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# Format atom ('frma')

An atom that shows the data format of the stored sound media.

## Topics

### Data fields

[`Size`](/documentation/quicktime-file-format/Format_atom/Size)

An unsigned 32-bit integer holding the size of the format atom.

[`Type`](/documentation/quicktime-file-format/Format_atom/Type)

An unsigned 32-bit field.

[`Data format`](/documentation/quicktime-file-format/Format_atom/Data_format)

A 32-bit integer indicating the format of the stored data.


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