3G Audio Export Options
When you export a movie to 3G format (by choosing File > Export and then choosing
“Movie to 3G”), you access the following options by clicking Options and then clicking
Audio.
 Audio Format: If your source movie has only one audio track and it is already
compressed, you can choose “Pass through” (so that the audio doesn’t get
compressed again).
 Data Rate: As with video, the more kilobits per second, the better the audio quality.
 Channels: Choose between mono (1 channel) or stereo (2 channels).
 Frames per sample: Available only with AMR audio, this option enables exported
audio data to be packed more efficiently.
 Silence detection: Available only with AMR audio, this option detects audio portions
with low signal levels and adjusts the data rate of the output accordingly.
 Output Sample Rate: Available only with AAC audio. It’s best to match the sample
rate to that of the target device.
 Encoding Quality: Available only with AAC audio. By choosing Best, you can get
higher-quality audio but it takes longer to encode.
Chapter 4
Exporting Files with QuickTime Pro
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