Crate mediagit_compression 

Intelligent compression for MediaGit

This crate provides compression abstractions and implementations:

• Smart compression: Automatic per-object-type strategy selection
• Zstd compression: Fast, good compression ratios (default)
• Brotli compression: Higher compression, slower (for archival)
• Auto-detection: Transparently handle compressed vs uncompressed data
• Compression levels: Configurable speed vs compression trade-offs

Quick Start

Basic Compression

use mediagit_compression::{Compressor, CompressionLevel, ZstdCompressor};

fn main() -> anyhow::Result<()> {
    let compressor = ZstdCompressor::new(CompressionLevel::Default);

    let original = b"Hello, World!";
    let compressed = compressor.compress(original)?;
    let decompressed = compressor.decompress(&compressed)?;

    assert_eq!(original, &decompressed[..]);
    println!("Original: {} bytes, Compressed: {} bytes",
        original.len(), compressed.len());

    Ok(())
}

Smart Type-Aware Compression

use mediagit_compression::{SmartCompressor, TypeAwareCompressor, ObjectType};

fn main() -> anyhow::Result<()> {
    let compressor = SmartCompressor::new();

    // Automatically selects best strategy based on file type
    let text_data = b"Some text content...";
    let compressed = compressor.compress_typed(text_data, ObjectType::Text)?;

    // Already compressed formats stored without recompression (with Store prefix)
    let jpeg_data = vec![0xFF, 0xD8, 0xFF, 0xE0];
    let stored = compressor.compress_typed(&jpeg_data, ObjectType::Jpeg)?;
    assert_eq!(stored[0], 0x00); // Store mode magic byte
    assert_eq!(&stored[1..], &jpeg_data[..]); // No recompression overhead

    Ok(())
}

Compression Algorithms

Zstd (Default)

• Fast compression and decompression
• Good compression ratios (typical 2-4x for text/structured data)
• Low memory usage
• Ideal for frequently accessed data

Brotli

• Higher compression ratios (typical 3-8x for text/structured data)
• Slower compression but faster decompression than gzip
• Good for archival and infrequently accessed data
• Higher memory usage during compression

Per-Object Type Strategies

SmartCompressor automatically selects optimal compression:

• Already compressed (JPEG, PNG, MP4, ZIP): Store without recompression
• Uncompressed images (TIFF, BMP, PSD, RAW): Zstd Best compression
• Text/Code (TXT, JSON, XML, YAML): Brotli Best for maximum text compression
• Documents (PDF, SVG): Zstd Default for balanced performance
• Unknown/Binary: Zstd Default as safe fallback

Re-exports

pub use adaptive::calculate_entropy;

pub use adaptive::AdaptiveCompressor;

pub use adaptive::CompressionStrategy as AdaptiveStrategy;

pub use adaptive::EntropyClass;

pub use adaptive::FileProfile;

pub use adaptive::PatternClass;

pub use adaptive::PerformanceStats;

pub use adaptive::SizeClass;

pub use brotli_compressor::BrotliCompressor;

pub use error::CompressionError;

pub use error::CompressionResult;

pub use metrics::AggregatedStats;

pub use metrics::CompressionMetrics;

pub use metrics::MetricsAggregator;

pub use per_type_compressor::CompressionProfile;

pub use per_type_compressor::PerObjectTypeCompressor;

pub use per_type_compressor::PerTypeStats;

pub use smart_compressor::CompressionStrategy;

pub use smart_compressor::ObjectCategory;

pub use smart_compressor::ObjectType;

pub use smart_compressor::SmartCompressor;

pub use smart_compressor::TypeAwareCompressor;

pub use zlib_compressor::ZlibCompressor;

pub use zstd_compressor::ZstdCompressor;

Modules

adaptive

Adaptive compression based on file characteristics

brotli_compressor

Brotli compression implementation

delta

Delta encoding implementation using bsdiff

error

Compression error types

metrics

Compression metrics and statistics

per_type_compressor

Per-object-type compression with configurable profiles

smart_compressor

Smart compression with per-object-type strategy selection

zlib_compressor

Zlib compression implementation for Git compatibility

zstd_compressor

Zstd compression implementation

Enums

CompressionAlgorithm

Compression algorithm identifier

CompressionLevel

Compression level configuration

Traits

Compressor

Compressor trait for pluggable compression implementations