Crate xmpkit 

XMPKit - Pure Rust implementation of Adobe XMP Toolkit

XMPKit is a pure Rust implementation of Adobe’s XMP (Extensible Metadata Platform) Toolkit. It provides APIs for reading, writing, and manipulating XMP metadata in various file formats without c++ SDK bridge.

Features

• Pure Rust implementation
• Compatible with Adobe XMP standard
• Support for common file formats (e.g., JPEG, PNG, TIFF, MP3, GIF, MP4)
• Memory safe and high performance
• Cross-platform support (iOS, Android, HarmonyOS, macOS, Windows, Linux, Wasm)

Quick Start

Working with Files (Native Platforms)

use xmpkit::{XmpFile, XmpMeta, XmpValue};
use xmpkit::core::namespace::ns;

// Open a file
let mut file = XmpFile::new();
file.open("image.jpg")?;

// Read XMP metadata
if let Some(meta) = file.get_xmp() {
    if let Some(creator) = meta.get_property(ns::XMP, "CreatorTool") {
        println!("Creator: {:?}", creator);
    }
}

// Modify metadata
if let Some(mut meta) = file.get_xmp().cloned() {
    meta.set_property(
        ns::XMP,
        "CreatorTool",
        XmpValue::String("MyApp".to_string()),
    )?;
    file.put_xmp(meta);
}

// Save changes
file.save("output.jpg")?;

Working with Bytes (Wasm and Memory-based Operations)

use xmpkit::{XmpFile, XmpMeta, XmpValue};
use xmpkit::core::namespace::ns;

let jpeg_data: &[u8] = &[]; // your JPEG file data

// Load from bytes
let mut file = XmpFile::new();
file.from_bytes(jpeg_data)?;

// Read and modify metadata
if let Some(mut meta) = file.get_xmp().cloned() {
    meta.set_property(
        ns::XMP,
        "CreatorTool",
        XmpValue::String("MyApp".to_string()),
    )?;
    file.put_xmp(meta);
}

// Write back to bytes
let output_data = file.write_to_bytes()?;

Parsing XMP from String

use xmpkit::{XmpMeta, XmpValue};
use xmpkit::core::namespace::ns;

let xmp_packet = r#"<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/">
  <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
    <rdf:Description rdf:about="" xmlns:xmp="http://ns.adobe.com/xap/1.0/">
      <xmp:CreatorTool>MyApp</xmp:CreatorTool>
    </rdf:Description>
  </rdf:RDF>
</x:xmpmeta><?xpacket end="w"?>"#;

let meta = XmpMeta::parse(xmp_packet)?;

if let Some(creator) = meta.get_property(ns::XMP, "CreatorTool") {
    println!("Creator: {:?}", creator);
}

// Modify and serialize
let mut meta = meta;
meta.set_property(
    ns::XMP,
    "ModifyDate",
    XmpValue::DateTime("2024-01-01T00:00:00Z".to_string()),
)?;

let serialized = meta.serialize_packet()?;

Modules

• core - Core XMP functionality (parsing, serialization, metadata API)
• files - File format handlers for reading/writing XMP from files
• types - Common types and data structures (XmpValue, Qualifier)
• utils - Utility functions (date/time handling)

Platform Support

Native Platforms (iOS, Android, HarmonyOS, macOS, Windows, Linux)

Native platforms support both file I/O and memory-based operations:

• XmpFile::open() - Open files from file system
• XmpFile::save() - Save files to file system
• XmpFile::from_bytes() - Load from memory (also available)
• XmpFile::write_to_bytes() - Write to memory (also available)

WebAssembly (Wasm)

Wasm platforms support memory-based operations only:

• XmpFile::from_bytes() - Load from memory
• XmpFile::from_reader() - Load from reader
• XmpFile::write_to_bytes() - Write to memory
• XmpFile::write_to_writer() - Write to writer

To use xmpkit in JavaScript, enable the wasm feature:

Simple way (recommended):

1. Create a new crate: cargo new --lib my-wasm-app
2. Add to Cargo.toml:

   [lib]
   crate-type = ["cdylib"]
   [dependencies]
   xmpkit = { version = "0.1.0", features = ["wasm"] }

3. Re-export bindings in src/lib.rs:

   pub use xmpkit::wasm::*;

4. Build: wasm-pack build --target web

Then use in JavaScript:

import init, { read_xmp, write_xmp } from './pkg/my_wasm_app.js';
await init();
const result = read_xmp(new Uint8Array(/* file bytes */));

Alternative: Create a custom binding crate (see docs/WEBASSEMBLY.md for details)

OpenHarmony/HarmonyOS (ArkTS)

To use xmpkit in OpenHarmony/HarmonyOS applications, enable the ohos feature:

1. Add to Cargo.toml:

   [lib]
   crate-type = ["cdylib"]
   [dependencies]
   xmpkit = { version = "0.1.0", features = ["ohos"] }

2. Re-export bindings in src/lib.rs:

   pub use xmpkit::ohos::*;

3. Build: ohrs build

Then use in ArkTS:

import { XmpFile, XmpMeta } from 'libxmpkit.so';
const file = new XmpFile();
file.fromBytes(fileBytes);
const meta = file.getXmp();

Feature Flags

• core - Core XMP functionality (enabled by default)
• files - File format support infrastructure (enabled by default)
• jpeg, png, tiff, mp3, gif, mpeg4 - Individual file format handlers
• full-formats - Enable all file format handlers (enabled by default)
• mutli-thread - Multi-threaded runtime support (enabled by default)
• wasm - WebAssembly JavaScript bindings (optional, enables wasm-bindgen integration)
• ohos - OpenHarmony/HarmonyOS Node-API bindings (optional, enables napi-ohos integration)

Supported File Formats

Format	Extensions	Read	Write
JPEG	.jpg, .jpeg	Yes	Yes
PNG	.png	Yes	Yes
TIFF	.tif, .tiff	Yes	Yes
MP3	.mp3	Yes	Yes
GIF	.gif	Yes	Yes
MPEG4	.mp4, .m4a, .m4v, .mov	Yes	Yes

Re-exports

pub use core::error::XmpError;

pub use core::error::XmpResult;

pub use core::metadata::XmpMeta;

pub use core::namespace::get_all_registered_namespaces;

pub use core::namespace::get_builtin_namespace_uris;

pub use core::namespace::get_global_namespace_prefix;

pub use core::namespace::get_global_namespace_uri;

pub use core::namespace::is_namespace_registered;

pub use core::namespace::ns;

pub use core::namespace::register_namespace;

pub use files::XmpFile;

pub use files::XmpOptions;

pub use types::qualifier::Qualifier;

pub use types::value::XmpValue;

pub use utils::datetime::XmpDateTime;

Modules

core

XMP Core module

files

File format support for XMP

types

XMP value types

utils

Utility functions