Metadata Utility Library Overview

This document provides an overview of the Metadata Utility Library.

Purpose

The Metadata Utility Library provides fast metadata access to audio, video and image media files. It provides a consistent interface, independent of the underlying parser implementations.

Metadata Utility Library Details

The DLL that provides the functionality and the library to which your code must link is identified below.

DLL	LIB	Short Description
metadatautility.dll	metadatautility.lib	These files are used to implement the Metadata Utility Library.

Architectural Relationship

Metadata Utility Library consists of a client utility, a framework implementation and a parser plug-in interface. These components interact with metadata clients and parser plug-ins. The following figure shows the architectural relationship of the Metadata Utility Library:

Figure 1. Metadata Utility Library Architecture

Description

The Metadata Utility Library consists of three main elements, these are:

Metadata Client Utility

The client utility allows clients to access various parser-specific functionality.
Metadata Utility Framework

The framework handles client requests for metadata, loads parsers, and delegates requests to a parser plug-in.
Parser Plug-in Interface

The Metadata Utility Library uses parser plug-ins to parse media files and extract their metadata either synchronously or asynchronously. The parser plug-in interface defines an abstract class for parser plug-in implementations.

The Metadata Utility Library also provides the following utility items:

A generic enum structure for metadata fields.
A metadata buffer structure.

Key Metadata Utility Library Classes

The functionality provided by the Metadata Utility Library is contained within the following classes:

CMetaDataClientUtility - implements the client utility.
CMetaDataUtilityBody - implements the metadata framework.
MMUFObserver - provides a callback interface between the framework and the client.
CMetaDataParser - base class for parser plug-ins.
MMUFParserObserver - provides a callback interface between the framework and the parser plug-in.

Using Metadata Utility Library

You can use the Metadata Utility Library to:

Create a new metadata utility object.
Configure parser loading options.
Check whether a media format is supported.
Extract metadata field items from a media file.