User Guide

ADOBE ENCORE DVD 2.0
User Guide
32
Bitrate Specifies the number of megabits per second you want the encoded file to have. Only appears if you select
CBR as the Bitrate Encoding option.
The following options appear only if you select VBR as the Bitrate Encoding option:
Encoding Passes Specifies the number of times the encoder will analyze the clip before encoding. Enabled for VBR
only.
Target Bitrate Specifies the number of megabits per second you want the encoded file to have. For VBR, the target
provides an average bit rate. (See “To calculate a bit budget” on page 26.)
Maximum Bitrate Used with VBR only. Specifies the maximum number of megabits per second you want the
encoder to allow. The maximum allowable rate is 9.0 Mbps, providing a safety margin.
Minimum Bitrate Used with VBR only. Specifies the minimum number of megabits per second you want the
encoder to allow. The minimum bit rate must be at least 1.5 Mbps.
M frames Specifies the number of B frames between consecutive I and P frames.
N frames Specifies the number of frames between I frames. This value must be a multiple of the M frames value.
Preset options for audio
The Audio tab of the Project Transcode Presets dialog box contains the following options, depending on the codec
chosen:
Audio format Specifies the codec the encoder uses to compress the audio:
Note: NTSC discs must contain either PCM Audio or Dolby
®
Digital; they cannot contain only MPEG audio. This
restriction does not apply to PAL discs.
• Dolby
®
Digital is a high-quality encoding format developed for multi-channel digital sound and the most common
encoder for DVD-video. Adobe Encore DVD encodes Dolby
®
Digital 2.0 (stereo) audio files.
• MainConcept MPEG Audio uses MPEG-1Layer II audio in stereo.
• PCM (Pulse-Code Modulation) Audio is a lossless audio format sampled at 48 kHz in Adobe Encore DVD. Files
of this format tend to be large, occupying more disc space than the other encoder formats.
Bitrate Specifies the output bit rate of the audio. This option is only available for Dolby
®
Digital and MainConcept
MPEG Audio codecs.N
To view a preset’s parameters
1 Choose File > Transcode > Edit Project Transcode Presets.
2 Choose a preset from the Preset menu. Note the preset summary in the summary, and click OK.
Note: The summary displays the estimated file size per second in the lower right corner. If you change a preset’s
parameter that affects file size, such as target bit rate, the estimate updates to reflect your change.
To create a custom preset
1 Choose File > Transcode > Edit Project Transcode Presets.
2 Choose the preset you want to edit from the Presets pop-up menu.
3 If applicable, type a comment in the Comment box.