XMP Toolkit SDK

The XMP Toolkit SDK is composed of two primary C++ libraries that work together to manage metadata:

1. XMPCore: Provides the API for parsing, manipulating, and serializing metadata according to the XMP data model. It is format-agnostic, meaning it handles the metadata logic regardless of the file format being described.
2. XMPFiles: Provides the API for locating, adding, or updating XMP metadata within specific files. It allows you to retrieve an entire XMP Packet, which can then be passed to XMPCore for property-level manipulation.

XMPFiles Plug-in SDK: Included within the XMPFiles component, this allows you to create plug-ins to handle metadata for additional file formats or to replace built-in format handlers with custom ones.

Before using the SDK, you should be familiar with the XMP Data Model. The XMP Specification is divided into three parts:

• Part 1: Data Model, Serialization, and Core Properties: Covers the basic metadata representation model, how metadata is organized (Data Model), and how it is represented in XML/RDF (Serialization Model).
• Part 2: Additional Properties: Provides property lists and descriptions for standard schemas (e.g., Dublin Core) and Adobe-specific schemas (e.g., Photoshop), as well as instructions for creating new schemas.
• Part 3: Storage in Files: Explains how serialized XMP metadata is packaged into XMP Packets and embedded into various file formats, including how to reconcile multiple metadata formats.

The SDK provides build scripts to facilitate the creation of project files across multiple platforms, including Mac OS®, Windows®, UNIX®/Linux®, iOS, and Android.

To build the SDK:

1. Navigate to the build/ directory.
2. Use the provided Batch files, shell scripts, Makefiles, or CMake scripts to generate the appropriate project files for your platform.
3. Follow the specific instructions located in build/README.txt to complete the project creation process.

For a detailed, step-by-step walkthrough of the build process, refer to the Programmer's Guide.

The XMP Toolkit requires an external XML parser to function. While the Adobe source is written specifically for Expat, the architecture allows for adapters to be written for other parsers. To use Expat, you must provide the Expat distribution files in a specific directory structure within the SDK.

Requirements:

• An Expat distribution (version 2.5.0 is the most recent version used with XMP).
• The Expat lib directory must be placed within the third-party/expat directory of the XMP Toolkit SDK (as a sibling to this README file).

The XMP Toolkit SDK requires zlib (specifically version 1.2.13 is used in this release) to function. To set up the dependency:

1. Download the zlib source code (not a compiled .dll) from http://www.zlib.net/.
2. Extract the downloaded archive.
3. Copy all top-level .c and .h files from the zlib source directly into the .../third-party/zlib directory within the XMP Toolkit SDK project structure.

The dumpfile utility is a developer tool used to view and validate file structures, specifically focusing on metadata. It acts similarly to a hex editor but is more readable.

Note: dumpfile is NOT a production tool. It does not perform XMP logic reconciliation, handle encoding matters, or extract valid metadata for use in applications. It is intended for structural inspection only.

# Show key-value nodes as an alphabetical list
dumpfile -keys Sample.jpg

# Show the hierarchical tree structure (default)
dumpfile Sample.jpg

# Show key-value nodes in the order they were parsed
dumpfile -list Sample.jpg

# Suppress comments in the output
dumpfile -nocomments Sample.jpg

Before using any SXMPMeta functionality, you must initialize the XMPCore library. Once your operations are complete, you must call terminate to clean up resources. Failure to initialize will result in errors when calling other SDK methods.

// Initialize the SDK
if (!SXMPMeta::Initialize()) {
    // Handle initialization failure
}

// ... perform XMP operations ...

// Clean up the SDK
SXMPMeta::Terminate();

You can retrieve the version information of the statically linked XMPCore library using SXMPMeta::GetVersionInfo. This is useful for verifying compatibility and debugging.

XMP_VersionInfo coreVersion;
SXMPMeta::GetVersionInfo(&coreVersion);
// coreVersion.message contains the version string