exif-oxide

A high-performance Rust implementation of portions of ExifTool, providing fast metadata extraction from 26+ image and media file formats.

Goals

• Performance: 10-20x faster than Perl ExifTool for common operations
• Multi-Format: Support for JPEG, RAW (CR2, NEF, ARW, DNG), PNG, HEIF, WebP, MP4, and more
• Compatibility: Maintain ExifTool tag naming and structure (with Rust identifier constraints)
• Safety: Memory-safe handling of untrusted files
• Features: Embedded image extraction, XMP support

Why exif-oxide?

While ExifTool is the gold standard for metadata extraction, its Perl implementation can be slow for high-volume applications. exif-oxide aims to provide:

1. Sub-10ms metadata extraction for typical JPEG files
2. Native embedded preview/thumbnail extraction
3. ExifTool-compatible output for easy migration

Design

See DESIGN.md for architectural details and ALTERNATIVES.md for why we chose this approach.

Supported Formats

Image Formats: JPEG, TIFF, PNG, HEIF/HEIC, WebP
RAW Formats: CR2, NEF, ARW, DNG, PEF, ORF, RAF, RW2, SRW, 3FR, IIQ, MEF, MOS, MRW, CRW, SR2, NRW
Video Formats: MP4, M4V, MOV, 3GP, 3G2, AVI

Total: 26 formats with metadata extraction support

Quick Start

Library Usage

use exif_oxide::{read_basic_exif, extract_xmp_properties};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Extract basic EXIF metadata
    let exif = read_basic_exif("photo.jpg")?;
    
    println!("Camera: {} {}", 
        exif.make.as_deref().unwrap_or("Unknown"),
        exif.model.as_deref().unwrap_or("Unknown")
    );
    
    if let Some(orientation) = exif.orientation {
        println!("Orientation: {}", orientation);
    }
    
    // Read XMP metadata (hierarchical properties)
    let xmp_props = extract_xmp_properties("photo.jpg")?;
    for (key, value) in &xmp_props {
        println!("XMP {}: {}", key, value);
    }
    
    Ok(())
}

Command Line

# Build the project
cargo build --release

# Extract all EXIF data as JSON
cargo run --bin exif-oxide -- photo.jpg

# Extract specific tags
cargo run --bin exif-oxide -- -Make -Model photo.jpg

# Extract binary data (e.g., thumbnail)
cargo run --bin exif-oxide -- -b -ThumbnailImage photo.jpg > thumb.jpg

# Extract with group names
cargo run --bin exif-oxide -- -G photo.jpg

Testing

# Run all tests
cargo test

# Run specific feature tests
cargo test --test spike1   # Basic EXIF reading
cargo test --test spike2   # Canon maker notes  
cargo test --test spike3   # Thumbnail extraction
cargo test --test spike4_xmp  # XMP parsing

# Test with real images
cargo run --example debug_exif exiftool/t/images/Canon.jpg
cargo run --example debug_xmp_extraction test-images/canon/Canon_T3i.JPG

Development

Major Milestones Complete! ✅

Phase 0 - Synchronization Infrastructure: Complete

• Auto-generated maker note detection for all 10 manufacturers
• ProcessBinaryData table extraction with 530+ tags
• Table-driven PrintConv system achieving 96% code reduction
• Smooth regeneration system with zero manual maintenance

Phase 1 - Multi-Format Support: Complete

• 26 file formats supported (JPEG, RAW, PNG, HEIF, MP4, etc.)
• ExifTool-compatible metadata extraction
• Embedded binary extraction (thumbnails, previews)

EXIF Migration - Revolutionary Improvement: Complete ✅

• 28x improvement: 643 EXIF tags extracted vs previous ~23
• 87% coverage gap eliminated: Now extracting comprehensive EXIF data
• Table-driven architecture: Leveraging proven sync extractor pattern
• Zero regressions: All 123 tests passing with full backward compatibility

See:

• PHASE1-COMPLETE.md for Phase 1 summary
• EXIFTOOL-SYNC.md for synchronization infrastructure
• TODO-MIGRATE-EXIF-TO-SYNC.md for EXIF migration details

Next Steps (Phase 2-4):

• Additional manufacturer maker notes (Ricoh, PhaseOne, Qualcomm, Red expansion)
• Metadata writing capabilities with safety guarantees
• Performance optimizations (SIMD, parallel processing)
• Async API and plugin system

License

This project is licensed under the same terms as ExifTool: GNU General Public License v3 (GPL-3.0)

ExifTool is free and open-source software that allows personal, commercial, and any other use without separate licensing fees.

Tag Naming Compatibility

ExifTool tag names are preserved when possible, but tags with invalid Rust identifier characters are modified:

• ExifTool: "NikonActiveD-Lighting"
• exif-oxide: "NikonActiveD_Lighting"

Hyphens are converted to underscores to maintain valid Rust identifiers while preserving semantic meaning.

Acknowledgments

• Phil Harvey for creating and maintaining ExifTool for 25 years
• The Rust community for excellent binary parsing libraries