Using the Integrated MPEG Encoder

When QuickTime assets that are not DVD-compliant are imported into a DVD Studio Pro project, they must be made DVD-compliant. DVD Studio Pro uses its integration with Compressor to encode these assets.

This integration with Compressor provides simplified encoding functionality, with the more advanced attributes automatically set.

Note: If you would like to encode the assets using more advanced Compressor functionality or to take advantage of distributed encoding, you can encode the assets directly in Compressor.

For video assets, the integrated MPEG encoder outputs an MPEG-2 video stream with a closed GOP pattern and a fixed GOP size (15 frames for NTSC and 12 frames for PAL). The exported MPEG video stream can be used for multi-angle tracks. The file type is “.m2v.” See Settings in the MPEG-2 SD and MPEG-2 HD Tabs for information on configuring other aspects of the integrated encoder.

If the file to be encoded has audio multiplexed together with the video, the audio is encoded as a PCM audio file and given the same name as the video file, but with an “.aiff” extension.

See Preparing Audio Assets for more information on audio formats.

Transcoding with the Integrated MPEG Encoder

If you import a QuickTime asset whose video standard is different from the project’s current setting, the integrated MPEG encoder automatically transcodes the asset to the project’s video standard while encoding it. For example, if you are working on a PAL project and accidentally import an NTSC QuickTime file, the NTSC file is encoded as a PAL asset and is imported into the project. Similarly, if you import an HD asset into an SD project, the HD asset is automatically transcoded to SD.

You should be aware, though, that the integrated encoder uses the default Compressor Frame Controls settings (which control the quality of frame size and rate conversions), and the results you get may not be suitable for use in a project. Using Compressor directly or any of a variety of third-party products can provide good transcoding results. You may also choose to have a facility that specializes in video standards conversion transcode the video.

Configuring the Integrated MPEG Encoder

DVD Studio Pro Preferences contain the settings that determine how DVD Studio Pro uses the integrated MPEG encoder.

To configure the integrated MPEG encoder
  1. Choose DVD Studio Pro > Preferences.

  2. Click Encoding to open the Encoding pane.

  3. Configure the settings in the Encoding pane. See Encoding Preferences for information about the options in this pane.

  4. Click Apply to enable the settings, then click OK to close the Preferences window.

Encoding Preferences

The Encoding pane of DVD Studio Pro Preferences contains two tabs: MPEG-2 SD and MPEG-2 HD. Each tab has the same settings, with the exception of the higher bit rate settings allowed in the MPEG-2 HD tab.

Figure. Encoding pane of Preferences, showing the MPEG-2 HD settings.

The settings in the MPEG-2 SD tab are automatically applied to all QuickTime video assets added to an SD project (including those with an HD video resolution) and assets with an SD video resolution added to an HD project. The MPEG-2 HD tab’s settings are applied to QuickTime video assets with an HD video resolution added to an HD project. (An exception are H.264 and HDV QuickTime assets, which are already properly encoded.)

Settings in the MPEG-2 SD and MPEG-2 HD Tabs
  • Aspect Ratio: Select the aspect ratio to use.
    • 4:3: This aspect ratio is only available for SD video assets.
    • 16:9: This aspect ratio is supported by both SD and HD video assets. Note that selecting 16:9 does not convert the video to the 16:9 aspect ratio. The file to be encoded must already be in a 16:9 anamorphic format. See What Exactly Is a 16:9 Asset? for more information.
  • Start: Sets the starting timecode of the encoded MPEG stream. This is most often set to match the timecode of the original video, ensuring that any timecode-based lists you have, such as a chapter list, marker positioning file, or subtitle file, match the encoded video.
  • Drop Frame: Select this checkbox to use drop frame timecode for assets using the NTSC frame rate.
  • Bit Rate: Set the bit rate for the One Pass encoding method and the basic bit rate for the One Pass VBR and Two Pass VBR encoding methods. When using one of the VBR encoding methods, you cannot set Bit Rate any higher than 85% of the Max Bit Rate setting. See Choosing a Bit Rate for SD Projects for more information.
  • Max Bit Rate: Set the maximum bit rate that can be used during a One Pass VBR or Two Pass VBR encode. You cannot set the Max Bit Rate setting lower than the Bit Rate setting or 5 Mbps (whichever is higher). Because the VBR methods are most effective when the maximum bit rate is about double the basic bit rate, or at least 1 to 3 Mbps higher than the basic bit rate, the Max Bit Rate setting is forced to be higher than the Bit Rate setting.

    Note: The Max Bit Rate setting does not affect the size of the encoded file—it only sets the upper limit that can be used during the encode.

  • Reset to Factory Defaults: Click this to restore the current tab’s settings to the default settings.
Settings Outside of the Tabs
  • Method: Select when you want the asset to be encoded.

    Note: An advantage of selecting “Background encoding” is that, once the assets are encoded, the encoded versions of them appear in the Simulator and the Viewer when playing a track. This makes it possible to see the video as it will appear on the DVD, and not the QuickTime version. See Is That the QuickTime or MPEG Encoded Version? for more information.

    • Background encoding: The encoding begins as soon as you import the asset. The encoding takes place in the background, allowing you to continue working on your project. A progress bar appears in the Status column of the Assets tab. Once the encoding process finishes, the Status column displays Done. See Default Columns in the Assets Tab for more information.
    • Encode on build: The encoding does not start until you complete your project and build the VIDEO_TS or HVDVD_TS files.

Using the Integrated MPEG Encoder

Depending on the Method setting in Encoding Preferences, video assets can either begin encoding as soon as you add them to your project, or they can wait until you perform a build of the project.

Is That the QuickTime or MPEG Encoded Version?

When you import QuickTime assets and assign them to elements in your project, it can be important to know whether you are seeing the original QuickTime version of the asset or the MPEG encoded version in the Viewer or Simulator. Seeing the MPEG encoded version has the advantage of allowing you to see the video as it will appear when the DVD is played. The disadvantage of seeing the MPEG encoded version is that the video must be encoded first.

The Method setting in the Encoding pane of DVD Studio Pro Preferences controls whether the encoded versions of the assets can be available while you are authoring the project. With “Background encoding” selected, you will be able to see the encoded versions of the assets as soon as they are encoded. With “Encode on build” selected, you will not be able to see the encoded versions until you build the project.

There are some guidelines DVD Studio Pro uses to determine whether to show the original QuickTime version of the asset or the MPEG encoded version:

  • When you view an asset from the Assets tab in the Viewer, you will see the QuickTime version, whether the encoded version is available or not.

  • When you view an asset from the Track Editor, you will see the encoded version (if available). This is also true when you view the track in the Simulator.

  • When you view an asset in the Menu Editor, you will see the QuickTime version, whether or not the encoded version is available. This is also true when you view the menu in the Simulator.

When you import a QuickTime video asset into DVD Studio Pro, the current Encoding Preferences settings are assigned to it. If you change the Encoding Preferences settings after you have imported a QuickTime video asset, those changes are applied only to new assets you import—they are not applied to existing assets.

Verifying and Changing Encoding Settings

If your project contains a mixture of 4:3 and 16:9 assets or has some assets you want to encode differently than others, you must be sure to set the Encoding Preferences settings before you import the assets. You can use the Encoder Settings dialog to verify and change the encoding settings on assets that have been imported.

To change the encoding settings after importing an asset
Do one of the following:
  • Select the asset and choose File > Encoder Settings (or press Command-E).

  • Control-click the asset in the Assets tab, then choose Encoder Settings from the shortcut menu.

The Encoder Settings dialog appears with the same settings found in the Encoding Preferences pane, with HD projects getting an added Resolution setting.

When you have the “Background encoding” method selected and you make any changes in the Encoder Settings dialog, one of two things happens:

  • If you change the bit rate setting: The current file, whether a complete or partially complete file, is left as is and the encoder starts encoding a new file. This allows you to compare the quality of the two bit rates. If you decide to continue the encoding of the partially completed file, you can set the bit rate (and all other settings, if you have made changes) to the value it used, and the encoder will continue encoding it.

    Note: If the encoded files are being written to the project bundle, they are deleted regardless of whether or not you change the bit rate setting.

  • If you do not change the bit rate setting: The original asset is deleted, whether a complete or partially complete file, and a new encoded file is created. For example, if you want to see the difference between one-pass VBR and two-pass VBR encoding and want to keep the files from both encoding sessions, you need to rename or move the completed one-pass VBR encoded file before re-encoding with the two-pass VBR setting.

If you have the “Encode on build” method selected, these changes will apply once you build your project.

Encoding Settings in HD Projects

Because an HD project can use assets with a wide variety of video resolutions, the Encoder Settings dialog contains a Resolution pop-up menu that shows the asset’s resolution. You are also able to change an asset’s video resolution by choosing a setting from the Resolution pop-up menu.

SD resolution assets (720 x 480i and 720 x 576i) in HD projects can use a bit rate up to 15 Mbps. The Bit Rate setting in the Encoder Settings dialog will not go beyond 15 Mbps when an SD resolution is chosen.

Important: Encoding an asset at a resolution other than its native resolution may result in unacceptable artifacts appearing in the video.

How the Encoded Files Are Named

When you import QuickTime video assets into DVD Studio Pro, the integrated MPEG encoder names the encoded files as follows:

  • The first half is the complete original filename, including its extension.

  • The second half has three parts—the video standard (NTSC or PAL), the encoding bit rate (shown as a four-digit number), and the “.m2v” extension.

For example, if you import an asset named “Main Program.mov,” use the NTSC standard and a bit rate of 5.5 Mbps, the MPEG-encoded filename will be “Main Program.mov_NTSC_5500.m2v.”

Audio files created by the embedded AIFF encoder use the original filename with an added “.aiff” extension.