Index: speex/include/speex/speex_echo.h |
=================================================================== |
--- speex/include/speex/speex_echo.h (revision 0) |
+++ speex/include/speex/speex_echo.h (revision 0) |
@@ -0,0 +1,170 @@ |
+/* Copyright (C) Jean-Marc Valin */ |
+/** |
+ @file speex_echo.h |
+ @brief Echo cancellation |
+*/ |
+/* |
+ Redistribution and use in source and binary forms, with or without |
+ modification, are permitted provided that the following conditions are |
+ met: |
+ |
+ 1. Redistributions of source code must retain the above copyright notice, |
+ this list of conditions and the following disclaimer. |
+ |
+ 2. Redistributions in binary form must reproduce the above copyright |
+ notice, this list of conditions and the following disclaimer in the |
+ documentation and/or other materials provided with the distribution. |
+ |
+ 3. The name of the author may not be used to endorse or promote products |
+ derived from this software without specific prior written permission. |
+ |
+ THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
+ IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
+ OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
+ DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, |
+ INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
+ (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
+ HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
+ STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN |
+ ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
+ POSSIBILITY OF SUCH DAMAGE. |
+*/ |
+ |
+#ifndef SPEEX_ECHO_H |
+#define SPEEX_ECHO_H |
+/** @defgroup SpeexEchoState SpeexEchoState: Acoustic echo canceller |
+ * This is the acoustic echo canceller module. |
+ * @{ |
+ */ |
+#include "speex/speex_types.h" |
+ |
+#ifdef __cplusplus |
+extern "C" { |
+#endif |
+ |
+/** Obtain frame size used by the AEC */ |
+#define SPEEX_ECHO_GET_FRAME_SIZE 3 |
+ |
+/** Set sampling rate */ |
+#define SPEEX_ECHO_SET_SAMPLING_RATE 24 |
+/** Get sampling rate */ |
+#define SPEEX_ECHO_GET_SAMPLING_RATE 25 |
+ |
+/* Can't set window sizes */ |
+/** Get size of impulse response (int32) */ |
+#define SPEEX_ECHO_GET_IMPULSE_RESPONSE_SIZE 27 |
+ |
+/* Can't set window content */ |
+/** Get impulse response (int32[]) */ |
+#define SPEEX_ECHO_GET_IMPULSE_RESPONSE 29 |
+ |
+/** Internal echo canceller state. Should never be accessed directly. */ |
+struct SpeexEchoState_; |
+ |
+/** @class SpeexEchoState |
+ * This holds the state of the echo canceller. You need one per channel. |
+*/ |
+ |
+/** Internal echo canceller state. Should never be accessed directly. */ |
+typedef struct SpeexEchoState_ SpeexEchoState; |
+ |
+/** Creates a new echo canceller state |
+ * @param frame_size Number of samples to process at one time (should correspond to 10-20 ms) |
+ * @param filter_length Number of samples of echo to cancel (should generally correspond to 100-500 ms) |
+ * @return Newly-created echo canceller state |
+ */ |
+SpeexEchoState *speex_echo_state_init(int frame_size, int filter_length); |
+ |
+/** Creates a new multi-channel echo canceller state |
+ * @param frame_size Number of samples to process at one time (should correspond to 10-20 ms) |
+ * @param filter_length Number of samples of echo to cancel (should generally correspond to 100-500 ms) |
+ * @param nb_mic Number of microphone channels |
+ * @param nb_speakers Number of speaker channels |
+ * @return Newly-created echo canceller state |
+ */ |
+SpeexEchoState *speex_echo_state_init_mc(int frame_size, int filter_length, int nb_mic, int nb_speakers); |
+ |
+/** Destroys an echo canceller state |
+ * @param st Echo canceller state |
+*/ |
+void speex_echo_state_destroy(SpeexEchoState *st); |
+ |
+/** Performs echo cancellation a frame, based on the audio sent to the speaker (no delay is added |
+ * to playback in this form) |
+ * |
+ * @param st Echo canceller state |
+ * @param rec Signal from the microphone (near end + far end echo) |
+ * @param play Signal played to the speaker (received from far end) |
+ * @param out Returns near-end signal with echo removed |
+ */ |
+void speex_echo_cancellation(SpeexEchoState *st, const spx_int16_t *rec, const spx_int16_t *play, spx_int16_t *out); |
+ |
+/** Performs echo cancellation a frame (deprecated) */ |
+void speex_echo_cancel(SpeexEchoState *st, const spx_int16_t *rec, const spx_int16_t *play, spx_int16_t *out, spx_int32_t *Yout); |
+ |
+/** 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!) |
+ * @param st Echo canceller state |
+ * @param rec Signal from the microphone (near end + far end echo) |
+ * @param out Returns near-end signal with echo removed |
+*/ |
+void speex_echo_capture(SpeexEchoState *st, const spx_int16_t *rec, spx_int16_t *out); |
+ |
+/** Let the echo canceller know that a frame was just queued to the soundcard |
+ * @param st Echo canceller state |
+ * @param play Signal played to the speaker (received from far end) |
+*/ |
+void speex_echo_playback(SpeexEchoState *st, const spx_int16_t *play); |
+ |
+/** Reset the echo canceller to its original state |
+ * @param st Echo canceller state |
+ */ |
+void speex_echo_state_reset(SpeexEchoState *st); |
+ |
+/** Used like the ioctl function to control the echo canceller parameters |
+ * |
+ * @param st Echo canceller state |
+ * @param request ioctl-type request (one of the SPEEX_ECHO_* macros) |
+ * @param ptr Data exchanged to-from function |
+ * @return 0 if no error, -1 if request in unknown |
+ */ |
+int speex_echo_ctl(SpeexEchoState *st, int request, void *ptr); |
+ |
+ |
+ |
+struct SpeexDecorrState_; |
+ |
+typedef struct SpeexDecorrState_ SpeexDecorrState; |
+ |
+ |
+/** Create a state for the channel decorrelation algorithm |
+ This is useful for multi-channel echo cancellation only |
+ * @param rate Sampling rate |
+ * @param channels Number of channels (it's a bit pointless if you don't have at least 2) |
+ * @param frame_size Size of the frame to process at ones (counting samples *per* channel) |
+*/ |
+SpeexDecorrState *speex_decorrelate_new(int rate, int channels, int frame_size); |
+ |
+/** Remove correlation between the channels by modifying the phase and possibly |
+ adding noise in a way that is not (or little) perceptible. |
+ * @param st Decorrelator state |
+ * @param in Input audio in interleaved format |
+ * @param out Result of the decorrelation (out *may* alias in) |
+ * @param strength How much alteration of the audio to apply from 0 to 100. |
+*/ |
+void speex_decorrelate(SpeexDecorrState *st, const spx_int16_t *in, spx_int16_t *out, int strength); |
+ |
+/** Destroy a Decorrelation state |
+ * @param st State to destroy |
+*/ |
+void speex_decorrelate_destroy(SpeexDecorrState *st); |
+ |
+ |
+#ifdef __cplusplus |
+} |
+#endif |
+ |
+ |
+/** @}*/ |
+#endif |
Property changes on: speex/include/speex/speex_echo.h |
___________________________________________________________________ |
Name: svn:executable |
+ * |