SpeexEchoState: Acoustic echo canceller

Internal echo canceller state.

Should never be accessed directly.

Definition at line 62 of file speex_echo.h.

Performs echo cancellation a frame (deprecated)

Performs echo cancellation a frame, based on the audio sent to the speaker (no delay is added to playback ni this form)

Parameters:

st	Echo canceller state
rec	signal from the microphone (near end + far end echo)
play	Signal played to the speaker (received from far end)
out	Returns near-end signal with echo removed

Perform echo cancellation using internal playback buffer, which is delayed by two frames to account for the delay introduced by most soundcards (but it could be off!)

Parameters:

st	Echo canceller state
rec	signal from the microphone (near end + far end echo)
out	Returns near-end signal with echo removed

Used like the ioctl function to control the echo canceller parameters.

Parameters:

st	Echo canceller state
request	ioctl-type request (one of the SPEEX_ECHO_* macros)
ptr	Data exchanged to-from function

Returns:

0 if no error, -1 if request in unknown

Let the echo canceller know that a frame was just queued to the soundcard.

Parameters:

st	Echo canceller state
play	Signal played to the speaker (received from far end)

Destroys an echo canceller state.

Parameters:

st	Echo canceller state

Creates a new echo canceller state.

Parameters:

frame_size	Number of samples to process at one time (should correspond to 10-20 ms)
filter_length	Number of samples of echo to cancel (should generally correspond to 100-500 ms)

Returns:

Newly-created echo canceller state

Reset the echo canceller to its original state.

Parameters:

st	Echo canceller state