Rendering and exporting overview



Rendering is the creation of the frames of a movie from a composition. The rendering of a frame is the creation of a composited two-dimensional image from all of the layers, settings, and other information in a composition that make up the model for that image. The rendering of a movie is the frame-by-frame rendering of each of the frames that make up the movie. For more information on how each frame is rendered, see Render order and collapsing transformations.

Though it is common to speak of rendering as if this term only applies to final output, the processes of creating previews to show in the Footage, Layer, and Composition panels are also kinds of rendering. In fact, it is possible to save a RAM preview as a movie and use that as your final output. (See Preview video and audio.)

After a composition is rendered for final output, it is processed by one or more output modules that encode the rendered frames into one or more output files. This process of encoding rendered frames into files for output is one kind of exporting.

Note: Some kinds of exporting don’t involve rendering and are for intermediate stages in a workflow, not for final output. For example, you can export a project as an Adobe Premiere Pro project by choosing File > Export > Adobe Premiere Pro Project. The project information is saved without rendering. In general, data transferred through Dynamic Link is not rendered.

A movie can be made into a single output file (such as a movie in an F4V or FLV container) that contains all of the rendered frames, or it can be made into a sequence of still images (as you would do when creating output for a film recorder).

For a video tutorial on rendering and exporting, go to the Adobe website at www.adobe.com/go/vid0262.

Aharon Rabinowitz provides an introduction to rendering in his “What is Rendering?” video tutorial—part of the Multimedia 101 series on the Creative COW website.

The Render Queue panel

The primary way of rendering and exporting movies from After Effects is through the Render Queue panel. (See Render and export with the Render Queue panel.)

Important: You do not need to render a movie multiple times to export it to multiple formats with the same render settings. You can export multiple versions of the same rendered movie by adding output modules to a render item in the Render Queue panel.

In the Render Queue panel, you can manage several render items at once, each with its own render settings and output module settings. Render settings determine such characteristics as output frame rate, duration, resolution, and layer quality. Output module settings—which are applied after render settings—determine such post-rendering characteristics as output format, compression options, cropping, and whether to embed a link to the project in the output file. You can create templates that contain commonly used render settings and output module settings.

Using the Render Queue panel, you can render the same composition to different formats or with different settings, all with one click of the Render button:

  • You can output to a sequence of still images, such as a Cineon sequence, which you can then transfer to film for cinema projection.

  • You can output using lossless compression (or no compression) to a QuickTime container for transfer to a non-linear editing (NLE) system for video editing.

  • You can output to H.264 or another highly compressed format for playback on mobile devices such as mobile phones or the Apple iPod.

  • You can output to MPEG-2 for playback from DVD.

Note: To transfer the output rendered from After Effects to film or video, you must have the proper hardware for film or video transfer, or have access to a service bureau that can provide transfer services.

The Adobe Media Encoder

After Effects uses an embedded version of the Adobe Media Encoder to encode most movie formats through the Render Queue panel. When you manage render and export operations with the Render Queue panel, the embedded version of the Adobe Media Encoder is called automatically. The Adobe Media Encoder appears only in the form of the export settings dialog boxes with which you specify some encoding and output settings. (See Encoding and compression options for movies.)

Important: The embedded version of the Adobe Media Encoder used to manage export settings within After Effects output modules does not provide all of the features of the full, stand-alone Adobe Media Encoder application. For information about the full, stand-alone Adobe Media Encoder application, see Adobe Media Encoder Help.

The File > Export menu

You use commands in the File > Export menu to render and export SWF files and XFL files for use in Flash Player or Flash Professional, respectively. (See Rendering and exporting for Flash Professional and Flash Player.)

You can also use commands in the File > Export menu to encode movies into some formats (such as raw DV streams) using QuickTime components. However, in general, you should use the Render Queue panel rather than the QuickTime components available through the File > Export menu. (See Rendering and exporting movies using QuickTime components.)

Choosing formats and output settings

After Effects provides various formats and compression options for output. Which format and compression options you choose depends on how your output will be used. For example, if the movie that you render from After Effects is the final product that will be played directly to an audience, then you need to consider the medium from which you’ll play the movie and what limitations you have on file size and data rate. By contrast, if the movie that you create from After Effects is an intermediate product that will be used as input to a video editing system, then you should output without compression to a format compatible with the video editing system. (See Planning your work.)

Aharon Rabinowitz provides an article on the Creative COW website about planning your project and deciding what formats and settings to use for final output.

Keep in mind the fact that you can use different encoding and compression schemes for different phases of your workflow. For example, you may choose to export a few frames as full-resolution still images (for example, TIFF files) when you need approval from a customer about the colors in a shot; whereas you may export the movie using a lossy encoding scheme (for example, H.264) when you need approval for the timing of the animation.