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# About Gateway Clip Files

First, some disambiguation as there are two types of clips using the Gateway denomination:

- Gateway library clips: Clips that are imported through a Gateway library or a Gateway Import node. In this context, it relates to the method of importing media (through a Gateway), not the type of clip (which can be a RED, a multi-layer OpenEXR, a DPX sequence...).
- Gateway .clip files: Files that are created using the Export node in Batch or by a third party application. It is this format that we discuss here.

How to Create a Gateway Clip?

Three ways to create a Gateway clip:

- Using the Batch Export node with Create Clip Data is enabled.
- Using a third party application or utility.
- Creating one by hand

What Is a Gateway .Clip File?

In its simplest form, a Gateway .clip file consists of two parts:

- A .clip file
- Media files

The media is any supported media files, from DPX sequences to RED clips, including multi-channel OpenEXR renders. The other component, the .clip file, is written in a human-readable format, the XML format; you can open a .clip in any word processor (kedit, notepad, TextEdit) and decipher its content. Here is a simplified example.

In essence, the .clip files contains all the metadata and references to media that are required to define a source and its versions. The .clip file does nothing by itself, but is essential to recreate the sources.

One of the strenght of the Gateway .clip is that anyone can create .clip files. With one you can organize media outside of your applications for later use in Flame 2012, Smoke 2012, and Lustre 2012.

Using a Gateway .clip file, you can define many aspects of a Gateway Clip, including:

- Source Information
- Versioning
- Multiple channels of media
- Paths to media

Because the Gateway Clip XML is supported by the Wiretap Gateway, reading of these files is supported by any Wiretap Gateway client application.

Why Use a Gateway Clip?

For open clip history and data exchange.

Open clip history
  Open clip history provides you with the ability to save with a processed clip the Batch setup used to create that clip. Later on, to open that clip in Batch and edit previous nodes and their settings.
Data exchange
  Data exchange requirements with a facility's shot management system. In such a case, the .clip is a file created by a third party system, allowing something else to define a source using instructions contained within the file. In this case, the clip can contain a list of render passes for you to composite in Flame. Using of the Gateway Import node, you can easily navigate a source's versions.

#### Topics in this section

- Gateway Clip Example