Decode a Bitmap

using Imazen.WebP;

var decoder = new SimpleDecoder();
byte[] webpBytes = File.ReadAllBytes("image.webp");
using Bitmap bitmap = decoder.DecodeFromBytes(webpBytes, webpBytes.LongLength);

Decode to Raw Pixels (Cross-Platform)

using Imazen.WebP;

byte[] webpBytes = File.ReadAllBytes("image.webp");
byte[] pixels = WebPDecoder.Decode(webpBytes, out int width, out int height, WebPPixelFormat.Rgba);
// pixels is now width * height * 4 bytes of RGBA data

Encode from Raw Pixels (Cross-Platform)

using Imazen.WebP;

byte[] encoded = WebPEncoder.Encode(rgbaPixels, width, height, width * 4, WebPPixelFormat.Rgba, quality: 80);
File.WriteAllBytes("output.webp", encoded);

Advanced Encoding Config

using Imazen.WebP;

var config = new WebPEncoderConfig()
    .SetQuality(85)
    .SetMethod(6)           // Slowest, best compression
    .SetSharpYuv()          // Better color fidelity
    .SetSnsStrength(50)
    .SetFilterStrength(20);

var encoder = new SimpleEncoder();
using var bitmap = new Bitmap("input.png");
using var stream = File.Create("output.webp");
encoder.Encode(bitmap, stream, config);

Decode Animation

using Imazen.WebP;

byte[] animatedWebP = File.ReadAllBytes("animation.webp");
using var decoder = new AnimDecoder(animatedWebP);
Console.WriteLine($"{decoder.Info.FrameCount} frames, {decoder.Info.Width}x{decoder.Info.Height}");

foreach (var frame in decoder.DecodeAllFrames())
{
    // frame.Pixels = BGRA byte array for the full canvas
    // frame.TimestampMs, frame.DurationMs
}

Encode Animation

using Imazen.WebP;

using var encoder = new AnimEncoder(width, height, loopCount: 0);
encoder.AddFrame(frame1Bgra, timestampMs: 0, quality: 80);
encoder.AddFrame(frame2Bgra, timestampMs: 100, quality: 80);
encoder.AddFrame(frame3Bgra, timestampMs: 200, quality: 80);

byte[] animatedWebP = encoder.Assemble();
File.WriteAllBytes("animation.webp", animatedWebP);

Probe Image Info

using Imazen.WebP;

byte[] data = File.ReadAllBytes("image.webp");
var info = WebPInfo.GetImageInfo(data);
Console.WriteLine($"{info.Width}x{info.Height}, alpha={info.HasAlpha}, animated={info.HasAnimation}");

Packages

Platform Support

API Reference

Full API documentation is available at imazen.github.io/libwebp-net.

License

MIT — Copyright 2012–2026 Imazen LLC