About mpeg, About data rate – Adobe Premiere Pro CS4 User Manual
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Last updated 11/6/2011
About MPEG
MPEG is the name of a family of digital audio and video standards specified by the ISO/IEC Moving Picture Experts
Group. MPEG standards include several keyframe-based compression methods. It requires significant processing
power and time to generate MPEG files from other video formats.
MPEG-1
Used for the Internet and CD-ROM, providing picture quality comparable with VHS quality at quarter-
screen frame size.
MPEG-2
Delivers higher quality video than MPEG-1. A specific form of MPEG-2 was chosen as the standard for
compressing video for DVD video. This standard is called DVD-compliant MPEG-2. MPEG-2 compression is also
used in HDV, and supported in the Blu-ray Disc and HD-DVD formats.
MPEG-4
Includes many of the features of MPEG-1 and MPEG-2, and adds support for interactivity. It offers better
compression and reduces file size while maintaining the same perceptual quality level as MPEG-2. MPEG-4 part 10
(H.264, AVC) is used by the Blu-ray Disc and HD-DVD formats. For more information about MPEG-4, see “Overview
of the MPEG-4 standard” at
The Adobe Media Encoder offers some MPEG presets to optimize the output quality for various project types. If you’re
experienced with MPEG encoding, you can further fine-tune projects for specific playback situations by customizing
the presets in the Export Settings dialog box.
In After Effects, you can create MPEG-2 and MPEG-2 DVD video. In Adobe Premiere Pro, you can create various
types of MPEG video by using the File
> Export > Media command. Also, in Adobe Premiere Pro you can export
directly to DVD-compliant video by using the File
> Adobe Dynamic Link > Send To Encore command. Any video
you send to Encore is automatically transcoded to MPEG-2 if it isn’t already in that format.
After Effects and Adobe Premiere Pro add metadata to MPEG-2 files that Encore can read for aid in authoring and
building DVDs. This metadata enables Encore to multiplex audio and video, automatically generate DVD chapter
points, and open clips in the applications from which they were rendered. For more information, see Encore Help.
More Help topics
About data rate
With some video and audio codecs, you can specify the data rate, also called the bit rate, which controls the amount
of information that must be processed each second during playback. Specifying a data rate actually sets the maximum
data rate, because the actual data rate varies depending on the visual content of each frame.
To maximize the quality of encoded video, set the data rate as high as the target medium can support while keeping
the file size within the capacity of the target medium. If you plan to stream video to an audience using dial-up Internet
access, this may be as low as 20 Kbps; however, if you plan to distribute video on DVD, it may be as high as 9.8 Mbps.
Data rate guidelines for some media follow:
DVD production
The maximum data rate for both video and audio played in DVD-compliant MPEG-2 format is 9.8 Mbps.
Blu-ray Disc production
The maximum data rate for both video and audio played in Blu-ray Disc format is 48 Mbps.
Hard disk playback
If the final video will be played back from hard disks, determine the typical data transfer rate of
your audience’s hard disks and set the data rate accordingly. If you’re exporting video for use in another editing system
or to be imported into a compositing application, you’ll want to export at the maximum quality. Use a lossless codec
or the codec supported by your video capture card, and specify the data rate that the editing system supports for video
capture and editing.