Quantumm.Image

Quantumm.Image is an asynchronous, thread-safe, LRU-aware image caching and downloading library designed for Avalonia applications. It provides fast and memory-efficient image loading and downloading with support for dependency injection and duplicate download prevention.

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Features

• Asynchronous image loading from disk
• Asynchronous image downloading from a URL to a user-specified folder
• Memory-limited LRU (Least Recently Used) caching
• Thread-safe access to cached images
• Automatic eviction of least recently used images
• Prevents multiple concurrent loads of the same image
• Easy dependency injection integration with Microsoft.Extensions.DependencyInjection
• Optional logging via Microsoft.Extensions.Logging
• Detailed XML documentation for all public interfaces
• Supports Avalonia 11 and .NET 9

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Installation

Install via NuGet:

dotnet add package Quantumm.Image --version 1.1.6

Usage

1. Register the service in your DI container

   using Microsoft.Extensions.DependencyInjection;
   using Quantumm.Image.Services.DependencyInjection;
   
   var services = new ServiceCollection();
   
   // Register ImageCacheService with optional capacity (default 100)
   services.AddImageCache(capacity: 200);
   
   // Register ImageDownloadService
   services.AddHttpClient<IImageDownloadService, ImageDownloadService>();
   
   var serviceProvider = services.BuildServiceProvider();

2. Resolve and use IImageCacheService

    using Quantumm.Image.Services.Cache;
    using Avalonia.Media.Imaging;
    
    var imageCache = serviceProvider.GetRequiredService<IImageCacheService>();
    
    // Load an image asynchronously
    Bitmap image = await imageCache.LoadImage("path/to/image.png");
    
    // Update an image in cache if the file has changed
    Bitmap updatedImage = await imageCache.UpdateImage("path/to/image.png");

3. Resolve and use IImageDownloadService via DI

    using Quantumm.Image.Services.Downloader;
   
    var imageDownloader = serviceProvider.GetRequiredService<IImageDownloadService>();
   
    // Download an image to a folder
    string savedPath = await imageDownloader.DownloadImageAsync("https://example.com/image.png", "image.png", "C:\\Images");
   
    Console.WriteLine($"Image saved to: {savedPath}");

API

IImageCacheService

• Task<Bitmap> LoadImage(string filePath) Loads an image from cache or disk asynchronously. Adds it to the cache if it wasn't already present.

• Task<Bitmap> UpdateImage(string path) Updates an existing image in the cache by loading a new version from disk. Adds it if it does not exist.

IImageDownloadService

• Task<string> DownloadImageAsync(string? url, string fileName, string folderPath, CancellationToken cancellationToken = default) Downloads an image from a given URL and saves it to the specified folder. Throws exceptions on failure. Logs if a logger is provided.

Logging

Both ImageCacheService and ImageDownloadService support optional logging via Microsoft.Extensions.Logging. If a logger is provided, the following events are logged:

• Image loading and updating
• Cache eviction
• Download start, completion, and errors
• Errors during file system operations

Example:

services.AddLogging(builder => builder.AddConsole());

Supported Platforms

• Avalonia 11
• .NET 9.0

License

MIT License. See LICENSE for details.

Contributors

See all contributors