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DC Offset

Audio that is not centered around the zero baseline in the waveform display is said to have a DC offset. DC offsets are typically caused by electrical conflicts between the sound card and input device. The DC Offset function is used to change the baseline of an audio file by adding a constant value to each sample to compensate for offsets.

DC Offset dialog

Estimating DC Offset

You can estimate the DC offset of an audio file by choosing Statistics from the Tools menu.

Average DC offset

DC Offset controls

The following controls are located in the DC Offset dialog.

Automatically detect and remove

Calculates and corrects the DC offset for each channel individually.

Adjust DC offset by

Allows you to specify a DC offset value manually.

•-2,147,483,648 to 2,147,483,647 for 32-bit data

•-8,388,608 to 8,388,607 for 24-bit data

•-32,768 to 32,767 for 16-bit data

•-128 to 127 for 8-bit data

Compute DC offset from first 5 seconds only

Selecting the Compute DC offset from first 5 seconds only check box specifies that only the first five seconds of a file are analyzed when measuring the DC offset. Be aware that five seconds is not sufficient if the beginning of a file has a long fade-in or mute.

PROCESSING AUDIO

CHP. 10