

var decompressed = AsepriteFile.Decompress(compressedMemory);
// or
int bytesWritten = AsepriteFile.DecompressInto(compressedMemory, buffer, offset, length);

API

public sealed record AsepriteFile(
	AsepriteHeader Header,
	ReadOnlyMemory<AsepriteFrame> Frames,
	ReadOnlyMemory<AsepriteLayer> Layers,
	ReadOnlyMemory<ReadOnlyMemory<AsepriteCel?>> Cels,
	AsepriteColorProfile? ColorProfile,
	AsepriteExternalFiles? ExternalFiles,
	ReadOnlyMemory<AsepriteTag> Tags,
	ReadOnlyMemory<PaletteEntry> Palette,
	Dictionary<AsepriteObject, AsepriteUserData> UserDatas,
	ReadOnlyMemory<AsepriteSlice> Slices)
{
	public static Task<AsepriteFile> ReadAsync(Stream stream, bool decompressCels, CancellationToken cancellationToken = default);

	public static ReadOnlyMemory<byte> Decompress(ReadOnlyMemory<byte> memory);

	public static int DecompressInto(ReadOnlyMemory<byte> input, byte[] output, int offset, int length);
}

License

Apache 2.0