4.5

50Compressor User Guide
MP3 settings in Compressor
The built-in MP3 File and MP3 for Audio Podcasting settings in Compressor use the MP3
transcoding format. This format encodes MP3 files, which are often used for digital audio
players. You can also create custom settings that use the MP3 transcoding format.
Note: You can also create custom settings that use the MP3 transcoding format. However,
the built-in MP3 settings (in the Settings pane) analyze your source media and assign
optimal properties to ensure the best possible transcoding results.
The properties of built-in and custom settings that use this transcoding format are located
in the General inspector and Audio inspector (described below).
Setting summary
Displays the setting name and transcoding format used by Compressor, as well as an
estimated output file size. When you add a setting to a job or change the setting’s
properties, this summary is automatically updated.
General properties
• Name: Displays the name of the setting.
• Description: Displays the description of the setting.
• Extension: Displays the extension of the output file (.mp3).
• Allow job segmenting: This checkbox is dimmed because job segmenting is not available
for settings that output only an audio file.
• Default location: Select an item from the pop-up menu to set the default save location
for transcoded files.
Retiming
Sets the processing algorithm used to adjust the frame rate during transcoding. Select one
of the following options:
• Set to percent of source using: Modifies the output clip’s speed by a percentage of the
source clip’s speed. Enter a value in the percentage field or choose a preset value from
the adjacent pop-up menu (with a down arrow).
• Set to: Sets the duration of the clip. Enter a timecode duration in the field or click the
arrows to increase or decrease the time.
• So source frames play at [frame rate] fps: Nondestructively changes the playback
speed of the clip without discarding frames or creating new frames. This property has
no effect unless the “Frame rate” value in the Video inspector is different from the
source file’s frame rate. For example, if you add a 10-second source file with a frame
rate of 24 fps to Compressor, set the “Frame rate” property in the Video inspector to
25 fps, and then select “So source frames play at 25 fps” in the General inspector, the
resulting duration of the transcoded clip (at 25 fps) will be 9 seconds and 15 frames.
For more information, see Retime video and audio using Compressor.
Audio properties
• Channel layout: Use the pop-up menu to set the audio channel layout. See Audio
channel layouts in Compressor.