# API Notes: CoreAudio framework

## Apple documentation

The full API is described in Apple’s documentation, both the C and Objective-C APIs are available (but see the API Notes below).

These bindings are accessed through the `CoreAudio` package (that is, `import CoreAudio`).

## API Notes

Warning

CoreAudio is a fairly low-level framework and has no Python examples, due to the style of the API I’m not yet convinced that the API actually works correctly from Python.

- A number of structures have a custom wrapper and therefore aren’t passed to functions as usual.

  - AudioBuffer

  - AudioBufferList

  - AudioChannelDescription

  - AudioChannelLayout

  - AudioValueTranslation

  In all cases you should explictly pass an instance of these structure to functions, even for pass-by-reference output parameters. This is needed to the low-level structure of these types.

- The APIs to implement CoreAudio plugins are not supported.

- `CalculateLPCMFlags`: all arguments to this function must be provided, there is no default value for the last argument.

- `FillOutASBDForLPCM`: all arguments to this function must be provided, there is no default value for the last argument.