About XMP metadata

Metadata is—in the simplest sense—data about data. In practical terms, metadata is a set of standardized information about a file, such as author name, resolution, color space, copyright, and keywords applied to the file. For example, most cameras attach some basic information to video files, such as date, duration, and file type. Other metadata can be entered as shot-list information in OnLocation or at the capture stage in Adobe Premiere Pro. You can add additional metadata with properties such as location, author name, and copyright. Because you can share, view, and use this metadata across Adobe Creative Suite applications, you can use this information to streamline your workflow and organize your files.

The Extensible Metadata Platform (XMP) is the metadata standard used by Adobe applications. Metadata that is stored in other formats—such as Exif, IPTC (IIM), GPS, and TIFF—is synchronized and described with XMP so that it can be more easily viewed and managed. For example, adjustments made to images with Adobe Camera Raw are stored as XMP metadata. The XMP standard is based on XML.

In most cases, XMP metadata for a file is stored in the file itself. If it isn’t possible to write the information directly into the file, XMP metadata is stored in a separate file called a sidecar file, with the filename extension .xmp. For information on which file formats After Effects can write XMP metadata directly into, see Importing files with XMP metadata into After Effects.

In most cases, XMP metadata remains with the file even when the file is converted to a different format—for example, from PSD to JPG. XMP metadata is also retained when files are placed in a document or project in an Adobe Creative Suite application.

A metadata schema is a collection of properties specific to a given workflow. The Dynamic Media schema, for example, includes properties such as Scene and Shot Location that are tailored for digital video projects. Exif schemas, by contrast, include properties tailored to digital photography, such as Exposure Time and Aperture Value. More general properties, such as Date and Title, appear in the Dublin Core schema. To see a tool tip with information about a specific schema or property, place the pointer over it in the Metadata panel. You can create your own schemas using commands in the Metadata panel, and you can import schemas and share them with others as XML files.

Metadata is divided into two general categories: static metadata and temporal metadata. Static metadata is metadata that applies to an entire asset. For example, the copyright and author information for a video clip apply to the entire clip. Temporal metadata is metadata that is associated with a specific time within a dynamic media asset. Beat markers from Soundbooth and the metadata generated by the Speech Search feature in Soundbooth and Premiere Pro are examples of temporal metadata.

The Speech Search feature in Adobe Premiere Pro and Adobe Soundbooth provides the ability to convert speech in a video or audio asset to text metadata. Each word is stored as a metadata element at the corresponding time in the timeline. When a file with Speech Search metadata is imported into After Effects and used as the source for a layer, each word appears in a layer marker at the corresponding time. (This assumes that the Create Layer Markers From Footage XMP Metadata is selected. See Working with XMP metadata in After Effects.)

You can view static XMP metadata for a file in Adobe Bridge.

After Effects scripts and expressions can read and use data stored in markers. Because XMP metadata for source footage items can be converted to layer markers, expressions and scripts can work with XMP metadata. Scripts can also operate on the XMP metadata for a file outside of the After Effects context, both for the automation of common tasks and for creative uses.

XMP metadata included in an F4V or FLV file can be read and used by ActionScript, so you can use XMP metadata to add interactivity to a video playing in Flash Player. One application of this feature is searching within an FLV file for temporal metadata, which can allow the user to begin playback at a specific word of dialog or at some other time associated with a specific temporal metadata element.

Dan Ebberts provides a tutorial about XMP metadata on the After Effects Developer Center. The tutorial provides step-by-step instructions for using the XMP metadata features in Adobe Creative Suite CS4 Production Premium Edition. The motivating example in the tutorial is the transcription of speech to text and the creation of a simple video player with which you can navigate to the places where those words are spoken. Along the way, the XMP metadata is used to speed up editing, to check for copyright information, and to create simple subtitles (captions).

Go to the XMP Developer Center section of the Adobe website for the XMP specification, information on integrating XMP metadata with your software and workflow, the XMP SDK (software development kit), and forums about XMP metadata.

To view video tutorials on working with markers and XMP metadata go to the Adobe website: