LegioSoft.Imaging.WebP 1.0.0-beta3

LegioSoft.Imaging.WebP

WebP codec wrapper using native libwebp v1.6.0. High-performance WebP encoding and decoding with support for multiple color formats.

Installation

dotnet add package LegioSoft.Imaging.WebP

Features

• Encoding - RGBA, RGB, BGRA, BGR formats with lossless/lossy compression
• Decoding - Multiple colorspaces (RGBA, RGB, BGRA, BGR, ARGB)
• Transformation - Scale, crop, and flip images during encoding/decoding
• Advanced Options - Fine-tune compression quality, method, filters, and alpha settings
• Metadata - Extract image dimensions, alpha channel, animation, and format type
• Cross-Platform - Windows, Linux, macOS native library support

Core Classes

• WebPImage - High-level static API for encoding, decoding, and transformations
• WebPEncoder - Low-level encoder with advanced options
• WebPDecoder - Low-level decoder with scaling, cropping, and flip support
• WebPEncodeOptions - Advanced encoding configuration (quality, method, filters, alpha)
• WebPInfo - WebP image metadata (width, height, format, alpha, animation)
• WebPValidationHelper - WebP format validation

Usage

Basic Encoding

using LegioSoft.Imaging.WebP;

// Encode RGBA data to WebP
byte[] rgbaData = File.ReadAllBytes("image.rgba");
byte[] webpData = WebPImage.Encode(rgbaData, width, height, quality: 75);

// Encode with lossless compression
byte[] lossless = WebPImage.EncodeLossless(rgbaData, width, height);

// Encode RGB data
byte[] rgbData = File.ReadAllBytes("image.rgb");
byte[] webpData = WebPImage.EncodeRGB(rgbData, width, height, quality: 80);

Advanced Encoding

var options = new WebPEncodeOptions
{
    Quality = 80.0f,
    Lossless = false,
    Method = 6,
    FilterStrength = 60,
    Autofilter = true,
    AlphaQuality = 90
};

byte[] webpData = WebPImage.EncodeAdvanced(rgbaData, width, height, options);

Basic Decoding

// Decode WebP to RGBA
byte[] webpData = File.ReadAllBytes("image.webp");
byte[] rgbaData = WebPImage.Decode(webpData);

// Decode with specific colorspace
byte[] bgrData = WebPImage.Decode(webpData, WEBP_CSP_MODE.MODE_BGR);

// Decode from file or stream
byte[] data = WebPImage.Decode("image.webp");
using var stream = File.OpenRead("image.webp");
byte[] data = WebPImage.Decode(stream);

Decoding with Transformations

// Scale during decode
byte[] scaled = WebPImage.Scale(webpData, 640, 480);

// Crop during decode
byte[] cropped = WebPImage.Crop(webpData, cropX: 10, cropY: 10, cropWidth: 200, cropHeight: 200);

// Flip vertically during decode
byte[] flipped = WebPImage.Flip(webpData);

Image Info

WebPInfo info = WebPImage.GetInfo(webpData);
Console.WriteLine($"Dimensions: {info.Width}x{info.Height}");
Console.WriteLine($"Has Alpha: {info.HasAlpha}");
Console.WriteLine($"Animated: {info.HasAnimation}");
Console.WriteLine($"Format: {info.Format}");

Encoding with Transformations

// Encode with scaling
byte[] scaled = WebPImage.EncodeWithScaling(rgbaData, width, height, targetWidth: 640, targetHeight: 480);

// Encode with cropping
byte[] cropped = WebPImage.EncodeWithCropping(rgbaData, width, height, cropX: 10, cropY: 10, cropWidth: 200, cropHeight: 200);

Validation

byte[] imageData = File.ReadAllBytes("file.webp");
bool isValidWebP = WebPImage.IsValidWebP(imageData);

Version Info

string version = WebPImage.GetVersion();
Console.WriteLine($"libwebp version: {version}");

Encoding Options

WebPEncodeOptions provides advanced control:

• Preset - DEFAULT, PICTURE, PHOTO, DRAWING, ICON, TEXT
• Quality - 0-100 quality level
• Lossless - Enable lossless compression
• Method - 0-6 (faster to better compression)
• ImageHint - DEFAULT, PICTURE, PHOTO, GRAPH
• FilterStrength - 0-100 filter strength
• FilterSharpness - 0-7 filter sharpness
• Autofilter - Enable automatic filter adjustment
• AlphaCompression - 0-1 alpha compression mode
• AlphaFiltering - 0-2 alpha filtering
• AlphaQuality - 0-100 alpha channel quality

Platform Support

• .NET 6.0, 7.0, 8.0, 9.0, 10.0
• Windows (x64)
• Linux (x64, ARM64)
• macOS (supported via native library)

Dependencies

• LegioSoft.Imaging.Core - Core interfaces and types
• libwebp v1.6.0 native library (included)

License

Apache License 2.0